diy solar

diy solar

Inverter Kicking Off

To assist/try to get back in track...

Have you verified your panels and charge controller are working?
I think the most important thing is going to be measuring DV voltage and current when the issue presents.

I'd recommend more solar in general.
200 watts (for maybe 5 sun hours) is going to have a tough time running a 70 watt fridge 24/7 depending on your fridge duty cycle.
I don't know if it will be the cause of what you're seeing now, but the gut feeling says you don't have enough solar to recharge the battery after a night of running the fridge.

You might be hitting the 100 amp DC limit of the battery, but that's cutting it close.
 
400bird said:
To assist/try to get back in track...

Have you verified your panels and charge controller are working?
I think the most important thing is going to be measuring DV voltage and current when the issue presents.

I'd recommend more solar in general.
200 watts (for maybe 5 sun hours) is going to have a tough time running a 70 watt fridge 24/7 depending on your fridge duty cycle.
I don't know if it will be the cause of what you're seeing now, but the gut feeling says you don't have enough solar to recharge the battery after a night of running the fridge.

You might be hitting the 100 amp DC limit of the battery, but that's cutting it close.
Click to expand...
my panels and solar seem to be working, checked voltage at controller inputs and inverter inputs & the remote display shows battery full after a day of sunlight. I've never run the fridge for more than a couple hours as it cuts off even in the night after a full day of charge.

I'm running just a laptop charger, a string of lights and another device charger now, which all add up to 70 watts. If it was the fridge, it would've kicked off by now based on what I've observed. So wondering if the freezer-to-fridge presents some kind of issue for the system. Maybe it registers as if its running the full fridge wattage even though it shows a periodic 70 watts for the conversion..?

I know I can measure the DC voltage at the inverter inputs with a multimeter when the issue presents but not sure how I would measure current
 
Do your LEDs and laptop draw 70 watts or fridge/freezer thing?
What size is this freezer? 70 watts seems pretty low for most freezers.
What are you using to get these wattage readings?

Measure DC amps with a clamp meter. Something with an in-rush or peak current setting would be best.

I think this fits the bill:

Edit: When you say the battery is getting fully charged on the remote display. Is that the charge controller's remote display?
Did you get an SOK battery with BMS?
 
Last edited:
400bird said:
Do your LEDs and laptop draw 70 watts or fridge/freezer thing?
What size is this freezer? 70 watts seems pretty low for most freezers.
What are you using to get these wattage readings?

Measure DC amps with a clamp meter. Something with an in-rush or peak current setting would be best.

I think this fits the bill:

Edit: When you say the battery is getting fully charged on the remote display. Is that the charge controller's remote display?
Did you get an SOK battery with BMS?
Click to expand...
So everything I'm running now adds up to 70 watts, not measuring, just based on the ratings on the chargers and the string lights added together. I just find it interesting that this arrangement doesn't cause an issue but the fridge by itself does.

The fridge is an upright "Hanai" freezer converted into a fridge with a temperature bypass sensor, so its set to run at fridge temp. I just bought a kill-a-watt device (https://www.amazon.com/dp/B01D1YA8G2?psc=1&ref=ppx_yo2ov_dt_b_product_details) to read the fridge watt since it won't be accurate to the rating as a freezer. It hits 70 watts at most and rarely kicks on the compressor so its usually reading 0. Maybe this reader isn't accurate..

Ive just been using an analog multimeter to check voltage. Clamp meter definitely looks like it could be useful for diagnosis. Thanks for pointing me to that.
 
Screenshot 2022-04-30 at 08.31.45.png
This is our inverter's power graph. When the fridge starts there is a 776W spike, and 100W constant until the compressor stops. The freezer is the similar with only 180W spike and 75W until the compressor stops. The fridge is a full size household one and the freezer is an under counter one.
 
Gabrielle said:
So everything I'm running now adds up to 70 watts, not measuring, just based on the ratings on the chargers and the string lights added together. I just find it interesting that this arrangement doesn't cause an issue but the fridge by itself does.

The fridge is an upright "Hanai" freezer converted into a fridge with a temperature bypass sensor, so its set to run at fridge temp. I just bought a kill-a-watt device (https://www.amazon.com/dp/B01D1YA8G2?psc=1&ref=ppx_yo2ov_dt_b_product_details) to read the fridge watt since it won't be accurate to the rating as a freezer. It hits 70 watts at most and rarely kicks on the compressor so its usually reading 0. Maybe this reader isn't accurate..

Ive just been using an analog multimeter to check voltage. Clamp meter definitely looks like it could be useful for diagnosis. Thanks for pointing me to that.
Click to expand...
Your not exceeding the capacity of your system and your Kill a Watt will show that but the connections might be an issue.
 
My manual states for refrigeration the inverter should be sized to three times the rated watts of the device. The rated watts, from the data plate, not the "measured" watts.
 
Zil said:
My manual states for refrigeration the inverter should be sized to three times the rated watts of the device. The rated watts, from the data plate, not the "measured" watts.
Click to expand...
Perhaps Her manual is different? We always used 3 to 4 times the RLA for motor sizing just for starting not running.
 
Yes. There are quality and there are inexpensive inverters.

Note; The fridge has a motor driving a compressor. It doesn't matter what the temperature is set in the fridge. The motor demands the watts that are listed on the motor data tag. Plus the surge on startup.
 
Zil said:
Yes. There are quality and there are inexpensive inverters.

Note; The fridge has a motor driving a compressor. It doesn't matter what the temperature is set in the fridge. The motor demands the watts that are listed on the motor data tag. Plus the surge on startup.
Click to expand...
Thats not how it works, the compressor only runs on demand of the thermostat... not all the time if it has good insulation it runs less often. . The start up wattage for any motor is higher than the running. You size the wires for the RLA, the inverter should have enough surge capacity to start the motor.
 
That is how it works.

The fridge should run less frequently (compared to a freezer) but when running (or starting) it will require the same energy.

To clarify, yes the thermostat controls when the compr runs. But, I don't think that was relevant to the statement Zil made.
 
Zil said:
My manual states for refrigeration the inverter should be sized to three times the rated watts of the device. The rated watts, from the data plate, not the "measured" watts.
Click to expand...
Start Up Amps/Watts = 6.3 / 724.5. Running Amps/Watts = 1.5 / 172.5 is the rated.

So you're saying it needs three times the start up?

If that was the case it seems like the inverter would have trouble on start up, not after a few hours of running when its already done the major cooling work
 
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fega72 said:
View attachment 93102
This is our inverter's power graph. When the fridge starts there is a 776W spike, and 100W constant until the compressor stops. The freezer is the similar with only 180W spike and 75W until the compressor stops. The fridge is a full size household one and the freezer is an under counter one.
Click to expand...
Zil said:
Yes. There are quality and there are inexpensive inverters.

Note; The fridge has a motor driving a compressor. It doesn't matter what the temperature is set in the fridge. The motor demands the watts that are listed on the motor data tag. Plus the surge on startup.
Click to expand...
This doesn't really make sense to me. But I suppose there's a lot I don't know about these things. The whole purpose of the freezer to fridge was to have a super efficient fridge for solar use, but you're saying the motor will need the same watts regardless? Even if it hardly has to kick on the compressor? And the kill-a-watt meter is useless in this case?

I'm not just setting the temperature on the appliance, but setting the temperature controller that is plugged into the appliance before in between it and the inverter:

Which I thought would alter the wattage needs of the appliance but I guess only over time judging based on the consensus of everyone here. Makes sense to me now.
 
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Gabrielle said:
This doesn't really make sense to me. But I suppose there's a lot I don't know about these things. The whole purpose of the freezer to fridge was to have a super efficient fridge for solar use, but you're saying the motor will need the same watts regardless? Even if it hardly has to kick on the compressor? And the kill-a-watt meter is useless in this case?

I'm not just setting the temperature on the appliance, but setting the temperature controller that is plugged into the appliance before in between it and the inverter:

Which I thought would alter the wattage needs of the appliance but I guess only over time judging based on the consensus of everyone here. Makes sense to me now.
Click to expand...
Your watt meter is showing the actual draw of the unit. The nameplate is only a guideline. The watt meter shows the actual work the compressor is doing, when the door has been open for a while or the ambient temperature is higher the watt meter will show more. Its possible the Inverter is getting overloaded at times IF both units are running or try to start at the same time. Your making good progress troubleshooting. I wish I had someone like you when I was running the service department crew.
 
Update: I replaced the mega fuse with MRBF terminal fuse at the battery, sanded and cleaned connections and reordered the stacked wires so that the inverter is the first one on the fuse. and its working!! It's hour 3 and everything running smoothly. Fridge is cold, I'm charging another device also, all good. Inverter always turned off by hour 2 before.

Thank you to all who provided insight, I really appreciate it. Feels so good to finally have it functioning.
 
Gabrielle said:
terminal fuse at the battery, sanded and cleaned connections and reordered the stacked wires so that the inverter is the first one on the fuse. and its working!! It's hour 3 and everything running smoothly. Fridge is cold, I'm charging another device also, all good. Inverter always turned off by hour 2 before.
Click to expand...
Give us an update in a few days. I think it sounds like you have it but that was a curious thing.

Maybe you posted it but a link to the undercounter freezer? How many CF? Does it have a separated coil to bleed heat, or does it radiate heat from the case? Is it “frost free?”
I’m super intrigued by that - although the wattage is a tad high it should run less often (than a fridge) in theory mitigation overall consumption.
 
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