Split Phase Balancing

stmar
stmar Solar Expert Posts: 370 ✭✭✭
I understand the theory behind split phase balancing. In the real world power consumption is not always the same so what factors do you look at when moving breakers around? For me, especially in the winter, the pellet stove is on a lot while the central heat only comes on in the morning usually. The wife has her morning routine with hair dryer and curling iron, mircrowave and toaster would not be in play at the same time. Washer and gas dryer would not coincide with the bathroom or kitchen appliances. What I am trying to get at is like when the washer and dryer (same circuit) are on not much else is being used, except maybe the pellet stove in the winter, so this would not be in balance. Am I overthinking it and going down the rabbit hole? Been known to do that.

Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Load balancing is a tricky subject, in an industrial situation where loads are consistent throughout the day, ventilation fans, pumps and so forth, a data logger would be employed to sample over a week trends which occur, with that information balancing between phases would employed. On a split phase system with intermittent loads, such as a hiring dryer, microwave or toaster for example, it's almost impossible to achieve perfect balance. The best way to achieve ballance, in my opinion would be to not use the split but rather use a transformer over the 240V to achieve the 120V, that way the 120V loads would always be in ballance, but then again, is it really worth the bother, that would depend on grid support and the ability of the inverter to deal with imbalance in the first place.
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  • stmar
    stmar Solar Expert Posts: 370 ✭✭✭
    Grid support is not bad, few hours long outages per year. I am in the process of installing a Schneider Conext SW4024 so I guess I will balance as near as possible for my usage and see how the new inverter works.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    stmar said:
    Grid support is not bad, few hours long outages per year. I am in the process of installing a Schneider Conext SW4024 so I guess I will balance as near as possible for my usage and see how the new inverter works.
    So, the SW in grid mode, does not handle load imbalance well at all, so in this case, to get better electricity sales, lower losses, a auto-transformer may be the best idea.    I'm not the SW expert, but I think this is the gist of what I've gathered.
    If you are off-grid, and the inverter is not faulting from imbalance, I'd not bother with a transformer.
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