Motor starting surge on a generator?

[zbang]

Sorry folks, it was a busy few days (and I haven't read all of the replies).

Lessee...
Each side of the machine as a compressor at 19 RLA and an auger motor at 9 FLA, they auger only runs when the compressor is also running. How this works on a 50 amp breaker is left to the student, probably because nothing runs for more than a few minutes/seconds at a time. Without other checks, each side of the machine should probably have it's own 50 amp circuit but that's not how the trailer is wired.. I'm definitely going to run those down the install instructions even though we probably won't see the machine for another year. The machine is UL listed.

Operating voltage is around 210-211, connected with 50' of 6/4 SO into an outdoor distro panel and 50' of 1g(?) to the gen. No VFDs or anything fancy involved. Without a decent logger handy we couldn't catch the sag/surge.

(ETA- each side MOP 45 amp, MCA 33.3 amp)

Once we swapped in 150kva gen, that barely noticed the motors coming on and so no lights flickering - that was good enough for the weekend.

I'll post more once I've run down the machine instructions and had a few more hours of sleep, a week of 5-6 hours a night does me no favors.

 

[ptonsparky]

Sorry folks, it was a busy few days (and I haven't read all of the replies).

Lessee...
Each side of the machine as a compressor at 19 RLA and an auger motor at 9 FLA, they auger only runs when the compressor is also running. How this works on a 50 amp breaker is left to the student, probably because nothing runs for more than a few minutes/seconds at a time. Without other checks, each side of the machine should probably have it's own 50 amp circuit but that's not how the trailer is wired.. I'm definitely going to run those down the install instructions even though we probably won't see the machine for another year. The machine is UL listed.

Operating voltage is around 210-211, connected with 50' of 6/4 SO into an outdoor distro panel and 50' of 1g(?) to the gen. No VFDs or anything fancy involved. Without a decent logger handy we couldn't catch the sag/surge.

(ETA- each side MOP 45 amp, MCA 33.3 amp)

Once we swapped in 150kva gen, that barely noticed the motors coming on and so no lights flickering - that was good enough for the weekend.

I'll post more once I've run down the machine instructions and had a few more hours of sleep, a week of 5-6 hours a night does me no favors.

“Event” kinda flagged you didn’t have time to do much other than react. Besides, it kept us busy.

 

[Joethemechanic]

Caterpillar 3516

Trenton NJ has two of them running shaft driven centrifugal pumps at the sewer plant. They have a combined sanatary and storm water system, and during hard rains there is too much water for the plant to handle. So the water comes over the top of a weir and flows into a giant underground chamber with the pumps in it and they pump it up about 25 feet and it flows into a storage lagoon. When those things start up they move a lot of water

 

[zbang]

Interesting comments, everyone. One thing to keep in mind is that unlike a permanent installation, the mission here was to make the apparent problem lesson or appear to vanish, not to fix the underlying cause; sometimes that's running a second feed to a vendor, sometimes it's swapping for a vastly-oversized generator . That took some coordinated effort, but we had only a 15 minute outage and that included moving both generators which were over a half mile by road apart.

Good call on the governor/controller, the controller is Deep Sea, the governor is probably a Leroy Somers D350 (which I now have the manual for, don't feel like springing $250+ for the NFC comm dongle to talk to it but it looks like there's a lot of interesting data inside).