installing a 150 MFD start capacitor for chest freezer

What is the brand/model number of freezer? There are a lot of different configurations out there.

-Bill

Best I could do was find a simple electrical diagram:

Service Manual - Premium Appliances

Many refrigerators and freezers use an "integrated" start relay+capacitor and it may not be easy to change the capacitor for a different value.

In general, refrigerator/freezers are not really designed to operate on a limited power output off grid power system. They are design assuming you have utility power that can supply very high starting current.

Assuming you have a starting capacitor on this refrigerator (from the manual, apparently not all of them do)--You may be able to remove the existing capacitor and try a smaller value. Which may, or may not help.

Two other things I would try... First, look at your DC battery to inverter connections. You need very heavy wire/cabling, kept short so that you have very little voltage drop from the battery to the inverter. Also, the battery bank needs to be large enough (and in good condition) to supply enough surge current. For a 12 volt battery bank (guessing), a 1,400 watt inverter that can supply 2x surge power for a few seconds, the DC current would be:

• 2,800 Watts * 1/0.85 AC inverter eff * 1/10.5 volts battery cutoff = 314 Amps worst case surge

And you would need to have less than ~1.0 volts drop (11.5 volts minimum battery voltage, 1 volt drop, for 10.5 volts minimum at the inverter).

If you do not have enough available power/current on the DC side of the inverter, it will cutoff/shutdown during compressor starting. A 1,400 Watt AC inverter should be enough to start that freezer (all things being equal).

And the minimum size (AH) battery bank would be roughly 2.5x the starting current: Assuming 12 volt battery bank (24 volt would be 1/2 the current & AH capacity):

• 314 amps * 2.5 battery capacity factor = 785 AH @ 12 volt battery bank

And lastly, a trick that sometimes work. The freezer compressor/starting capacitor is designed to start in worst case power conditions (low line voltage, poor wiring, etc.). Get a long extension cord (15 to 30 meters) and plug the freezer into the inverter using the extension cord. In some cases, the extra resistance of the cord is enough to reduce the starting current--Preventing the inverter from shutting down, but still enough current for the compressor to start.

-Bill