Inverter for PowerPack Recommendation?

BigWink

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I built a power bank with the below config. I am looking for an inverter that I can use in the event of a power outage to run the refrigerator for a few hours. The fridge does spike when the compressor engages but I don't have a way to measure how much. The spec on it requires 8.5amps, no other power consumption info on it. Any recommendations on an inverter brand and spec would be appreciated.

7s10p
LG M29s 10A 2850 mAh
Daly 100A BMS
 
What brand and model is the refrigerator?
The manufactor proably has the data online. Especially if it is energy star rated.
later floyd
 
I would guess that 8.5a * 120v = 1020watts is the surge/max since my full-size US refrigerators run at 250w. But I agree with @floydR - you should be able to pin this down by searching out specs.,

A 'high frequency' inverter will be cheaper (and lighter) - but they don't have any surge capability and typically don't do 100% of advertised wattage so you would get something 2x or even 3x the size you need. An example of an OK/cheaper inverter is this Reliable 24v@2000w - https://www.amazon.com/WZRELB-Relia...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

A 'low frequency' inverter (has a heavy transformer) will be more expensive but they can handle surge very well. Here's an example of a middle-higher-end/more-expensive AIMS 2000w @ 24v - https://theinverterstore.com/product/2000-watt-pure-sine-inverter-charger-3/ This AIMS can also charge (using grid power) to keep your battery charged.

If you doing this more as a UPS you could even just go with a refurbished APC 1500 UPS such as this - https://www.ebay.com/itm/APC-Smart-...536180?hash=item3fe67794b4:g:Yr8AAOSwyoNf2lta I have several of these with 7s7p 18650 batteries - the point being that 7s works pretty well with these. A 7s10p can be crammed inside - but the battery doesn't strictly need to be inside so you could do a larger one in the future.

FYI - I'm not pushing either of these brands, they're just ones that I've used personally and have experience with :)
 
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I would guess that 8.5a * 120v = 1020watts is the surge/max since my full-size US refrigerators run at 250w. But I agree with @floydR - you should be able to pin this down by searching out specs.,

A 'high frequency' inverter will be cheaper (and lighter) - but they don't have any surge capability and typically don't do 100% of advertised wattage so you would get something 2x or even 3x the size you need. An example of an OK/cheaper inverter is this Reliable 24v@2000w - https://www.amazon.com/WZRELB-Relia...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

A 'low frequency' inverter (has a heavy transformer) will be more expensive but they can handle surge very well. Here's an example of a middle-higher-end/more-expensive AIMS 2000w @ 24v - https://theinverterstore.com/product/2000-watt-pure-sine-inverter-charger-3/ This AIMS can also charge (using grid power) to keep your battery charged.

If you doing this more as a UPS you could even just go with a refurbished APC 1500 UPS such as this - https://www.ebay.com/itm/APC-Smart-...536180?hash=item3fe67794b4:g:Yr8AAOSwyoNf2lta I have several of these with 7s7p 18650 batteries - the point being that 7s works pretty well with these. A 7s10p can be crammed inside - but the battery doesn't strictly need to be inside so you could do a larger one in the future.

FYI - I'm not pushing either of these brands, they're just ones that I've used personally and have experience with :)
I have the APC option here but they never fully charge to the capacity of a 7s lion battery. They stay with the range of the legacy lead-acid.
 
I have the APC option here but they never fully charge to the capacity of a 7s lion battery. They stay with the range of the legacy lead-acid.
Yes - 27.5v which is 3.94v/cell is where my APCs settle.. This is not so bad SOC wise its about 75% and since you don't typically charge beyond 4.15v (97%?) max or 4.10v (91%?) for longer life anyway you only loose 15-20% SOC. In a 7s10p you can make that up that 20% by going up to 7s12p - extra 14 cells ($14?). APC 1500 is cheap compared to inverters, has gentle charging, you can add a network card for monitor and AT 3.94v/cell is that is 'easy' on the cells and they should last a loooong time. Again - not pushing anything, just chatting. The only correct decision here is what *you* decide for your situation :)

Here's my bench/test APC 1500 with 7s7p - you can see the standard APC 27.56v on the Chargery BMS display. The APC 1500 charges at 3a/80w range.
1610661779254.png
 
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You can as well go with a cheap high frequency inverter and use a soft start device to handle the surge. If it is just for the occasional emergency power outage....
 
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