UPS Transformer 1000VA

[LewisTodd]

Hi all, I've recently acquired a very nice Uninterrupted Power supply transformer which is out of a APC 1000, i really want to know more about it before wiring it up to mains power first i need to know if its designed to run on 240v 50Hz and what sort of output it will produce last thing i want to do is wire it up turn it on and it throws around arcs like a MOT lol it has i believe 4 inputs (white, black, blue, yellow) if im not mistaken the black and white are the primary inputs? and on the output there is two more black and white wires. On the top it has stamped 430-1215 Class 180(H) R333H LEI-4 E154515 3L13. If anyone could share some knowledge about these with me it would be greatly appreciated!




Transformer by Lewis Todd2011, on Flickr

 

[Resqueline]

You'll need to verify the mains windings by ohming out all the thin wires. There could be two 120V windings. Phasing them correctly for 240V is another matter though.
It's likely to produce 9.5V or 19V on the thick wires depending on whether it used 12V or 24V batteries.

 

[LewisTodd]

They have about 2.5 Ohms between the wires and It used 2 x 12v cell's. How would i go about splitting 240 volts between the two windings and then getting them into phase? Cheers!

 

[Resqueline]

2.5 ohms between what wires? It's probably more about getting it back to 240V from the two separate 120V windings. Or do you want to run it on 120V?

 

[Robbo]

Hi Lewis,

I just ripped one of those apart, and tested the transformer. Mine is marked exactly like your, even though it comes from a 1500 model.

The transformer looks to be used to step 24V switched, from the battery, up to 240, and possible used in reverse to step 240 down to 24V. Or alternatively 120V to 12V

In my case I tested the transformer with a small Variac, and found that it has a 10:1 turns ratio. (If I applied 10V AC across the white/blue thin wires, I get 1V out of the thick black/white wires).

I stepped the Variac to produce 120V AC and got 12.2V.

The yellow and black wires are alternative voltages taps to allow the UPS to adjust for different mains voltage supplies - in the 1500 model they were connected to relays that could switch them in/out.

For my purposes the thin white/yellow combo was perfect, as I get 13.8V from the secondary, with 120V in - producing at least 20 amps

hope this helps,.
Robbo

 

[Resqueline]

Very useful information Robbo, thanks!
You should be able to pull around 60 Amps from that one (being made for 240V) btw..
So there's not two separate windings but one contiguous with three taps?
It seems the white is common, with 9.8:1 for the blue, and 8.7:1 for the yellow. What is the ratio for the black? (Or the voltages on the others with 120V on the yellow?)

 

[Robbo]

Very useful information Robbo, thanks!
You should be able to pull around 60 Amps from that one (being made for 240V) btw..
So there's not two separate windings but one contiguous with three taps?
It seems the white is common, with 9.8:1 for the blue, and 8.7:1 for the yellow. What is the ratio for the black? (Or the voltages on the others with 120V on the yellow?)

This is what I think the transformer windings are: (ASCII art)

'W ------------3 ||
'. . . . . . . 3 ||
'. . . . . . . 3 || C------ WHITE
'B ------------3 || C------ BLACK
'Y ------------3 ||
'U ------------3 ||


where W is the thin white wire, B is the thin black wire, Y yellow, U blue

W - B is for 110V
W - Y is for 120V
W - U is for 130V

giving 13.8V rms-AC at 30+ amps - more if you're ok with the transformer getting warm