Hi Scotty. To be fair to Cat; Their software considers a default voltage dip when starting motors.
The default voltage dip is reasonable but conservative.
Many customers, especially for standby sets, are willing to accept the greater voltage dip of a smaller cheaper set.
I haven't looked at Cat software for years now. I think that you may be able to change the default voltage dip.
On aspect of a generator set is what happens when it is hit with an overload.
If the real portion of the overload is greater than the capacity of the prime mover, the set will slow down.
Once the set drops more than 3 Hz, (57 Hz or 47 Hz). the UFRO (Under Frequency Roll Off) feature of the AVR (Automatic Voltage Regulator) becomes active and drops the voltage to maintain the Volts per Hertz ratio.
This may be thought of as the poor mans version of a VFD.
Before UFRO was a feature, it was common for a mechanic to forget to turn off the AVR when doing adjustments with the set at an idle.
UFRO now has two advantages.
1> It avoids AVR burn-out at slow speeds.
2> It acts to shed the load by reducing the voltage in proportion to a frequency reduction to allow the set to better recover from momentary overloads such as motor starting.
With loads such as this, I recommend, when site conditions permit, that the transformer and motor be connected and that then the set be started. This will bring the transformer and the motor up with a good Volts per Hertz ration and avoid almost all of any starting surges.
You may have to tweak the generator controls and you may have to power an AVR with a UPS (Uninterruptible Power Supply) to ensure voltage output at low RPMs.
Bill
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"Why not the best?"
Jimmy Carter