[Phillipd]

We have a customer that has a new large home we did the electrical for last year. It has a 400A service and a 50kw automatic standby generator. They should have closer to 100kw but 50kw was all our suppliers had access to last fall. There are quite a few heating loads on the on the service so i imagine the 50 is working plenty hard but is keeping up during the recent outages they had.
During todays severe cold outage, the water pump didn’t run but after the power came back on so did the water. The transfer switch feeds a 400A distribution panel then branches off to 3 200A panels in the property. They have a constant pressure pump controller, we’re going to simulate an outage next week and see what’s up. My guess is during very cold weather during an outage it may not be getting sufficient propane flow and the load would be increased. That would cause frequency fluctuations and possibly the pump controller may be rejecting the source. If that is the case should we add a UPS to feed the controller and if so how big? Maybe I’m way off here just drawing straws at the moment.

 

[SWDweller]

Glaring question did the generator come on?

 

[Phillipd]

Glaring question did the generator come on?

Yes it did , whole house ran except the water pump

 

[splatz]

Is it possible the water pipe froze?

 

[Phillipd]

Is it possible the water pipe froze?

I wouldn’t say so, they said the genset ran about an hour and a half then the utility supply was restored. After the ATS switched back the water was restored.

 

[SWDweller]

I do not have a clear concept of the electrical system. If the gen started and the transfer switch operated then all should have worked. Considering the house operated.

Possibility of a breaker off?
This is not a control problem. The house had power.

Your idea about the propane and fuel is possible in very cold weather, but you said the generator ran. 50kw gensets have controls for voltage and Hz. The generator self check will cause the generator to shut down if it finds anything wrong. The generator should have a block heater on it or the very least an oil heater.
Hint it would be a great idea for the motors on the property that the generator starts and runs for at least a minute, longer would be better, before slamming it with the load. Motor loads are 6 times FLA for a few cycles.
Pump motor controller? You ask a question without the facts.
Did anyone do a start up on the controller? What are the voltage and Hz settings?

I once had a pump controller that failed intermittently. Upon my inspection of the settings it was found that the controller was set for 480v and was on a 440v electrical system. 440 is an old voltage not provided any more.
Problem solved

 

[Southeast Power]

We have a customer that has a new large home we did the electrical for last year. It has a 400A service and a 50kw automatic standby generator. They should have closer to 100kw but 50kw was all our suppliers had access to last fall. There are quite a few heating loads on the on the service so i imagine the 50 is working plenty hard but is keeping up during the recent outages they had.
During todays severe cold outage, the water pump didn’t run but after the power came back on so did the water. The transfer switch feeds a 400A distribution panel then branches off to 3 200A panels in the property. They have a constant pressure pump controller, we’re going to simulate an outage next week and see what’s up. My guess is during very cold weather during an outage it may not be getting sufficient propane flow and the load would be increased. That would cause frequency fluctuations and possibly the pump controller may be rejecting the source. If that is the case should we add a UPS to feed the controller and if so how big? Maybe I’m way off here just drawing straws at the moment.

If you believe the unit is maxed out and the HO must have additional loads, Get an additional 50kw unit and parallel them, it would be a better setup than one bigger unit or adding a smaller unit for the pump package.

 

[Phillipd]

I do not have a clear concept of the electrical system. If the gen started and the transfer switch operated then all should have worked. Considering the house operated.

Possibility of a breaker off?
This is not a control problem. The house had power.

Your idea about the propane and fuel is possible in very cold weather, but you said the generator ran. 50kw gensets have controls for voltage and Hz. The generator self check will cause the generator to shut down if it finds anything wrong. The generator should have a block heater on it or the very least an oil heater.
Hint it would be a great idea for the motors on the property that the generator starts and runs for at least a minute, longer would be better, before slamming it with the load. Motor loads are 6 times FLA for a few cycles.
Pump motor controller? You ask a question without the facts.
Did anyone do a start up on the controller? What are the voltage and Hz settings?

I once had a pump controller that failed intermittently. Upon my inspection of the settings it was found that the controller was set for 480v and was on a 440v electrical system. 440 is an old voltage not provided any more.
Problem solved

Thank you , we’ll check all that out when we’re back. The home owner claims no breakers were tripped just no water during the outage and came back on after genset shut down. We have a 12kw at home and it shut down before due to low frequency when it was very cold. Somethings not adding up.

 

[nrp3]

Was the generator in fact converted to propane, ie smaller orifice or sometimes just a programming change? Was this the one that the tank size seemed a bit small for lower temps? Do try a simulated outage to see how it does. The colder the outdoor temps the better for a reality check.

 

[MHElectric]

Does this generator have load shedding modules? Was the water pump on one of them?

 

[Phillipd]

Does this generator have load shedding modules? Was the water pump on one of them?

No load shedding , direct to the main panel then to 3 separate 200A subs.

 

[Phillipd]

Was the generator in fact converted to propane, ie smaller orifice or sometimes just a programming change? Was this the one that the tank size seemed a bit small for lower temps? Do try a simulated outage to see how it does. The colder the outdoor temps the better for a reality check.

Yes this is the one I asked about a few months ago , it was ordered as a propane fuelled unit . The supplier we ordered it through did the commissioning on it and test ran it. It was -26c this morning on the thermometer, I’m surprised it started. It does have a block heater and battery tender.

 

[Phillipd]

If you believe the unit is maxed out and the HO must have additional loads, Get an additional 50kw unit and parallel them, it would be a better setup than one bigger unit or adding a smaller unit for the pump package.

Surprisingly enough they said it ran everything well enough.

 

[nrp3]

Some of the well pump controllers convert to three phase so maybe that’s the issue, the well controller.

 

[Phillipd]

Some of the well pump controllers convert to three phase so maybe that’s the issue, the well controller.

Being constant pressure I’m “guessing” it is a frequency drive to control the pump speed

 

[nrp3]

That’s where I’m going with it.

 

[Phillipd]

That’s where I’m going with it.

The home owners are going to contact their propane provider to see if there’s any type of tank or regulator heater they can have installed also

 

[backstay]

Is the constant pressure control a Grundfos? They are a soft start unit, perfect for generators because of no startup surge. I don’t use the controller on mine, but just the pump on its own is an improvement over a normal pump. I direct all my of grid customers to Grundfos SQ well pumps.

 

[Phillipd]

Is the constant pressure control a Grundfos? They are a soft start unit, perfect for generators because of no startup surge. I don’t use the controller on mine, but just the pump on its own is an improvement over a normal pump. I direct all my of grid customers to Grundfos SQ well pumps.

I have no idea but I’ll make note when we go back

 

[SWDweller]

Your 12 kw does not have voltage or frequency controls like the 50 kw does.
I would be very interested in your 12 kw unit with frequency controls.