What could I use these transformers for

Thread Starter

quique123

Joined May 15, 2015
405
I have 2 of these...one has 3 incoming wires and the other has 4. The one in the picture has DC1E7807-CED4-4924-A7F0-537A05C529B7.jpeg

They're from ups units that have died in the past. I guess those ups units stop working mostly due to faulty batteries. Anyway, Should I save them or chuck them?
 

dendad

Joined Feb 20, 2016
4,451
Why not buy a new battery for the UPS?
Also, I have run old UPS units on car batteries for longer backup time too. If you use an external battery, just ensure it is isolated from the mains in the UPS circuitry.

As for the transformers, that would be quite useful for making a couple of power supplies. Or a battery charger.
 

Thread Starter

quique123

Joined May 15, 2015
405
Well where I live it's not easy to find these types of batteries at stores.

Add for the battery charger it would only work for charging 12V batteries which I don't really have.

Power supply would be good. I'm just have to encase it properly, huh.
 

dl324

Joined Mar 30, 2015
16,845
Well where I live it's not easy to find these types of batteries at stores.
They're easy to find where I live, but I've found that it's usually more economical to buy a new UPS. I have a 1000VA UPS with bad batteries and I kept balking at the price of the 2 replacement batteries. Then I picked up another 1000VA UPS on sale for maybe 50% more than the cost of the replacement batteries.

The display was going out on the old one anyway...
 

Thread Starter

quique123

Joined May 15, 2015
405
OK so I would need to wire these cables on the high side to a 120vac plug and the low side black and red wires to the drill?

How do I know which is live and which is neutral on the high side? I have black yellow and blue. I'd imagine black is Live and Blue is neutral but how can I be sure? What about yellow?

F3D45CCB-3D88-41CB-ADFC-F161C9D0D71C.jpeg
 

Thread Starter

quique123

Joined May 15, 2015
405
I wasn't gonna feed ac to the drill. But you made me wonder about my understanding of this issue.

From what I understand, I feed ac to the transformer high side and take dc from the transformers low side which I then connect to the drill. Oh cause the lowside will still be ac right?! I need to make dc of it.
 

dendad

Joined Feb 20, 2016
4,451
No.
A transformer outputs AC, not DC.
You may be confused as some folks call the plug pack power supplies "transformers", but that is not correct. A transformer is only part of the power supply.
Have a look at those links posted earlier.
 

shortbus

Joined Sep 30, 2009
10,045
Do you still have the rest of your UPS? What is needed should be in the circuit of it, between the transformer and the battery. But take a picture and post it before just trying it.
 
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