Transformer taps

[ranger]

Today we had a discussion regarding transformer taps.One of our crews was working at a Wal Mart store.They wer'e supposed to wire a Xerox copy machine.The machine wanted to see 230 volts/not sure if it was 3 phase or 230 plus neutral.Anyway their closest/most reasonable power source was 3 phase 208.So the machine tech set the machine to run at 208 internally.The problem was that the source kicked out 200 volts which the tech said put the machine's voltage out of tolerance.The discussion went that the input voltage needs to be measured and that it may be possible to change the transformer taps in such a way as to bring the voltage up into acceptable limits.They have a rule i guess about using buck-boost transformers.My question is this does anyone know how to use the different taps on the transformer?Even if someone could point me in the right direction to learn more about this it would be helpful to me .Thanks P.S apparantly this machine was over 100K$ no room for error!!

 

[bennie]

Re: Transformer taps

Spending this amount of money and making modifications to a power supply, the owner deserves to have it smoke.

Install the correct power equipment.

 

[dereckbc]

Re: Transformer taps

You are not providing enough information for us to offer any help. It could be as simple as too much voltage drop on the circuits between the transformer and copier. Makes a lot difference if the copier needs three phase or single phase.

If you change the taps to satisfy the copier from voltage drop, you could have too high of a voltage on other circuits on the same transformer.

Just a shot in the dark but I would guess you might want a transformer installed where the copier is being used that is properly sized for the load, or adjust the conductor size going to the copier to compensate for voltage drop.

[ June 03, 2003, 10:40 PM: Message edited by: dereckbc ]

 

[frenchelectrican]

Re: Transformer taps

i do agree with derick is that copy machine is set for single phase or triphase?? and do the copy machaine do have specal tapping conneter at the control panel where it hook up the wires ?? i have done one not too long ago with triphase copymachine and it have voltage slecter switch inside the panel board i did have one have say 208 or 230 volts and i just click on the proper voltage and it work super

merci marc

 

[ranger]

Re: Transformer taps

If you change the taps to satisfy the copier from voltage drop, you could have too high of a voltage on other circuits on the same transformer.Good point Derek.I didn't think about the volt drop issue either.Maybe the thing to do would have been to measure the voltage at the source under normal load to get a better idea of what the source voltage is.Then if it was a volt drop problem upsize the conductors.What i was really trying to do"since this was not my job"was to get some info on how to use these transformer taps.It's just for my own knowledge.I want to improve my skill level.I like these forums because people smarter than me have good advice to offer.Ranger