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cajundood's avatar
cajundood
Explorer
Oct 30, 2017

Question about using run/start capacitors

This is for any electricians versed in the use of load and run capacitors to help with ac surges on the genny or the inverter.

I am in the middle of a teardrop build and I am
trying to get away with as small/light of a generator as possible. I ordered a 1000w sportsman inverter generator and I also have a 1000w inverter unit which will run off of 2 car batteries.
I will be running a small dorm refrigerator as well as a 5k btu ac unit.
Now....I havent tested it yet but i'm sure the surge when starting the ac unit could cause the inverter or the generator to fault out.
I noticed some yootoob videos that suggest adding a hard start capacitor that will help out with the surge.
I ordered one made by supco but am unsure on how it is wired into the system. I've also seen where some folks add a delay box on the fan so that
the compressor starts first then the lower draw fan starts after about 15 seconds. :roll:

If any of you electricians out there can enlighten me on this, it'd be most appreciated.
  • $300 for a soft start???? :E Got to be a better and cheaper way. perhaps a larger capacitor??
    I hooked up my kill a watt meter to the 5k ac and plugged it in.
    the readings i got were as follows.....

    fan only
    startup=112w
    running=66w


    fan + compressor
    startup=647w
    running=350w
  • A 1000W gen probably doesn't have the surge current needed to start even a 5K AC unit. A cap can only do so much.
    What is the wattage rating of the AC?
  • You're wasting your time ... not only are you asking an awful lot of just a 1000 watt inverter and 1000 watt genset but at the very least you'd want to equip the A/C with a Micro-Air Easy Start Soft Starter Kit which will do a far better job of controlling start up surge than will a hard start capacitor.