950 KW Genset Rectifier Fuses

[rixtalbert]

Dear Engineers,

I have a client that is using a 950KW Cat to run a Rock crusher plant. The output voltage is 480 three phase.
The unit is probably 20 years old and had a $90,000 dollar rebuild about a year and a half ago!
We are running the set at near peak output and over the last year it has started blowing the rectifier fuses, type Bussman KAC 70 amps. At first we thought it was the load that may be doing it but have observed that the fuses may blow at any time! Even with no load. Bussman website states that the KAC fuse is only produced for old designs and recommends the FWP 700Volt style for new designs. The cat people have changed out the voltage regulator a few months ago but the problem still surfaces at least once a week!
Does anyone have any input on this grelim?

Thank You very Much

Rick Talbert

 

[alehman]

Intermittent short in the field wiring or winding? Has anyone meggered the field? What does Cat say about the fuse type?

You could have bought a new one for not much more than the overhaul!