A precaution step: after power it up, put your AC test pen on the PSU casing, to see whether there is any AC current on it, before touching it, just a thought :)
Awesome video man. And great job checking everything out before applying a load to it. Funny short story. Years ago I watched a Chief Engineer fry a power unit for a Rolls Royce azimuth pod worth about 50 grand at the time all because he didn't check everything out before hooking it up. Turns out the damn thing was internally shorted right out of the box. That has stuck with me ever since. It pays to double and sometimes even tripple check your equipment before putting it in service. Again awesome video. 👍
Thanks for the video. This probabley an obvious point, but, you are handling this unit in a very casual manner. I hope everyone realises that the two unprotected screws with the innocent looking black and white wires will probably kill you if you accidently touch them!
My understanding is that connecting V- to GND gives the same voltage there. 12V between V+ and V- means that the difference between the two is 12 but doesn't tell you anything about the two separate values. Once V- is connected to GND (which usually is 0V) this will force that end to that value (not sure about V+ though)
what is the use of hooking up the V- to gnd i usually just leave it floating but my application is just for electrochemistry so idk though i do also use a meanwell psu for that
Hi, I bought 24v 15a power supply. Can you tell me what gauge wire I need to use to connect the power supply to my 2.1 amplifier and also from 2.1 amplifier to speakers ? Amplifier will connect 160w*2 + 220W. Please advise. Thank you.
WhileI appreciate the idea of soldering your power wire ends, it's considered quite unsafe. There are numerous images of fires (printers and houses) due to this. What happens is that, if there's a crazy issue or current draw that makes the wire(s) get very hot - hot enough to melt the solder, you now have a connection(s) that have melted the solder out of the joint (and possibly shorting something all by itself) which leaves you with a screwdown connection that isn't tight anymore now. It's loose - quite loose without the solder which makes it start arcing and sputtering. Wire ferrules, is the right way to do it. Ferrules or nothing at all. Like I said, though, I completely get the impulse to solder them.
audiophilestyle.com/forums/topic/37034-smps-and-grounding/#comments. I read about it on this link pertaining to Grounding DC output negative side to an ac plug ground side. Something to do with leakage current.
FOR THOSE USING 110 AND A BATTERY I USE THESE ON MY RV AND MY BOATS. ONE OF THE 12V SETS GOES TO MY LIGHTING ETC. THE OTHER GOES TO A BATTERY. IF YOU UNPLUG THE 110... EVERYTHING RUNS OFF THE BATTERY. WHEN IS PLUGGED TO 110 IT KEEPS THE BATTERY CHARGED UP. JUST FYI DO NOT CONNECT THE V- TO THE GND!
Hello. I bought a 650 watt psu which came with a 16 amp power plug but unfortunately i cant plug tht into the socket. Is it okay if i use the 10 amp plug from my previous PSU or will that cause any issues?
Awesome thought it was that simple to power these up. I have a 48V power supply for my pinball machine that will run the boards and the flippers on my pinball machine. :)
I have a power supply like this i use it to run my kl Italy 207 connected to my galaxy dx 949 but when i turn on the power supply i get six pounds of loud static noise in my cb.
I have an IEC320 c8 power socket with a rocker switch( 3 prong top and 4 prong switch on bottom) mounted on the wall of an ammo box. I'd like to wire it on the inside from that plug to the power supply. Could you post the wiring diagram or a video?
I'm planning an identical project. My computer power cord has a bare 4th wire that I understand is the ground for the tinfoil shielding in the wire bundle used to prevent interference in computers. Do I need to do anything with this wire or can it be left unconnected?
I have this same psu and thanks for showing how to hook it up. Always better to see it done than trying to figure out directions. So from the comments , am I correct to assume you don't hook up that small green wire like that anymore, just skip that part?
Hi John I have a question for you. I just got to CMB 24 for RGB dumb nodes and wired a brand new power supply similar to the one in your video with the fan and vents on it. I noticed that it works perfectly with no issues but in the Lor Hardware utility when it goes from 0 to fade it makes a slight sound and smells like burnt Electronics but it only lasts a few seconds. Out of caution I shut it down waited a few minutes tried it again and it does the same thing while previewing a sequence. It begins to emit a slight Electronics smell is this normal or would you suggest that as a bad power supply and try something else? Also on a side note I just want to thank you for all your videos you have really helped me over the last couple years with your videos.
Won't that trip a circuit breaker when it gets to 20 amps? I never understood why they sold a 60 amp power supply since most jacks are mapped to a 15 amp circuit breaker.
so this is 12 volt only out, not plus/minus 12volts , as would I need a 24 volt same type power supply and get the needed +/- 12 volts for + 12volt rails and -12 volt rails?
V- is negative. Unless you're seeing something I'm not I believe he did everything right in the demo even down to checking output voltage before loading it. I wanna say that's universal for DC systems with Red being positive or V+ / +V and black being negative or V- / -V whichever the label shows. I'm pretty sure I'm right on this, but if I'm not please correct me. Hope this helps.
I wanna say it's a global standard, but I could be way off. Definitely an American standard as well as the UK. I would double check Google on the rest though. I don't wanna stear you wrong with bad info
just my opinion but I build big power supplies using multiple of these and you usually never want to hook the negative 110v in to the negative 12v out..
+Cameron Mataya : Thanks. I've only seen this done on a PSU that was pre-wired up by SanDevices and no where else. I've stopped doing this as well. I should annotate the video.
I agree, I use these as dc-dc converters for ev conversions. If the negative and ground are jumped, than the hv pack negative becomes part of the chassis ground and if there is a HV short, it will arc off of the chassis. Keep the input and output ground isolated to prevent fatalities.
Is the 20V AC or DC setup? I set my multi to DC and got 12.30 DC, but when I switch to AC the numbers just bounce around. Is it supposed to be 12.0+ on AC or DC? If it's AC I just got the earth and ground wires switched (I made my own plug and the wires were not labeled) Thank you
@@listentoourlights If I may ask, when doing power injections I have my 22/4 wire which is RGB and black wires, which of the 4 wires get screwed down on the power supply positive and which to the negative? I assume 2 wires are positive and twisted together then put on the post, then 2 are negative, twisted together for the negative?
@@wyattspop For power injection you only need two wires. One for positive and one for ground. Most people will get a power distribution board that will take power from the PSU and then have multiple fused outputs for power injection. pixelcontrollers dot com is where I get mine
hi, I liked the video.can i use this power supply to a car amplifier which needs 12v 60A power, so that i could connect two +ve and two -ve output to the amp?
May I ask what AWG's are suitable for this kind of PSU? My PSU type is S-15-24 (0.7A output current) and I'm not so sure what AWG's should I use. Nice video btw.
Yeah, don't wire V- to GND. When I bought my first controller I bought it assembled and this is how it came from San Devices. However; you don't want to connect these two.
I have the same. I have no idea if you are using the same rocker switch as myself, but if you look at the bottom of the switch with good lighting, it should be written ( L / N / ⏚ ). In my case it is ( Red = L / Blue = N / Yellow = ⏚ ). Again, no idea if the same switch, so it is always important to double check. Hopefully you have this long figured out already, and this is just reference for anyone else who maybe sees the comment. :)
@@alexthomas6602 I got a 30 amp supply from amazon, same as in the video, but over top of the indented marks on the aluminum was a sticker covering all of the marks in the metal (N,L,+,-) and the sticker had the N and L reversed. Isn't that something.
why are there 2 sets of outputs? Can this ps power up more than one device at a time. Why did you loop the positive end of and output to the ground, is it because you're only using 1 output. I dont know much about electronics, just curious.
The V- is looped directly to ground. This is probably to make life easier since whatever you hook up to the DC voltage needs to somehow have its ground connected to the ground of the PSU. My guess is that by doing it like this you guarantee that this will automatically be the case and you don't need to connect those separately.
VstaarProduction 15 "L" = "Line" which is AC power coming IN, whereas the LOAD is going out - i.e. whatever the power supply is running at 12VDC. The Chinese really should mark these things better. senior frog nailed it
I wish I have the one you had because my other dc power supply is mess up.wacth this on my old channel: my dc power supply failure overvolt type it on the search box on RUclips 🙁
I could not help but think that if you need to explain the colour codes for 240VAC hook up then your audience should keep clear. You do need a minimum knowledge to connect mains power safely. How do you expect novices to have any idea about adequate wire size for different currents.
Peter Owens I have no idea about colour codes but I'm pretty sure I know how to hook this up :D I intend to just continuity check the cable to see which wire came from where on the original plug 👍
If you want some more information on the wire between DC negative and earth ground, check out the video EEVblog #279 - How NOT To Blow Up Your Oscilloscope!" here ruclips.net/video/xaELqAo4kkQ/видео.html
Not Cool Bro No, "LINE" is POSITIVE (+) power in, "LOAD" is POSITIVE (+) OUT. Look at the correct wiring diagram for a GFCI outlet, and you'll understand
When you fix up your screw up of bridging the AC and DC grounds, you might also want to point out that "L" does not stand for LIVE - It's LINE or LINE IN (basically the same, but get it right) and while you are at it, Caution users that BLACK on the AC is a HOT or + connection. On DC, RED is Hot or + connection and black is Ground. A LOT of people confuse this an if a moron does things wrong, they could become a candidate for the Darwin Award.
You should not be teaching anyone this unless you state and point out associated electrocution hazards ie bare mains power connections easy to touch and also don’t use the jumper cable you have between the grounds
A precaution step: after power it up, put your AC test pen on the PSU casing, to see whether there is any AC current on it, before touching it, just a thought :)
Kugan Kumar my thoughts exactly. These types of PSUs make me so uncomfortable because the whole damn thing is conductive.
Steven H Wrong, that’s what earth ground is for. If a wire or something touches the casing it will get grounded.
Awesome video man. And great job checking everything out before applying a load to it. Funny short story. Years ago I watched a Chief Engineer fry a power unit for a Rolls Royce azimuth pod worth about 50 grand at the time all because he didn't check everything out before hooking it up. Turns out the damn thing was internally shorted right out of the box. That has stuck with me ever since. It pays to double and sometimes even tripple check your equipment before putting it in service. Again awesome video. 👍
Thanks a bunch. I've now set up mine and added that bridge on the negative connections. 5v 40A in my tp4056--20X 18650 charging station. 👍👍
Thank you so much, i was planning on using one of these (5v) for my pi's cluster
Thanks for the video.
This probabley an obvious point, but, you are handling this unit in a very casual manner.
I hope everyone realises that the two unprotected screws with the innocent looking black and white wires will probably kill you if you accidently touch them!
It would be very rare for it to kill you. Most of the time it would burn you and knock you on your ass.
@@ryanavery7980 That depends on if it is 240v or 110v. The exposed terminal are very dangerous
This video helped me so much, I didn't know anything about powering something and now I know how to do it.
My understanding is that connecting V- to GND gives the same voltage there. 12V between V+ and V- means that the difference between the two is 12 but doesn't tell you anything about the two separate values. Once V- is connected to GND (which usually is 0V) this will force that end to that value (not sure about V+ though)
I tried to connect the grnd to v- but the entire unit becomes grounded hahahaha
what is the use of hooking up the V- to gnd
i usually just leave it floating
but my application is just for electrochemistry so idk though i do also use a meanwell psu for that
most have those ground jumpers inside, if just bought one and mine was rattling around inside so had to connect it
Hi, I bought 24v 15a power supply. Can you tell me what gauge wire I need to use to connect the power supply to my 2.1 amplifier and also from 2.1 amplifier to speakers ? Amplifier will connect 160w*2 + 220W. Please advise. Thank you.
WhileI appreciate the idea of soldering your power wire ends, it's considered quite unsafe. There are numerous images of fires (printers and houses) due to this. What happens is that, if there's a crazy issue or current draw that makes the wire(s) get very hot - hot enough to melt the solder, you now have a connection(s) that have melted the solder out of the joint (and possibly shorting something all by itself) which leaves you with a screwdown connection that isn't tight anymore now. It's loose - quite loose without the solder which makes it start arcing and sputtering. Wire ferrules, is the right way to do it. Ferrules or nothing at all.
Like I said, though, I completely get the impulse to solder them.
Anyone know where I can find more information on that ground jumper wire?? Is it necessary safe and why?
audiophilestyle.com/forums/topic/37034-smps-and-grounding/#comments.
I read about it on this link pertaining to Grounding DC output negative side to an ac plug ground side. Something to do with leakage current.
How to covert batery power in 12v to out 220 use that inverter
Is it OKAY to connect a switch-inlet ground and a case ground to the FG post on your power supply?
seems a lot like the husky replacement power cords you can get from lowes, pre-dipped in solder. But no judgement lol, they work great.
Can use L and N wire only to power the power supply?
FOR THOSE USING 110 AND A BATTERY
I USE THESE ON MY RV AND MY BOATS.
ONE OF THE 12V SETS GOES TO MY LIGHTING ETC.
THE OTHER GOES TO A BATTERY.
IF YOU UNPLUG THE 110... EVERYTHING RUNS OFF THE BATTERY.
WHEN IS PLUGGED TO 110 IT KEEPS THE BATTERY CHARGED UP.
JUST FYI
DO NOT CONNECT THE V- TO THE GND!
What garage wire is that ?? What’s to low and what’s to high? 10? 12? 14??
Hello. I bought a 650 watt psu which came with a 16 amp power plug but unfortunately i cant plug tht into the socket. Is it okay if i use the 10 amp plug from my previous PSU or will that cause any issues?
What would happen if you accidentaly touched the live screws?
💀
Awesome thought it was that simple to power these up.
I have a 48V power supply for my pinball machine that will run the boards and the flippers on my pinball machine. :)
I have a power supply like this i use it to run my kl Italy 207 connected to my galaxy dx 949 but when i turn on the power supply i get six pounds of loud static noise in my cb.
Helo. Can i use the 12volts power supply commect to inverter 12volts to 220 ?? Thats why i can safe electricity. Thanks for answer to my question.
There are 220v input / 12v output versions of the power supplies that you can buy.
I have an IEC320 c8 power socket with a rocker switch( 3 prong top and 4 prong switch on bottom) mounted on the wall of an ammo box. I'd like to wire it on the inside from that plug to the power supply. Could you post the wiring diagram or a video?
Don't forget to set your incoming voltage to either 220 or 110, my unit has a switch on the side.
I've got tdk lambda 60w psu. I connected LN and it shows Green Dot green light on psu. does this mean I can proceed next step ?
Thanks to this video i now I have my own power supply..
I'm planning an identical project. My computer power cord has a bare 4th wire that I understand is the ground for the tinfoil shielding in the wire bundle used to prevent interference in computers. Do I need to do anything with this wire or can it be left unconnected?
I have this same psu and thanks for showing how to hook it up. Always better to see it done than trying to figure out directions. So from the comments , am I correct to assume you don't hook up that small green wire like that anymore, just skip that part?
Hi John I have a question for you. I just got to CMB 24 for RGB dumb nodes and wired a brand new power supply similar to the one in your video with the fan and vents on it. I noticed that it works perfectly with no issues but in the Lor Hardware utility when it goes from 0 to fade it makes a slight sound and smells like burnt Electronics but it only lasts a few seconds. Out of caution I shut it down waited a few minutes tried it again and it does the same thing while previewing a sequence. It begins to emit a slight Electronics smell is this normal or would you suggest that as a bad power supply and try something else? Also on a side note I just want to thank you for all your videos you have really helped me over the last couple years with your videos.
Mine stopped working yesterday out of the blue. Is there a reset button on it?
Can this thing charge a car battery at14,4 volt?
Won't that trip a circuit breaker when it gets to 20 amps? I never understood why they sold a 60 amp power supply since most jacks are mapped to a 15 amp circuit breaker.
so this is 12 volt only out, not plus/minus 12volts , as would I need a 24 volt same type power supply and get the needed +/- 12 volts for + 12volt rails and -12 volt rails?
Will this turn on without an earth (ground) and just the live and neutral wires?
Hey why did you place black wire into -V?
V- is negative. Unless you're seeing something I'm not I believe he did everything right in the demo even down to checking output voltage before loading it. I wanna say that's universal for DC systems with Red being positive or V+ / +V and black being negative or V- / -V whichever the label shows. I'm pretty sure I'm right on this, but if I'm not please correct me. Hope this helps.
@@zackthomas5707 Oh thanks. Is this american standard or european?
I wanna say it's a global standard, but I could be way off. Definitely an American standard as well as the UK. I would double check Google on the rest though. I don't wanna stear you wrong with bad info
my power supply doesn't stay on and I'm trying to figure out why
just my opinion but I build big power supplies using multiple of these and you usually never want to hook the negative 110v in to the negative 12v out..
+Cameron Mataya : Thanks. I've only seen this done on a PSU that was pre-wired up by SanDevices and no where else. I've stopped doing this as well. I should annotate the video.
Cameron Mataya he is hooking up ground to ground, not negative to negative
I agree, I use these as dc-dc converters for ev conversions. If the negative and ground are jumped, than the hv pack negative becomes part of the chassis ground and if there is a HV short, it will arc off of the chassis. Keep the input and output ground isolated to prevent fatalities.
Can you link the two 12 volt outputs in parallel to double the amperage and increase the length of led strip you can use?
I would like to know as well ! Did you find out ? Thanks
thanks for making this video
Whats the wire gauge your using
Thank you for the explanation. Very clear!
Is the 20V AC or DC setup? I set my multi to DC and got 12.30 DC, but when I switch to AC the numbers just bounce around. Is it supposed to be 12.0+ on AC or DC? If it's AC I just got the earth and ground wires switched (I made my own plug and the wires were not labeled) Thank you
12 volts output DC
@@listentoourlights Perfect, thank you, I got it to 12.03 V at each terminal
@@listentoourlights If I may ask, when doing power injections I have my 22/4 wire which is RGB and black wires, which of the 4 wires get screwed down on the power supply positive and which to the negative? I assume 2 wires are positive and twisted together then put on the post, then 2 are negative, twisted together for the negative?
I had planned to "inject" that wire between strips 1 and 2by T-ing them off (snap connectors)
@@wyattspop For power injection you only need two wires. One for positive and one for ground. Most people will get a power distribution board that will take power from the PSU and then have multiple fused outputs for power injection. pixelcontrollers dot com is where I get mine
Wonder why there are two V+/ V- screw down terminals?
so you can connect several wires into it (eg, if you're powering different components off of that single power supply)
Do you recommend the Light O Rama power suppy for the CMB24D?
The first to do b4 wiring is to set and match a switch to your country voltage
(220v or 110v)
i see you have a Smun power supply. how's it holding up so far?
Does anyone know what plug fuse would be suitable to use for a 12v 400w 33A power supply?
DO NOT TIN YOUR WIRES, the heat can cause the solder to melt and the wires will slip and cause a fire
Hi, I was wondering how many devices can it hook up to those V+ and V- ?
I think it depends on the amps of what you’re using
hi, I liked the video.can i use this power supply to a car amplifier which needs 12v 60A power, so that i could connect two +ve and two -ve output to the amp?
palanivelu sivakumar did you figure this answer out? I'm looking to do the same thing
palanivelu sivakumar
NO!!!
360W = 30A @ 12VDC
Get a 75a model.. They're only like 12 bucks from china.
Great video, very helpful! Thank you!
May I ask what AWG's are suitable for this kind of PSU? My PSU type is S-15-24 (0.7A output current) and I'm not so sure what AWG's should I use. Nice video btw.
+LiveYourLife I use 12 or 14 guage wire from the PSU to the controller. 18 from the controller to the lights.
+listentoourlights Thanks, I will keep that in mind.
You never know.
It depends on the length of Run... larger wire for longer Runs, but don't go smaller than 18
How do you know witch one is witch?
Thank you, some notes; you should not talk behind the microphone. It's hard to hear you, but everything else is upper loud for headphone users.
I'm not an electrician, this isn't even my hobby, but I'm going to make a video about it anyway ;)
can multiple LED controllers be connected to the same V-/+?
Victor B Yes, you would just need to make sure your PSU can provide enough amps for your application.
what was the sense of the ground to the v minus?
Yeah I want to know this too
Yeah, don't wire V- to GND. When I bought my first controller I bought it assembled and this is how it came from San Devices. However; you don't want to connect these two.
I'm going to remake the video
how to wire it up if Im using a panel toggle switch?
So can you hold your DC wires directly into the V?
I have a solenoid I’m trying to use
The live terminal is unprotected and could kill you.
You should point that out.
Don't stick your tongue on it to test for voltage. Otherwise it's fine! Be smart people! :)
0:55 can someone explain why V- is jumped to GND please? Is this safe?
yeah, don't do that.
@@listentoourlights lmao thanks! But why?! What was this doing? Why not? Sorry, just trying to understand 😅
Can I touch it even if it's disconnected? Or is it always live?
erika hernandez If it is disconnected, there is no electricity.....
erika hernandez it shudnt be live
if you ever open electronicks be carful of high voltage capasitors tay can fuck you up bad
I’m thinking about making this for a Tesla coil to empower the house with energy without paying a light bill
I have a red, blue and yellow/green wire, and idk how to connect it
Do a google search on AC color code standards
I have the same.
I have no idea if you are using the same rocker switch as myself, but if you look at the bottom of the switch with good lighting, it should be written ( L / N / ⏚ ).
In my case it is ( Red = L / Blue = N / Yellow = ⏚ ). Again, no idea if the same switch, so it is always important to double check.
Hopefully you have this long figured out already, and this is just reference for anyone else who maybe sees the comment. :)
i prefer power supplies that have plastic cover over the connections, it's safer
what if you live in the eu andnonoy 2 wires come from the wall?
I'm not sure you could use this power supply. The systems run on different voltages.
So, why the wire from Ground to -V?
I bought a ready to go San Devices controller and that's how they wired it up. I thought it was the way to do it, but I quickly topped doing this.
is it ok to interchange between L and N? does it have polarity?
No do not do this l is live or positive n is neutral or negative if you want blue smoke go ahead
@@alexthomas6602 I got a 30 amp supply from amazon, same as in the video, but over top of the indented marks on the aluminum was a sticker covering all of the marks in the metal (N,L,+,-) and the sticker had the N and L reversed. Isn't that something.
very good!!!
thank you
why are there 2 sets of outputs? Can this ps power up more than one device at a time. Why did you loop the positive end of and output to the ground, is it because you're only using 1 output. I dont know much about electronics, just curious.
There is actually 3 outs.. 3 V+ and 3 V-. This can power 3 devices. Not sure why he did that to the ground.
Thanks
The V- is looped directly to ground. This is probably to make life easier since whatever you hook up to the DC voltage needs to somehow have its ground connected to the ground of the PSU. My guess is that by doing it like this you guarantee that this will automatically be the case and you don't need to connect those separately.
Just to point out L is NOT live it's LINE as in power line !!
Senior Frog it actually stands for load
Patrick Donovan
on these models from China, "L" means LINE - i.e. POSITIVE = HOT WIRE in from the AC.
Patrick Donovan NO!!! Load is the *load* you have on it!
VstaarProduction 15
"L" = "Line" which is AC power coming IN, whereas the LOAD is going out - i.e. whatever the power supply is running at 12VDC.
The Chinese really should mark these things better. senior frog nailed it
I wish I have the one you had because my other dc power supply is mess up.wacth this on my old channel: my dc power supply failure overvolt type it on the search box on RUclips 🙁
I could not help but think that if you need to explain the colour codes for 240VAC hook up then your audience should keep clear. You do need a minimum knowledge to connect mains power safely. How do you expect novices to have any idea about adequate wire size for different currents.
Peter Owens I have no idea about colour codes but I'm pretty sure I know how to hook this up :D I intend to just continuity check the cable to see which wire came from where on the original plug 👍
I took a electronics class, and I still don't have an idea on what wire gauges to use. I do know how to do some pretty hard circuits though
12 gauge would work fine....
Thanks!
Shukria
Can I keep one lol
If you want some more information on the wire between DC negative and earth ground, check out the video
EEVblog #279 - How NOT To Blow Up Your Oscilloscope!" here ruclips.net/video/xaELqAo4kkQ/видео.html
L means line
I'm not sure what they call it where you are, but where I am, its called line
+Riley Boon or it could be Load ?
Not Cool Bro
No, "LINE" is POSITIVE (+) power in, "LOAD" is POSITIVE (+) OUT.
Look at the correct wiring diagram for a GFCI outlet, and you'll understand
L is Love xD
L actually stands for
"THERE ARE TOO MANY WORDS THAT START WITH THE LETTER L"
When you fix up your screw up of bridging the AC and DC grounds, you might also want to point out that "L" does not stand for LIVE - It's LINE or LINE IN (basically the same, but get it right) and while you are at it, Caution users that BLACK on the AC is a HOT or + connection. On DC, RED is Hot or + connection and black is Ground. A LOT of people confuse this an if a moron does things wrong, they could become a candidate for the Darwin Award.
Is that we he did by jumpering v- and GND? Is this dangerous?
Doesn't mean live it mean line/black neutral is white green ground. no need for a jumper it is grounded inside the unit ALREADY OR IT WOULDN'T WORK.
NO. The outputs are isolated from the case.
You should not be teaching anyone this unless you state and point out associated electrocution hazards ie bare mains power connections easy to touch and also don’t use the jumper cable you have between the grounds
is the screw whitch holds live in place under voltage?? or is it isolated
If you lay a wire across them, it will arc, blow a breaker, and melt something.
Thanks!