A/C off of 20 amp service?
Has anyone ever heard of a single a/c unit not being able to start and run on a 20amp shore power circuit? We bought a new coach and the dealer says don't run a/c unless connected to a 30 amp servic...
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Hi CA Traveler,
I should have qualified my reply by stating I was at a 30 amp pedestal.
There is no "magic" about an autoformer--it can not create "extra" watts and will consume some watts.
I have been at more than one 50 amp location where voltage was an issue when running "heavy" inductive loads.
The "real" math for the Sola Basic autoformer on a 20 amp source at 105 volts would be:
105 x 20 = 2100 watts
2100 X 96% = 2016 watts (4% overhead from SB)
Boost would be to 115 volts on a 105 volt supply
2016 / 115 = 17.53 amps output to the RV from SB
17.53 X 80% =~ 14 amps for safe continuous duty.
Numbers were rounded down.
What I like most about the Sola Basic is how fast it switches in when the start up surge "hits" the supply from the roof air. It comes on in time to help with that--before I hear the sound of the roof air starting.
I think I'm seeing less wattage "creep" (i.e. roof air drawing more and more watts) when using the autoformer, but the cooling season is over now--so I'll have to do a "back yard" experiment in the future.
I should have qualified my reply by stating I was at a 30 amp pedestal.
There is no "magic" about an autoformer--it can not create "extra" watts and will consume some watts.
I have been at more than one 50 amp location where voltage was an issue when running "heavy" inductive loads.
The "real" math for the Sola Basic autoformer on a 20 amp source at 105 volts would be:
105 x 20 = 2100 watts
2100 X 96% = 2016 watts (4% overhead from SB)
Boost would be to 115 volts on a 105 volt supply
2016 / 115 = 17.53 amps output to the RV from SB
17.53 X 80% =~ 14 amps for safe continuous duty.
Numbers were rounded down.
What I like most about the Sola Basic is how fast it switches in when the start up surge "hits" the supply from the roof air. It comes on in time to help with that--before I hear the sound of the roof air starting.
I think I'm seeing less wattage "creep" (i.e. roof air drawing more and more watts) when using the autoformer, but the cooling season is over now--so I'll have to do a "back yard" experiment in the future.
