Scenario:
One 50 amp sub panel (single phase three wire, 240v, fed with #8 ac), fed from 200 amp service.
From what I see, it looks like an existing 8 wire was used for a kitchen reno which the previous electrician installed this panel for.
He has the refrigerator and other circs going back to the main panel, but is feeding the micro, dw, some lighting (5 high hats and maybe some LV undercabs)...from this panel.
New pavers were installed for an existing pool. The original area around the pool was concrete. To remove concrete they jack hammered etc... which broke the conduits and wiring
which fed a pool pump and pool light (one 240v pump, one 120v light) from the 200 amp service.
I was directed to feed a new pool pump (240v 9.5 amps) and a new LV pool light from the 50 amp sub panel which I did.
The owner called and said his kitchen lights dimmed for a couple of seconds which they never did before.
He had the lights on, the microwave, the dw, and the pump running.
He said all was fine until the end of the dw cycle and dw turned off and lights dimmed.. (I think the dw turning off was coincidental but...).
My only thought at this time is to check into the panel, and if the kitchen 120v micro, dw, lighting...and what ever else I may discover, is heavy on one of the phases is to split
them up alittle more between the two phases.
With the total load as it is now.... if I come up with maybe 32 amps on a single phase with all running, with vd internet calculations. it doesn't seem like there should
be a sufficient vd for these lights to dim (70 to 100 feet at the most from main panel to sub panel, then 30 feet from sub panel to each load...).
My question is, if this doesn't correct the dimming, I'm leery as to talk to this gentleman about what ever it may take to get the new pump motor to be
fed from the main 200 amp service, as I've noticed that many times in alot of homes (and other places) that occasionally when an air conditioners
kicks on, whole house and or wall/window units, fed from separate circs., lighting on separate circuits still dim.
To talk to him about re-feeding the pump from the service, then to have the lights dim anyway would not be good and a bit embarrassing.
??????......... Might shedding the loads in that sub-panel eliminate the dim?
Why do air-conditioners on separate circ's sometimes dim lighting on separate circs.?
Thanks all for any input....
Rich
One 50 amp sub panel (single phase three wire, 240v, fed with #8 ac), fed from 200 amp service.
From what I see, it looks like an existing 8 wire was used for a kitchen reno which the previous electrician installed this panel for.
He has the refrigerator and other circs going back to the main panel, but is feeding the micro, dw, some lighting (5 high hats and maybe some LV undercabs)...from this panel.
New pavers were installed for an existing pool. The original area around the pool was concrete. To remove concrete they jack hammered etc... which broke the conduits and wiring
which fed a pool pump and pool light (one 240v pump, one 120v light) from the 200 amp service.
I was directed to feed a new pool pump (240v 9.5 amps) and a new LV pool light from the 50 amp sub panel which I did.
The owner called and said his kitchen lights dimmed for a couple of seconds which they never did before.
He had the lights on, the microwave, the dw, and the pump running.
He said all was fine until the end of the dw cycle and dw turned off and lights dimmed.. (I think the dw turning off was coincidental but...).
My only thought at this time is to check into the panel, and if the kitchen 120v micro, dw, lighting...and what ever else I may discover, is heavy on one of the phases is to split
them up alittle more between the two phases.
With the total load as it is now.... if I come up with maybe 32 amps on a single phase with all running, with vd internet calculations. it doesn't seem like there should
be a sufficient vd for these lights to dim (70 to 100 feet at the most from main panel to sub panel, then 30 feet from sub panel to each load...).
My question is, if this doesn't correct the dimming, I'm leery as to talk to this gentleman about what ever it may take to get the new pump motor to be
fed from the main 200 amp service, as I've noticed that many times in alot of homes (and other places) that occasionally when an air conditioners
kicks on, whole house and or wall/window units, fed from separate circs., lighting on separate circuits still dim.
To talk to him about re-feeding the pump from the service, then to have the lights dim anyway would not be good and a bit embarrassing.
??????......... Might shedding the loads in that sub-panel eliminate the dim?
Why do air-conditioners on separate circ's sometimes dim lighting on separate circs.?
Thanks all for any input....
Rich
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