caterpillar voltage control problems

[loopierxp]

Hi everyone! I am new here and having some problems. I have been working on a caterpillar sr4 99kw generator. It was equipped with a vr3 auto regulator which went out. I replaced the vr3 with a vr6 and the generator works fine in auto but when I switch to manual it pops the 12 amp fuse on the front of the caterpillar 7c-2700 manual voltage controller. When switched back to auto it would then spike over 600 volts (480 volt system) so I shut the regulator off. Thinking it was a bad manual controller I replaced the 7c-2700 with a basler mvc300 and encountered the same problems. My sensing voltages are rock solid at 240vac and my excitation voltage sits at approximately 10.8-11vdc with about a 2.5 amp draw. I am stumped with this one. Any help would be greatly appreciated. Thanks in advance.

 

[catserveng]

You need to use the Basler MVC112 Manujal Voltage Control, use the Basler AVC 63-12 manual, publication number 9337200991F for reference.

Here is the link to the correct manual voltage control module,

http://www.basler.com/downloads/1792_990_RevD.pdf

As I remember (sorry, been awhile since doing this last) the difference is a freewheeling diode in the field circuit that prevents the VR6 from seeing an open field condition during switchover, also some additional circuitry to better manage power for excitation when using a static excited generator, at 99 kW I'm assuming you do not have a PM, correct?

Anyway, hope that helps,

Mike L.

 

[loopierxp]

Thats correct. No permanent magnet. I will look into trying the mvc112. Thanks for the input.