voltage regulator problem

Hello snpsea

You do not advise your location or Country (If you do this in your "Profile", then it auto-updates to all Posts)

You risk invalidating any warranty on the machine, and probable burnout.

You don't state what the Fan motors are: 1 phase or 3 phase, and how many, what size each fan motor is.

For technical assistance, refer: http://www.cat.com/cda/components/fullArticleNoNav?m=76100&x=7&id=285577.

Trust them, they are the Makers, and they will advise you correctly.

Advise your progress here, with

Kind Regards....

thanks for yr input

however i checked with Haiti people

it seems it is a kohler 70 kva 1973-1980 model. working perfectly and smoothly at 220volts

when technician get it to 410 it shorts out the fuse on the main board as well as voltage regulator.

any suggestions aside from them getting a newer model which is out of the question for now.?

thanks

peter

hi

is it desigend to run at 450 460 v ?

can u give some more details of your problem ?

regards

divyesh patel

Hello again, snpsea

Your figures just don't seem to add up.

The voltages you state appear to be differing from the normal.

Normal voltages of a 3 phase unit are:

• 220Volts 1 phase to neutral = 380Volts 3 phase
• 230Volts 1 phase to neutral = 400 Volts 3 phase
• 240Volts 1 phase to neutral = 440Volts 3 phase

And so on.

You haven't advised re the fan motors, as I asked earlier.

So it is not a Cat unit, but a Kohler.

Refer to: http://www.kohlerpower.com/index.htm

Ask them for help, they are the makers, and will be delighted to assist you.

Advise progress, with

Kind Regards....

thanks for yr input. very much appreciated.

will call Kohler.

peter

Yes cat. people are very good, they disassembled the radiator to find a bad piston on a 3508 900 kw. generator

snpsea; did you reconnect or rewire the generator for 440/480, ? if so hook the

vr across the 220/240 part of the generator winding.. perry

Have no experience with such, hope this helps;

1990 Cat 70KVA, geared for 220 3 Phase; L-L volts is approx. 381.05V, 183.73A.

New Fan is rated for 480V; what is the regulative transformer ration ? Assume you are regulating voltage at 381.05V plus-minus 10% or 5%. This is not sufficient to supply your fan at 480V. AS the fans are design rated for 480V, approx. 277.13V 3 phase.

For a special case regulator; try check electrical markets for a step up transformer to bring 381.05V to 480V. This will work well if you find one. Regulators do not step up or down voltage as in Stepping Transformers, but maintain a set nearly constant voltage output from it to load by plus-minus increments per it's ratio to the energy source.

Cancell 450V out, they may run at 460V; Where your 3 phase volts will be 265.58, 11.55V less from rated 3 phase volts. Ensure volatge drop on cable is at least below (approx. 12V Australian Standard) the standard of your country, and use appropriate cable size ( good energy transmssion, reduce heat losses). I can not say there will be on going problem, its your decision to do a test trail with necessary electrial safety taken into account, and measure the electrical parameters.

Best solution; is to use a fan that will work on max. volts of 220V 3 phase, approx 381.05V L-L,to avoid such problems. This will be truely compatible to your 1990 Cat 70KVA.

ron,

thank you or yr input

i checked with the party who is in Haiti actually. I am just helping him out here

i found out is it a Kohler generator and i have called corporate headquarters.

what is annoying is that the Kohler ep in that country cant figure it out it seems, 10 days have gone by and it is still not operating and it is geared for 480Volts according to its manual and serial number.

go figure.

Lord, you are far away !!

tks

peter

thanks <ron

problem solved after calling manufacturer. schematic was forwarded and guesswork taken out and all is well.

thanks again for yr input

peter

In order to accomplish what you need to do, the Kohler unit has to be dual voltage. The first task is to change the winding configuration at the generator from 220V (line t line) to 480V(line to line). The generator should have the proper configuration posted on the inside of one of the covers. In the control cabinet, there should be a small control transformer. The transformer should have multiple taps and these would require changing as well.

If the unit is not dual voltage, I do not know if you can accomplish what you want to do. It sounds like you were trying to overdrive the field from the previous posts. This would explain the fuse problem you experienced.

I assume you are changing it to a high wye configuration. if you have a 12 lead gen you can simply move the sensing leads to sense at 277 (1/2 way point normally T7 T9) and use the same regulator.

Some gen-sets are build to run 220 or 480. This usually done be a wiring change and not a regulator change.

Check your wiring diagram and it will tell you which wire to move and where to move them.

The gen-set will deliver 480 at half the amps that it has at 220.

Normally you will disconnect the parallel wires and then connect them in series. Do not do this without the correct wiring diagram.

thanks

have received the schematic this morning and proceeding along those lines

regards

peter

hi sir:

is your generator 220v 3phase 0r 380v 3phase?

if it is 220v you can not get 460v! because it is 220v.

if it is 380v and the equipment is 480v 60hz, you need to increase the speed to get 60hz and adjust the voltage to be 480v.

most of cat generators has 230v-480v output, maybe you need to change the connection of the stater leads, if they are marked connect like this to get 480v: 4 to 7, 5 to 8, 6 to 9. 1 will be line 1, 2 will be line 2, 3 will be line 3.

if your regulator supply voltage is 480v, then you supply it from line1,2,3.

if it is 220v then supply it from 4-7, 5-8, 6-9.

T0 is the neutral, it should be connected to 10-11-12.

please reply?

electric! try it one time only. any way, u will not be there to try it after?