Rewired Condenser with a Buck-Boost Transformer
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- Опубликовано: 27 сен 2024
- Eric Mele shows us a condenser that he has adjusted. He also added buck-boost transformers in the “boost” configuration. The incoming power supply is low, so the boost configuration increases the voltage from primary to secondary.
The condenser fans have been rewired. In the current configuration, the failure of one fan won’t take the other fans out. However, our main goal is to prevent fan failure altogether.
We have moved the circuit board over to make room for the buck-boost transformers. Eric installed two transformers and drew out the schematic on the panel so that future technicians can understand how he wired those transformers. The left of the schematic represents the low-voltage incoming power, and the right side shows the high voltage.
From line 1 to line 3, we only measure 201 volts on our incoming power. From line 1 to line 2, we measure 197 volts, and line 2 to line 3 measures 202 volts. However, with the help of the transformers, line 1 to line 2 boosts up to 222 volts. Line 2 to line 3 measures 217 volts with help from the transformer, and line 1 to line 3 measures 221.
We also have a control transformer tied into the low-voltage side of the system, and we get 200 volts to that transformer.
Anytime you make changes to the wiring of a condenser, keep the old wires with the system in case anything needs to be rewired. Create a schematic diagram as Eric did and make sure you provide all the important information that the next technician needs to know.
Our overall goal is to improve motor longevity. Motors can be expensive, so we want to minimize preventable costs and equipment casualties as much as we can.
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Neat!
I believe that I always learn something from you guys. Keep up the good work and thank you all for sharing.
Nice very good job. You learned me a thing or two about tying in xfmrs to existing equipment. Also very clean work!!
I wish you you would talk about the function of buck boost and why there were installed in the first place.
Thanks
So many people do not know about these buck'n boost Transformers they have small ones for like a single 240V compressor you need to put in a corner of a shop that has 208 existing there already, there's many use case scenarios for these things. And for smaller things you can get something with automatic switching on a multi-tap Transformer. I got one on my computer that's a battery backup ($120ish at Costco) power supply and multi-tap Transformer built into it to switch voltage up or down on-the-fly. And when out of range of transformer taps it goes to battery backup.
Of course they have the same for bigger stuff but much more expensive especially if they have generator or backup battery bank system.
I wish he would have shown an open panel on the buck's boost but I get why not show it on RUclips either. At least we saw a partial schematic.
This is good information except the owner really should contact the the Utility company first for a couple of reasons. First, to validate incoming voltages and second to make them aware of this issue because it could be an overloaded Utility transformer at certain times of day.
If the voltage at the Utility transformer is 120/208 then the issue is downstream of the Service transformer and will only degrade with time and load.
Customer will not be happy if you install all these buck transformers and the real issue was not first identified. What KVA Buck/Boost were used?
I was thinking the same thing. There was a couple of instances where I had the customer contact the utility company for low voltage feeding the building causing equipment to shut down. All was fixed in an hour. However, the situation may be different at this facility. The customer may be paying for a higher voltage feed to the building (480v, 11Kv, etc.)piece
I used one on those on a slushee machine once, worked pretty good
So your motors are rated for 208/240 service and you've put your boosted voltage at the top of the NEMA 200v (208v service) 20% bandwidth (220v) when the incoming line voltage is around 200v since that's kind of in the middle of the overlapping NEMA 200/230 bandwidths? And that gives you a surge buffer to the 253v top of the NEMA bandwidth for 230v ratings and likely keeps you from spending too much time with low end voltages on the motors. It helped a lot when I found a short write up on US voltage tolerance standards and started considering the bandwidths that are permitted. Never considered it but for a 200/230 rated motor, there's likely that 30v bandwidth is probably the sweet spot for the motor.
good job
Would be nice to know some general info of the site:
What type of condenser fan motors they are, just a simple 3-phase induction motors or ECM?
Is there any speed controllers, I don't see any VFDs so maybe a PWM signal to the ECM motors?
If there is a VFD controlling the motors, is there a shaft grounding ring?
What type of failures are you running in to, just electrical or bearing failure?
What is the average age of the failed motors?
How low have you seen the incoming voltage?
Is the entire building experiencing low voltage?
Was there ever a voltage recorder installed to monitor voltage fluctuations and phase imbalance?
Did it help?
How much is "quite expensive"?
Can you tell me what brand and model transformers you used?
I would have the site owner call the utility company. Offen times they can just pull the transformer fuse, adjust the tap changer and pop the fuse back in and dome in less than ten minutes.
That level of drop is unacceptable.
What’s happens when the voltage coming in goes back up during non peak usage? Doesn’t the output of that 200 lb ginormous buck n boost setup voltage go up? How are u limiting power fluxation?
In this case, the guy probably took a tending power measurement on a day that's hot and has heavy load on grid or done over long period of time like a week or month and then he picked a range that best fits the tolerance of equipment.
I'm guessing this guy did something like that and set the voltage correctly so when demand was low the voltage wouldn't be out of range. We know he set it to the proper boost tap, he just confirmed output.
But they do make auto switching ones that have the built in automation and everything for the situations that have more drastic voltage swings. Mostly I have seen them on server racks or dedicated circuits on cubicle stations for the computers.
This is what I think we (hvacr technicians) should be hooking up to any system that has vfds, or any fancy automation that requires decent power.
Biggest battery backup system with multi-tap I had to partially take apart and remove was for a Boeing's flight simulator that had a room of computers to run it and the ammonia chiller to cool everything. 440v battery backup with about 5 hours of run time, just enough time to have techs come in and shut system down if power is not restored.
377 volts dc was still on the "discharged" batteries, 60 - 12 volt flooded lead acid in series. I started in the very middle of battery bank and begun removing the first bus bar. I was puckered up so tight, you couldn't hammer a nail in my ass with a sledgehammer.
@@Georges3DPrinters Good on you for taking the time to record the puckerometrics. But really, you should look for a less painful option than "nail and sledgehammer." I recommend getting the Pucker-o-Meter, it'll tell you the exact force you're clenching with. it's effective measurement range goes from "Prolapse" to "Making Diamonds." It's an excellent little tool. Unfortunately it can't quite read up to "Black-Hole" pressure, though speculation has it that v2 will expand it's capabilities.
@@TheMinecraftACMan 😂😂😂😂
@@TheMinecraftACMan 🤣😂🤣😂🤣😂
im sure hes been out there several times replacing motors & allways finding low voltage.
alot of motors have probably died before you get to this point.
as Long as utility company says its all good on thier end / Transformer is ok & and a Electrician says the Panel incoming & outgoing voltage are the same / the Panel is in good shape. if your loosing motors , this is what u have to do.
thank U for those amazing videos , adding more captions language like Arabic if possible will be great ! Thanks again 🙏
I ran a huge facilities plant. Did anyone check the utility voltage inlet to the main bldg meter panel? Possible voltage drop from bad breakers or bldg disconnect switches or buss-bar contacts inside the customer's bldg wiring connections. Verify utility voltage vs. end of run up to the roof units. 5% voltage drop is too much.
Good Video & been there done that. You should allways make sure to consult with utility company first. Tell them voltage your seeing at the panel. i had a panel in a restaurant at 197-202 also and it was throwing codes in a Manitowoc indigo ice machine had a Low voltage issue too. i almost ready to put one of these on the manitowoc. utility company came out and found a transformer issue. they repaired. no problems since. its a good idea but remember those 2 transformers are going to put off some heat. if they are outdoor rated i would have mounted them outside the panel. if not maybe put a few 2" holes in ends of panel with screen & boxer fan on a Ranco etc111-000 temperature control. to see if needed drop a temperature monitoring device in the panel & download data to laptop via usb temperature monitoring stick.
Are they 1ph transformers that you connected together to get the extra leg to make them 3ph?
My chiller tandem compressor oil low cold .
Expansion valve is new emarson 50 ton system and added a accumulator but not effective
Can u help me?
👍
Interesting
ERIC,
Are you related to the famous auther, JIM MELE?
@Eric M You sure? There's some inheritance monies that didn't seem to get properly doled out. They might be looking for YOU! (But, not very hard......)
First and definitely not the last
Why not call the utility and adjust the taps on the transformer?🤔
🥃🍺🍺🍺🥃🍿🏌🏻♀️
Stay safe.
Retired (werk'n)keyboard super tech. Wear your safety glasses.
Thanks I will try some because I have the same problem
Perfect, even though slightly off balance, this will prevent current rising and motors overheating. My education only mentioned the buck boost in a lower capacity for watt motors on reach in coolers that also were 201 vac supply. Utility could not adjust incoming without a major rework on a pole many streets away.
Thanks guys at Kalos hvacr school for the tips.
Never stop learning. 👍🏼
Eric M, did you have to consult with the OEM application electrical engineer to do the retrofit?