Agreed. 3000W, intermittent use, 1000W continuously. I'm a sparky, and use mine continuously with an 850W SDS for chopping out. Never had to reset the thermal cut out, and it's 15 yrs old. And don't forget stuff like power factor. 3000W kVA with a 0.9 power factor is actually 2700W intermittent (kVAr). kVAr is the true maximum power output.
Most people using them won't have the slightest idea about power factor. Like useing 240v extension leads upto to job then the transformer. I seen a steel RSJ dropped onto an extension lead and the lucky escape a man had. 110v extensions the way to go.
@@g7mks383 Which is why anything that's 240V that's being used outdoors should be protected by a 30mA RCD . (It takes approx 60mA at 240V to stop a human heart, which is why RCDs are rated at half that.) You're asking for trouble if you dont . If you have long runs of 110V extension leads then things like voltage drop come into play and whatever tool you're using won't perform as well. Or better still use cordless whenever you can, and remove the trip hazard of trailing leads, as well as risk of electric shock. ;)
kVAr refers to the _reactive_ power consumption of the device, not its 'true maximum power output'. The point you are making - I think - is that a device with an operating power factor of 0.9 will have an effective real power rating (that is, 'useful' power expressed in W or kW) that is less than its apparent power rating in VA or kVA.
You are right that they are an interesting thing... A lot of thought went into these devices, specifically with safety in mind. The secondary winding is center tapped to earth with the L & N output floating & completely isolated from the primary. This means that the maximum shock you can get is 55V to earth ie: not lethal. The reason they overheat so easily is because the transformer windings are epoxy encapsulated for wet use safety. The bin is also waterproof. This makes them safe to use in the rain or wet conditions.
The major problem here is is the installation is TN-C-S (also known as PME) when a Neutral fault will make YOU the fault current conductor or on a TT service you could become both conductors which will definitely give your hair a good Perm
@@Mike_5 I'm sure there are quite a few instances where 110V CTE isolating transformers are used on small sites with TN-C-S supplies (individual house restorations for example) but most of the time they will be used on construction sites where the DNO supply will not provide an earth connection, so it will be TT. I can't see how the use of a 110V transformer presents an increased hazard in the case of an open-circuit neutral/earth conductor or local earth-electrode connection.
@@amd4life89 Yes people seem to ignore the line to line voltage as if you can only get a line to earth shock. Although admittedly line-earth shocks are more common.
Hi Roger as a retired electrical contractor , I was always fascinated by how many contractors were carrying around heavy transformers that were way bigger than they needed . And of course the big units always have a tendency to trip RCDs because of the inrush they produce . Obviously your large concrete splitter needs a beefy transformer , but I can guarantee many only need a smaller unit so saving their backs lugging them around . Best wishes and kind as always .
Most contractors nowadays use cordless power tools, much better idea. No heavy transformer to be lugging around the place also, transformers are only useful if you've got power in the building you're working on, in the first place. You'd also need extension leads which have a tendency to get tangled up representing a trip hazard, not to mention a Generator in the van just in case theres no power on site. cordless tools a much better idea charged up overnight in a charging station, fully comply with safety regs and can be used anywhere.
@@davidodonovan4982 hi David we would still use them for for things like using large core bits that would tend to totally drain a battery SDS drill . And to be honest a good quality 110v SDS drill will last you years unlike battery gear . Best wishes and kind regards 😀👍
@Graham Allen Ah, another Brit basher. You obviously employ the wrong builders. I've been in the trade for 40 years on all kinds of projects and the vast majority I've worked with work very hard.
@@charlieb6001 it's a quip just like the British rail stale buttie and wrong type of snow......I worked as a driver on rails for 34 years I don't get up set at quips ....goes with territory
Good info there Roger that I never knew, as I don't think I ever got instructions with it. My reset button has been stuck in for years now and the tranny still working, but I don't have it continously on at full load.
Hi I'm Roger Busy Bee from the Skill Builder Channel and my favourite Transformer is Soundwave because he could transform into a Cassette Player and play all my favourite Celine Dion songs.
Sickening to hear about the loss if your transformer, the sick part having to be around grunts luke thar, never mind working near them. I'd have stuck a tracking tile/gps tracker etc to any bulky equipment I was using onsite. Had you done so, all you had to do was use the app on your phone to find out what van it's in and record reg no, go back in and ask 'have you seen my xyz?" Bring your phone out, "Ah, it's okay I see it's nearby." Mention bringing in the law, go out for few mins, guaranteed it will have miraculously reappeared.
Always tickled me when you see a 230v mains lead dragged all over the place and then a 110v transformer on the end of it, kind of defeats the object of having safe equipment on site, seen it so many times in the past.
I always go with continuous rating on the transformer. Which is usually half the kva rating. So total Watts on on tools add up to the continuous rating not the peak rating
My neighbour Jason works mainly in Central London and ditched the 110V Transformer & Associated Tools a couple of years ago, as he was having to go through the rigmarole of Pat Testing every Monday morning. 😨 He's on Milwaukee's 18V platform now 👍 On one job he did he even had to fill in a form quoting the Vibration Characteristics of each tool he'd be using and the length of time he'd be using theml 😨🙃
Yes it has become a bit crazy now. People don't want to end up with a claim against them but those forms are works of fiction we just put down anything to get out of that office and on with the job.
@@SkillBuilder H&S is a financially rewarding and self-perpetuating industry. I think there is a group of pen pushers somewhere who sit around a table all day dreaming what they can come up with next. In 40 years as a tradesman not once have I been asked, nor has anybody I've ever known, my opinion on H&S matters. The one key thing these pen pushers miss is that when you work on a building site you develop a sixth sense in safety awareness; they treat us like imbeciles who have never set foot on a site before. Building sites are inherently hazardous and we are fully aware of the dangers; filling in forms does not make sites any less hazardless but it I suppose it gives someone a job and a feeling of power and makes someone else rich.
Lots of people think an RCD will give you equivalent protection - I'm not sure that's the case, the point is these isolate you from the electrical installation, if you don't have that isolation then I believe you're subject to getting injured from earth faults that might develop on a building site.
They have an earth reference at the center of the 110v wind anyway, so anyone who can complete a circuit still gets a 55v belt, not fully isolating. RCDs must be used on 230v equipment.
An RCD won't provide any protection on the secondary side of a transformer. However, if you place an RCD into the 230 volt lead feeding the primary side, AND that RCD is placed at the start of that lead, that is you plug that lead into the RCD, then it will provide electric shock protection for that primary side cable. A fault occuring on the secondary side will not be protected by that RCD.
Get a plug in remote control switch. You have a little remote in you pocket and you can switch it off from 10 metres away. £10 on Amazon. Just got one when my power take of vacuum packed up and Henry had to come off the bench.
Thanks you are correct in they are for intermittent use you can always stand the transformer on a couple of bricks. The most important thing that every person does is use them incorrectly. There purpose is to protect you from electric shock which can kill you. 110 volts is safer, so why run 240 volt lethal extension leads around a site to then plug in an 110 volt transformer. Those extension leads are siting waiting to get chopped or slashed and kill you or your work mate. Plug the transformer in at a safe location then use 110 volt extension leads. The inset photo shows the danger lurking. As they say a little knowledge is dangerous. Its the just get the job done attitude that will catch you out, and you won't be going to the home you want just the funeral home.
Gee, that’s a really good idea.., And you can stick your finger in the water to see if it’s getting warm. Just make sure you have no footwear on, to make sure you’re really ‘grounded’ ! Oh ! Just video all this; so we can make sure you’re getting electro.. ops, everything right !
Not cheap. I used a generator for most of my work, only used a tranny to fitting kitchens. Some great tips below so be nice to your unit. It's mostly battery if you've got 2 spare as a lot of sites expect you to supply your own power. General use 240v converters on site in various places helps. Cannot remember the last time I bought one mind...
had many 3kw transformers most overheat and burn out take off lid only 4 screws to allow heat to escape or buy a 4kw had the same one for over 10 years and its on all day as well it gets hot nut it gives me no problems
Really interesting. 99% of people must abuse these then. I never knew they were for intermittent use but makes complete sense. All the heaters I have seen plugged into these and left running for hours……
If the thermal cut out is not opening then all is good. The ''continuous duty'' is lower than their intermittent duty rating, but it is a true continuous duty.
I'm transformed 😂😂😂 Didn't know about the intermittent use bit I'll be honest. What did annoy me in my 'days of on the tools' is the MCB nearly always kicked out on the consumer unit when you plug it in, especially in the winter when the tranny is cold. The customer thinks your plugging something dodgy in when you ask if they could pop in and reset it. 😊
Only time I've known the thermal cutout operate was when we damaged a lead driving an access tower over it. The lead was sparking 😂 and most tools are nowhere near the max load of these trannys so can run continuously. 3kva is a lot! That's why they make the little 1.5kva (I think) units for single tools. I hired a cement mixer recently. Got a 5kva tranny with it (all the hire shop had) and ran it all day, mixed up 1.2m³ continuously. Mixer was about 600w.
I recently bought a 0.5 kVA continuous / 0.75 kVA ''tool rating'' (i.e intermittent) second hand for £25. Much lighter than my 1.5 kVA/2.25 kVA I had previously, and I doubt it will ever trip in a life time with normal power tool usage, even flat out, even with 2 people if I had to guess. Unless you had a scenario were a prolonged high load like a mixer or such is used, I doubt it will ever trip. And I can always bring out the larger one for those few occasions. If I was a tradesman I would go cordless, but for DIY I can have a corded version of everything I need sitting on the shelf ready to go, without batteries deteriorating and eventually dying from lack of regular use.
I'm using one that's double the physical size, and also weighs nearly 3 times as much, to power my chop saw. Those little 16Amp transformers just don't have the power, and the chop saw hardly scratches the metal it's cutting. But using a 32Amp transformer, I can cut through quite a bit more, and unless the light fingered out there have a wheel barrow, it's not something your going to run off with.
mines absolutely hammered... and a while ago i turned it on and the thermal switch went bang so it hasnt got a thermal switch now. ideally id move away and go cordless but then id need a new mitre saw as my kapex is 110v.... my track saw, extractors, routers etc are all 110v so thats a canny bill to replace all of that lot
Probably should of explained the purpose of a on site isolating transformer which I understand to be that you never get more than 55v between a conductor and true earth.
Personally I would never go with a unit less than 10 kVA. The whole safety goal is defeated if the transformer melts down and the secondary comes into contact with the high voltage primary. What would you rather electrocution or a little bit of grunt moving a transformer? A small hand truck and it's never been an issue in all my years. On projects with 2 people running tools simultaneously I bring 2 of these. And the inrush current thing is overblown, a very simple fix with a soft starter that momentarily puts a lamp in series with the input power and is bridged a second later with a timed switch. The initial magnetisation current is limited by the resistance of the bulb and gets the flux swinging in the core, and then the bulb is bypassed and taken out of circuit afterwards.
In a world of RCD's and RCBO's it does beg the question, why are we still bothering with 110v? No other country in Europe uses 110v and they don't seem to have any major safety issues. More and more on site 110v is being replaced with 18v. Isn't it about time this system is due for a review and the construction industry looks at protection at source being law.
Because if an RCD with 240 volts (and I do mean 240 not 230 ) doesn't trip for whatever reason, then you're dead. If you're using 110 volt appliances and you come into contact with that voltage, you don't die.
I think you'll find if you derate the transformer by the duty cycle then you can use it continuously. For example if the duty cycle is 30% and the transformer is rated for 1,000 VA then you should be OK with a load of 300 VA using it continuously. The cause of these issues is the transformer is made to be waterproof and to withstand the abuse of being on a building site. Put the same transformer in a metal box with louvres for ventilation and it'd probably run happily all day at rated load. The other approach would be to buy a transformer that's got a higher power rating than you need. Of course that's going to cost more and be heavier.
It's kinda linear. half load twice the time. It's not a welder, so they should all be rated 100% duty, but now every thing is cheaped out on. All trannys VA was rated full load, heat soaked forever run mode. Now it's have a guess, we didn't certify it, we just make it and deliver it to anyone on alibaba
@@SkillBuilder exactly, and I think it's also the point is not to have 5 guys working off one of these trannys with splitter boxes. One chippy using a skill saw and chop saw back and forth is fine as he using one tool at a time and not continuous
@@UberAlphaSirus I understand where you're coming from however remember this is a portable device. Weight is a factor as is cost. I just took delivery of a 20VA isolation transformer from,Ali. Price was right and 20VA is overkill for my needs. I'll check it with an insulation tester before I trust my life to it but it looks the goods with plenty of insulation between the windings. Transformers and motors seem pretty simple devices until they're not. The difference between 50Hz and 60Hz generally doesn't matter until you've got thousands of slurpy makers running on 110V at 50Hz via a transformer and the motors are not lasting all that long.
Please dont exceed its rated KWH rating, try to use one at least twice the watts of the tool being used. I have a 5KWH one for all day use and a light 1.5 one for the odd job.
There is no KWH rating for a transformer. You are getting your units mixed up. There is KVA, KW and KWH. They are not interchangeable. The only ones that apply to transformers in this set are KVA and KW.
With modern electrics and RCD extension leads will they eventually become a thing of the past and just have the 240v tools. I've been working in domestic land for a few years now and have switched over.... Probably going to get a bunch of flack for that but the vac runs the chop saw better and the rail saw. 110 only gives 800w from the vac. Or will it go just to heavy ass 40v Makita. Heavy though.
@@SkillBuilder Because cold ground or concrete will work even better to get the heat out. I do remember an old german transformer that had optional feet that you can pop out.
I've watched loads of Transformers films. I never knew Optimus Prime worked on 110v and could only do intermittent use. When the Autobot Transformers are battling the Decepticons, they do 5 mins on and 15 mins off duty-cycles?
Should I buy a 110v mitre saw and buy a transformer to use for domestic or buy a 240v mitre saw and use a transformer and convert it to 110v for site use. I want to use it for site use and domestic use so what’s better? 110v or 240v
They are for continuous use at a lower load. That one you have the is rated for 3000w short term and 1500w long term. I use them on site to power festoon lighting and there on all day every day for weeks
As a site electrician working on huge high rise building sites in Sydney, I find this transformer idea a bit of a nuisance. I'm glad we don't mandate this madness here. We use 240v rated tools and are glad to do so. We do however require all electrical tools to be inspected monthly for damage.
my wallpaper stripper is 110v cannot really use it intermittently when stripping a house. and yes the transformer gets super hot and did trip the other day. seems like it was a daft idea to make a 110v wallpaper stripper (it also has a big water tank)
How far does the 110v rule apply though every site is different, some sites say your cordless tools must be charged on a 110v charger so you still need a transformer others will have a container with loads of 240v sockets in ? It's hit and miss.
the ones that say you must charge batteries via 110v don't work for them, they're called nonce sites and the site manager is the biggest nonce of them all.
Maybe I have just been luck my transformer is plugged in all day and gets used for way longer than 5mins and I have never had to use the thermal switch.
I always thought that if you had to use with extension leads you had to have the transformer plugged directly into the socket, and then use 110v extension leads, not plug the transformer into a 240 extension lead like in your clip of the breaker as the drop in resistance along the 240 extension lead damages the transformer.
No, electrically, there is no problem at all plugging the transformer into the extension lead. There is less current being drawn on the 240V side, so the voltage drop is likely to be less, do make sure that you have fully uncoiled the 240V lead though. On the 110V side the current will effectively be doubled, so you need a heftier extension lead, especially if running long distances. On some building sites however, there will be a policy of plugging the transformer into the socket and running the extensions in 110V. This is because the transformer is wired so that there is only 55V to earth on the 110V side, so if the extension lead gets damaged, the danger is much less to the workers, than if a 240V extension lead is damaged, that would have the full 240V to earth.
5KVA transformers are better plus all CE Rated transformers come with a thermal protection device fitted. 5KVA are no good in most domestic settings as they’ll normally trip the B Type MCB when switched on due to inrush current but, should be fine in commercial/industrial locations. There’s no legal requirement to run 110V on sites however, most larger scale sites do require it & should provide industrial/vented transformers as part of their onsite installations for contractor use if they specify it’s requirement. Cordless doesn’t yet have the longevity for disc cutters/breakers & prohibition of combustion engines indoors should rule out that option for most so, transformers will still be with us for a while at least. Not much else that a battery doesn’t run on site these days. Might be worth people following your lead & adopting cordless solutions.
Same thing happened to me with a laser level. It was screwed to the wall in a customer's house. There was only me and one other builder. When I went back the following day The laser level was gone and he said exactly the same thing laser level. What laser level? I've not seen a laser level.
You can never rule out the customer stealing it. That has happened to me. I did some work in a drug rehab unit and everything in my tool box was a potential fix.
@@SkillBuilder Worked in one of the busiest Garda stations in Ireland as an apprentice Carpenter. First day we arrived the guy who looked after the facilities told us not to leave any tools down these are the biggest thieves going.
110v is only really used in industrial settings and building sites. You won't find it on houses like the states 120v. It's also centre tapped to keep touch voltages low so it 55v - 0v - 55v.
My guess is that someone looked at current loads and decided that having a higher voltage meant they can get away with less current. Lower current means smaller wires and copper was not in great supply at the time people were looking at it. The us also has 240 for some things like dryers and car chargers but it’s done with a split phase so 2x 120 combined I believe. We tend to use 3 phase when we have big power loads and generally that tends to be in industrial setting and so we end up with smaller copper again.
Why don't Brits develope power tools that do not require transformers? Rented one to power a German made roto hammer with an American (110) plug while building an extension in Scotland year 2000. Very inconvenient.
We require 110 volt tools, for safety reasons. Now tell me how you are going to get 110 volts from our 230 volt electrical system without using a transformer? I would love to hear your answer.
It's not often you would be drawing 3kw of it for any prolonged period so you shouldnt have to keep unplugging it really under normal use. I mean really, who does that?
But the appliance requires 110 volts which is why it is referred to as a 110 volt transformer. It would be pretty crap if we have 110 volt appliances being fed from a 55 volt transformer. Think of the confusion and mistakes that will occur. And you can get a 110 volt shock if you contact across both live terminals/wires on the secondary. Though that is less likely to occur than a line to human/earth situation.
To reduce equipment losses engrave your tools: 'STOLEN from Roger Bisby' - and use a permanent marker pin to fill the engraving. It will reduce thefts but may end up with everybody marking their tools with your name - can't win!!
Agreed. 3000W, intermittent use, 1000W continuously. I'm a sparky, and use mine continuously with an 850W SDS for chopping out. Never had to reset the thermal cut out, and it's 15 yrs old. And don't forget stuff like power factor. 3000W kVA with a 0.9 power factor is actually 2700W intermittent (kVAr). kVAr is the true maximum power output.
Most people using them won't have the slightest idea about power factor. Like useing 240v extension leads upto to job then the transformer. I seen a steel RSJ dropped onto an extension lead and the lucky escape a man had. 110v extensions the way to go.
@@g7mks383 Which is why anything that's 240V that's being used outdoors should be protected by a 30mA RCD . (It takes approx 60mA at 240V to stop a human heart, which is why RCDs are rated at half that.) You're asking for trouble if you dont . If you have long runs of 110V extension leads then things like voltage drop come into play and whatever tool you're using won't perform as well. Or better still use cordless whenever you can, and remove the trip hazard of trailing leads, as well as risk of electric shock. ;)
kVAr refers to the _reactive_ power consumption of the device, not its 'true maximum power output'. The point you are making - I think - is that a device with an operating power factor of 0.9 will have an effective real power rating (that is, 'useful' power expressed in W or kW) that is less than its apparent power rating in VA or kVA.
@@g7mks383 … nor any clue about spelling!
Sparky eh? 😂😂😂 (KVAr is not the maximum power output … that would be kW, the real power output)
You are right that they are an interesting thing... A lot of thought went into these devices, specifically with safety in mind. The secondary winding is center tapped to earth with the L & N output floating & completely isolated from the primary. This means that the maximum shock you can get is 55V to earth ie: not lethal. The reason they overheat so easily is because the transformer windings are epoxy encapsulated for wet use safety. The bin is also waterproof. This makes them safe to use in the rain or wet conditions.
The major problem here is is the installation is TN-C-S (also known as PME) when a Neutral fault will make YOU the fault current conductor or on a TT service you could become both conductors which will definitely give your hair a good Perm
@@Mike_5 I'm sure there are quite a few instances where 110V CTE isolating transformers are used on small sites with TN-C-S supplies (individual house restorations for example) but most of the time they will be used on construction sites where the DNO supply will not provide an earth connection, so it will be TT. I can't see how the use of a 110V transformer presents an increased hazard in the case of an open-circuit neutral/earth conductor or local earth-electrode connection.
I'm being a bit pedantic here but your wording isn't quite right....The maximum shock you can get is 110V, the maximum shock to earth is 55V ;)
@@amd4life89 Yes people seem to ignore the line to line voltage as if you can only get a line to earth shock. Although admittedly line-earth shocks are more common.
Hi Roger as a retired electrical contractor , I was always fascinated by how many contractors were carrying around heavy transformers that were way bigger than they needed . And of course the big units always have a tendency to trip RCDs because of the inrush they produce . Obviously your large concrete splitter needs a beefy transformer , but I can guarantee many only need a smaller unit so saving their backs lugging them around . Best wishes and kind as always .
Most contractors nowadays use cordless power tools, much better idea.
No heavy transformer to be lugging around the place also, transformers are only useful if you've got power in the building you're working on, in the first place. You'd also need extension leads which have a tendency to get tangled up representing a trip hazard, not to mention a Generator in the van just in case theres no power on site. cordless tools a much better idea charged up overnight in a charging station, fully comply with safety regs and can be used anywhere.
@@davidodonovan4982 hi David we would still use them for for things like using large core bits that would tend to totally drain a battery SDS drill . And to be honest a good quality 110v SDS drill will last you years unlike battery gear . Best wishes and kind regards 😀👍
Well the transformers match the builders I contract ....as thay only work intermittently 5mins work 15mins nattering! So 110v tranny spot on for use
😂
Any jobs going 😂
@Graham Allen Ah, another Brit basher. You obviously employ the wrong builders. I've been in the trade for 40 years on all kinds of projects and the vast majority I've worked with work very hard.
@@charlieb6001 Lol, comedy gold.
@@charlieb6001 it's a quip just like the British rail stale buttie and wrong type of snow......I worked as a driver on rails for 34 years I don't get up set at quips ....goes with territory
Good info there Roger that I never knew, as I don't think I ever got instructions with it. My reset button has been stuck in for years now and the tranny still working, but I don't have it continously on at full load.
Hi I'm Roger Busy Bee from the Skill Builder Channel and my favourite Transformer is Soundwave because he could transform into a Cassette Player and play all my favourite Celine Dion songs.
Celine Dion? Wash your mouth out with soap.
Sickening to hear about the loss if your transformer, the sick part having to be around grunts luke thar, never mind working near them. I'd have stuck a tracking tile/gps tracker etc to any bulky equipment I was using onsite.
Had you done so, all you had to do was use the app on your phone to find out what van it's in and record reg no, go back in and ask 'have you seen my xyz?"
Bring your phone out,
"Ah, it's okay I see it's nearby."
Mention bringing in the law, go out for few mins, guaranteed it will have miraculously reappeared.
The bit about hating em was spot on there a pain lugging from job to job
Always tickled me when you see a 230v mains lead dragged all over the place and then a 110v transformer on the end of it, kind of defeats the object of having safe equipment on site, seen it so many times in the past.
As with most safety rules, in practice it is just a formality and only enforced to the extent required to cover ones ass!
I always go with continuous rating on the transformer. Which is usually half the kva rating. So total Watts on on tools add up to the continuous rating not the peak rating
No you don't
My neighbour Jason works mainly in Central London and ditched the 110V Transformer & Associated Tools a couple of years ago, as he was having to go through the rigmarole of Pat Testing every Monday morning. 😨 He's on Milwaukee's 18V platform now 👍 On one job he did he even had to fill in a form quoting the Vibration Characteristics of each tool he'd be using and the length of time he'd be using theml 😨🙃
Yes it has become a bit crazy now. People don't want to end up with a claim against them but those forms are works of fiction we just put down anything to get out of that office and on with the job.
@@SkillBuilder H&S is a financially rewarding and self-perpetuating industry. I think there is a group of pen pushers somewhere who sit around a table all day dreaming what they can come up with next. In 40 years as a tradesman not once have I been asked, nor has anybody I've ever known, my opinion on H&S matters. The one key thing these pen pushers miss is that when you work on a building site you develop a sixth sense in safety awareness; they treat us like imbeciles who have never set foot on a site before. Building sites are inherently hazardous and we are fully aware of the dangers; filling in forms does not make sites any less hazardless but it I suppose it gives someone a job and a feeling of power and makes someone else rich.
Lots of people think an RCD will give you equivalent protection - I'm not sure that's the case, the point is these isolate you from the electrical installation, if you don't have that isolation then I believe you're subject to getting injured from earth faults that might develop on a building site.
They have an earth reference at the center of the 110v wind anyway, so anyone who can complete a circuit still gets a 55v belt, not fully isolating. RCDs must be used on 230v equipment.
An RCD won't provide any protection on the secondary side of a transformer.
However, if you place an RCD into the 230 volt lead feeding the primary side, AND that RCD is placed at the start of that lead, that is you plug that lead into the RCD, then it will provide electric shock protection for that primary side cable.
A fault occuring on the secondary side will not be protected by that RCD.
Cheers Roger, I will check mine, normally cut a load of blocks in one go 👍
Get a plug in remote control switch. You have a little remote in you pocket and you can switch it off from 10 metres away.
£10 on Amazon.
Just got one when my power take of vacuum packed up and Henry had to come off the bench.
Thanks you are correct in they are for intermittent use you can always stand the transformer on a couple of bricks. The most important thing that every person does is use them incorrectly. There purpose is to protect you from electric shock which can kill you. 110 volts is safer, so why run 240 volt lethal extension leads around a site to then plug in an 110 volt transformer. Those extension leads are siting waiting to get chopped or slashed and kill you or your work mate. Plug the transformer in at a safe location then use 110 volt extension leads. The inset photo shows the danger lurking. As they say a little knowledge is dangerous. Its the just get the job done attitude that will catch you out, and you won't be going to the home you want just the funeral home.
well i did not know that! thanks for passing on that little nugget.
Hi, always worked my trany hard, stood in a bucket of water . by 10 am just right to make the tea . Energy saved and recycled .
I dont use mine much but didnt know this so thanks!
⚡ 😉 Stick it in a bucket of cold water to keep it cool 😎☺️
That wouldn't be safe! Unless you earthed the bucket.😂
Gee, that’s a really good idea..,
And you can stick your finger in the water to see if it’s getting warm.
Just make sure you have no footwear on, to make sure you’re really ‘grounded’ !
Oh ! Just video all this; so we can make sure you’re getting electro.. ops, everything right !
@@tigerick7291 doh you have the earth in a bucket besides it water and earth in the same bucket's just mud 🤣
And you’ll have a nice bucket of warm water at the end of the day to wash your hands in 🙌🏻 🧼 🧽 😊
I didn't know that about transformas. Brilliant video.
Not cheap. I used a generator for most of my work, only used a tranny to fitting kitchens. Some great tips below so be nice to your unit. It's mostly battery if you've got 2 spare as a lot of sites expect you to supply your own power. General use 240v converters on site in various places helps. Cannot remember the last time I bought one mind...
had many 3kw transformers most overheat and burn out take off lid only 4 screws to allow heat to escape or buy a 4kw had the same one for over 10 years and its on all day as well it gets hot nut it gives me no problems
Plug a drill in transformer hold trigger in then switch on power to transform it'll limit surge and stop circuit breaker tripping in most cases
O dear so little knowledge is so dangerous.
I hate carrying those things around too. If I'm on-site, I try to use my cordless tools as much as I can.
Most important thing’s you need to know .they are heavy and when you get to 50 yrs , you think f*@k it I Im not doing it no more
If you need to use continuously employ two - then keep swapping between them.
Really interesting. 99% of people must abuse these then. I never knew they were for intermittent use but makes complete sense. All the heaters I have seen plugged into these and left running for hours……
If the thermal cut out is not opening then all is good. The ''continuous duty'' is lower than their intermittent duty rating, but it is a true continuous duty.
I'm transformed 😂😂😂
Didn't know about the intermittent use bit I'll be honest. What did annoy me in my 'days of on the tools' is the MCB nearly always kicked out on the consumer unit when you plug it in, especially in the winter when the tranny is cold. The customer thinks your plugging something dodgy in when you ask if they could pop in and reset it. 😊
A lot of start up surges need a particular type of RCD. I can't remember which
@@SkillBuilder Type C is better but not the sort of thing that is expected in a bog standard house unless it is designed for that type.
@@SkillBuilder Type C but no good when you're at a customer's house which would normally be type B.
Always try and plug into a B32 on the ring circuit or the cooker panel which should be a B32 or even a B40 if you are lucky
@@tinytonymaloney7832 Do you no if there is any reason why a type b MCB not be changed to a type c MCB ?
Top tip. Give it a cool down with a garden hose or a bucket of water if it starts to overheat.
Every time I turn up at a customer’s house needing to use one.
First thing I ask, where’s your fuse box. 😂
Why?
@@g7mks383
Transformers have a tendency to trip them out.
Happened many a time. 👍
Thank you : )
Lol burnt one out when I started as a labourer busting concrete with a breaker was wondering where the burning smell came from 😂
Only time I've known the thermal cutout operate was when we damaged a lead driving an access tower over it. The lead was sparking 😂 and most tools are nowhere near the max load of these trannys so can run continuously. 3kva is a lot! That's why they make the little 1.5kva (I think) units for single tools.
I hired a cement mixer recently. Got a 5kva tranny with it (all the hire shop had) and ran it all day, mixed up 1.2m³ continuously. Mixer was about 600w.
I recently bought a 0.5 kVA continuous / 0.75 kVA ''tool rating'' (i.e intermittent) second hand for £25. Much lighter than my 1.5 kVA/2.25 kVA I had previously, and I doubt it will ever trip in a life time with normal power tool usage, even flat out, even with 2 people if I had to guess. Unless you had a scenario were a prolonged high load like a mixer or such is used, I doubt it will ever trip. And I can always bring out the larger one for those few occasions. If I was a tradesman I would go cordless, but for DIY I can have a corded version of everything I need sitting on the shelf ready to go, without batteries deteriorating and eventually dying from lack of regular use.
Don't they have both continuous and intermittent use times? For example you can use it at 1000W all day long and 1500W for 30 minutes.
The defender one I have is rated 3000 watts 5 mins on 15 mins off or 1500 watts continuous, Ive just looked.
Does that mean they can last longer in the winter
I'm using one that's double the physical size, and also weighs nearly 3 times as much, to power my chop saw. Those little 16Amp transformers just don't have the power, and the chop saw hardly scratches the metal it's cutting. But using a 32Amp transformer, I can cut through quite a bit more, and unless the light fingered out there have a wheel barrow, it's not something your going to run off with.
Just seen a wee Scouser leg it up the road with the cement mixer and two bags of cement under his arms I kid you not haha and it was nailed down
Hi Roger, we all use electrical tool appliances so how would we get to maintenance and service test and certification
great info never new that about them good shout SB
Thanks roger
Have to admit when I use mine which is not all the time it's going for a few hours or more ,😏 but what do you do , good video 👍🇮🇪☘️👏
mines absolutely hammered... and a while ago i turned it on and the thermal switch went bang so it hasnt got a thermal switch now. ideally id move away and go cordless but then id need a new mitre saw as my kapex is 110v.... my track saw, extractors, routers etc are all 110v so thats a canny bill to replace all of that lot
Probably should of explained the purpose of a on site isolating transformer which I understand to be that you never get more than 55v between a conductor and true earth.
Yes maybe a 'How transformers work' is another video but we need someone clever to present it.
@@SkillBuilder John Ward explains it here: ruclips.net/video/fRhofcMyAyk/видео.html
Personally I would never go with a unit less than 10 kVA. The whole safety goal is defeated if the transformer melts down and the secondary comes into contact with the high voltage primary. What would you rather electrocution or a little bit of grunt moving a transformer? A small hand truck and it's never been an issue in all my years. On projects with 2 people running tools simultaneously I bring 2 of these. And the inrush current thing is overblown, a very simple fix with a soft starter that momentarily puts a lamp in series with the input power and is bridged a second later with a timed switch. The initial magnetisation current is limited by the resistance of the bulb and gets the flux swinging in the core, and then the bulb is bypassed and taken out of circuit afterwards.
In a world of RCD's and RCBO's it does beg the question, why are we still bothering with 110v?
No other country in Europe uses 110v and they don't seem to have any major safety issues.
More and more on site 110v is being replaced with 18v.
Isn't it about time this system is due for a review and the construction industry looks at protection at source being law.
I agree.
@@SkillBuilder Maybe do a short video about it Roger, we need some input from electricians on the pro's and con's.
Because if an RCD with 240 volts (and I do mean 240 not 230 ) doesn't trip for whatever reason, then you're dead.
If you're using 110 volt appliances and you come into contact with that voltage, you don't die.
Good time to talk about ...... Duty Cycle!
Leaving it plugged in will not cause overheating because there is minimal current flowing. Using it is another matter.
I think you'll find if you derate the transformer by the duty cycle then you can use it continuously.
For example if the duty cycle is 30% and the transformer is rated for 1,000 VA then you should be OK with a load of 300 VA using it continuously.
The cause of these issues is the transformer is made to be waterproof and to withstand the abuse of being on a building site. Put the same transformer in a metal box with louvres for ventilation and it'd probably run happily all day at rated load.
The other approach would be to buy a transformer that's got a higher power rating than you need. Of course that's going to cost more and be heavier.
Yes I was talking about a breaker running for hours on end. I understand a site light would be fine.
It's kinda linear. half load twice the time. It's not a welder, so they should all be rated 100% duty, but now every thing is cheaped out on. All trannys VA was rated full load, heat soaked forever run mode. Now it's have a guess, we didn't certify it, we just make it and deliver it to anyone on alibaba
@@SkillBuilder exactly, and I think it's also the point is not to have 5 guys working off one of these trannys with splitter boxes. One chippy using a skill saw and chop saw back and forth is fine as he using one tool at a time and not continuous
@@UberAlphaSirus I understand where you're coming from however remember this is a portable device. Weight is a factor as is cost. I just took delivery of a 20VA isolation transformer from,Ali. Price was right and 20VA is overkill for my needs. I'll check it with an insulation tester before I trust my life to it but it looks the goods with plenty of insulation between the windings. Transformers and motors seem pretty simple devices until they're not. The difference between 50Hz and 60Hz generally doesn't matter until you've got thousands of slurpy makers running on 110V at 50Hz via a transformer and the motors are not lasting all that long.
How are we suppsed to charge MEWPs onsite if we're supposed to give em 15 minutes rest after 5 minutes use????????????????
Please dont exceed its rated KWH rating, try to use one at least twice the watts of the tool being used. I have a 5KWH one for all day use and a light 1.5 one for the odd job.
There is no KWH rating for a transformer.
You are getting your units mixed up.
There is KVA, KW and KWH.
They are not interchangeable.
The only ones that apply to transformers in this set are KVA and KW.
With modern electrics and RCD extension leads will they eventually become a thing of the past and just have the 240v tools. I've been working in domestic land for a few years now and have switched over.... Probably going to get a bunch of flack for that but the vac runs the chop saw better and the rail saw. 110 only gives 800w from the vac. Or will it go just to heavy ass 40v Makita. Heavy though.
I like to sit my transformer on blocks to get air flow underneath to keep cool.
Goor idea, why don't they have feet?
@@SkillBuilder that is a question I have asked myself many times
@@SkillBuilder Because cold ground or concrete will work even better to get the heat out. I do remember an old german transformer that had optional feet that you can pop out.
Good to know, I'll still ramp it though no doubt.
I've watched loads of Transformers films.
I never knew Optimus Prime worked on 110v and could only do intermittent use.
When the Autobot Transformers are battling the Decepticons, they do 5 mins on and 15 mins off duty-cycles?
The Mrs cracked a similar one lol
Hang it up - air circulation improves a lot, but close to the ground is the coldest place.
I give this video a thumb up roger 🤣🤣
Guilty as charged, leave mine on All day, 🔥 down a 40ft tool Container ( 30+year's ago) back when I Was A Padwan 😩
Give it 15-20 years and they will be museum pieces...plenty of copper in them though, must be worth a few bob to weigh them in?
Should I buy a 110v mitre saw and buy a transformer to use for domestic or buy a 240v mitre saw and use a transformer and convert it to 110v for site use. I want to use it for site use and domestic use so what’s better? 110v or 240v
I did wonder why most of them were always knackered.
Mines on all day everyday no probs.
14 yrs old now no issues
It is not the fact that it is on it is the current it draws.
@@SkillBuilder
Yes reading the other comments, 1650w largest motor I use so yes that makes sense
How is your thumb getting on?
Also great that the maximum voltage to earth is 55v
Very good video Rodger , thanks !!
They come with instructions? 😬
What are instructions?
Good thing about them is once you’ve heated your kettle up, stand your cup on the tranny, keeps the coffee nice and toasty. #abuseanduse. #toptips
Interesting, but is it an autobot or decepticon
They are for continuous use at a lower load. That one you have the is rated for 3000w short term and 1500w long term. I use them on site to power festoon lighting and there on all day every day for weeks
Shit only things I ever noticed about them , they were heavy and yellow
@@malcolmfunnell4501 if you think there heave I have to use a 10 K
@@scottsparky1
I recon your a youngster Scott ,
Otherwise you would be moaning like us oldie’s😜
@@malcolmfunnell4501 not really I have a 20 year old apprentice that moves it for me
Due to the weight of my 3 KVA transformer I call it great Aunt Hernia.
As a site electrician working on huge high rise building sites in Sydney, I find this transformer idea a bit of a nuisance. I'm glad we don't mandate this madness here. We use 240v rated tools and are glad to do so. We do however require all electrical tools to be inspected monthly for damage.
I take it you use RCDs?
@@SkillBuilder stringently.
RCDs = residual current device, a circuit breaker that cuts the flow of electricity if an abnormality is detected, reducing the risk of electrocution
That must be why I’m on my third transformer in five years.
Then clearly you have no idea on how to use one by abusing it.
From Aus and thought you had 240VAC at 50Hz in UK……so why buy 110VAC stuff and not just 240V equipment like here……??
my wallpaper stripper is 110v cannot really use it intermittently when stripping a house. and yes the transformer gets super hot and did trip the other day. seems like it was a daft idea to make a 110v wallpaper stripper (it also has a big water tank)
I have a stripper that’s 110 and she is very wrinkly
perhaps a daft idea to buy a 110V wall stripper unless you must have one!
How far does the 110v rule apply though every site is different, some sites say your cordless tools must be charged on a 110v charger so you still need a transformer others will have a container with loads of 240v sockets in ? It's hit and miss.
the ones that say you must charge batteries via 110v don't work for them, they're called nonce sites and the site manager is the biggest nonce of them all.
Yes it is erratic and it is not even a legal requirment to use 110 volts.
@@garnhamr ?????
Alright Richard
I used to wonder why my father always sat the transformer on a concrete block when it was used inside
Maybe I have just been luck my transformer is plugged in all day and gets used for way longer than 5mins and I have never had to use the thermal switch.
It depends what current you draw
Didn’t know that
transformer in one hand, mitre saw in the other, and I am balanced, but I can't walk through doors
3300VA Intermittent Rating 5min on/15min off ,1650VA max Continuous Rating all day long
I always thought that if you had to use with extension leads you had to have the transformer plugged directly into the socket, and then use 110v extension leads, not plug the transformer into a 240 extension lead like in your clip of the breaker as the drop in resistance along the 240 extension lead damages the transformer.
No, electrically, there is no problem at all plugging the transformer into the extension lead. There is less current being drawn on the 240V side, so the voltage drop is likely to be less, do make sure that you have fully uncoiled the 240V lead though. On the 110V side the current will effectively be doubled, so you need a heftier extension lead, especially if running long distances.
On some building sites however, there will be a policy of plugging the transformer into the socket and running the extensions in 110V. This is because the transformer is wired so that there is only 55V to earth on the 110V side, so if the extension lead gets damaged, the danger is much less to the workers, than if a 240V extension lead is damaged, that would have the full 240V to earth.
do you want a job? we could do with an electrician
It is much safer to run 110V around on extensions than it is to run 230V.
@@davidbrewer7937 It is illegal to run 240v leads round a site.
@@charlieb6001 And rightly so....
5KVA transformers are better plus all CE Rated transformers come with a thermal protection device fitted.
5KVA are no good in most domestic settings as they’ll normally trip the B Type MCB when switched on due to inrush current but, should be fine in commercial/industrial locations.
There’s no legal requirement to run 110V on sites however, most larger scale sites do require it & should provide industrial/vented transformers as part of their onsite installations for contractor use if they specify it’s requirement.
Cordless doesn’t yet have the longevity for disc cutters/breakers & prohibition of combustion engines indoors should rule out that option for most so, transformers will still be with us for a while at least.
Not much else that a battery doesn’t run on site these days. Might be worth people following your lead & adopting cordless solutions.
There are now Cordless Milwaukee and Dewalt concrete breakers and saws, and new cordless Hilti Concrete saws as well, pricey though.
What is the point in 110 anyway?
Keeping people alive
@@SkillBuilder how so was my question. It's obviously a safety thing but not sure the point.
Same thing happened to me with a laser level. It was screwed to the wall in a customer's house. There was only me and one other builder. When I went back the following day The laser level was gone and he said exactly the same thing laser level. What laser level? I've not seen a laser level.
You can never rule out the customer stealing it. That has happened to me. I did some work in a drug rehab unit and everything in my tool box was a potential fix.
@@SkillBuilder Worked in one of the busiest Garda stations in Ireland as an apprentice Carpenter. First day we arrived the guy who looked after the facilities told us not to leave any tools down these are the biggest thieves going.
They literally are 240v to 110v, I am shocked there are not lighter, smaller alternatives.
I never knew they didn't have 120 in the UK.
Why don't they have 120?
240v in the UK. Man's electric.😀
110v is only really used in industrial settings and building sites. You won't find it on houses like the states 120v. It's also centre tapped to keep touch voltages low so it 55v - 0v - 55v.
@@effingandjeffing8270 US also use 240 when needed. See Technology Connections.
My guess is that someone looked at current loads and decided that having a higher voltage meant they can get away with less current. Lower current means smaller wires and copper was not in great supply at the time people were looking at it. The us also has 240 for some things like dryers and car chargers but it’s done with a split phase so 2x 120 combined I believe. We tend to use 3 phase when we have big power loads and generally that tends to be in industrial setting and so we end up with smaller copper again.
@@effingandjeffing8270 most people don’t seem to realise this 55v shock to ground is why 110v its safer than 240v.
That sounds like the manufacturers get out clause
Take a day off Roger 🤣🤣
I just did
@@SkillBuilder 😆
Why don't Brits develope power tools that do not require transformers? Rented one to power a German made roto hammer with an American (110) plug while building an extension in Scotland year 2000. Very inconvenient.
We require 110 volt tools, for safety reasons.
Now tell me how you are going to get 110 volts from our 230 volt electrical system without using a transformer?
I would love to hear your answer.
Or now days use a Beaker on 240v with a rcd
Y'all need a bigger transformer!
I’ve got two and they randomly work and don’t work ! Have to take two because they are so unreliable
Why not just use 230 v tools with an 30 ma Rcd plug🤔.
It's not often you would be drawing 3kw of it for any prolonged period so you shouldnt have to keep unplugging it really under normal use. I mean really, who does that?
for example a 110v wallpaper stripper you would use that pretty much continually.
You don't need to unplug it, just stop drawing current.
110 v transformers are actually 55 v if you measure the voltage it's because it's a center tapped transformer
55-0-55 is the term.
But the appliance requires 110 volts which is why it is referred to as a 110 volt transformer.
It would be pretty crap if we have 110 volt appliances being fed from a 55 volt transformer. Think of the confusion and mistakes that will occur.
And you can get a 110 volt shock if you contact across both live terminals/wires on the secondary. Though that is less likely to occur than a line to human/earth situation.
Robots In Disguise.
I always thought transformers were robots in disguise.
To reduce equipment losses engrave your tools: 'STOLEN from Roger Bisby' - and use a permanent marker pin to fill the engraving. It will reduce thefts but may end up with everybody marking their tools with your name - can't win!!
Sounds like there's a gap in the market for an improved design
The main thing you need to check and consider is that it may be……
…. A Robot in disguise
If david moyes an gollum had a kid it would look like this fella