question

glstromeyer avatar image
glstromeyer asked

BatteryProtect does not allow 12v refrigerator to start

We have a BP-65 connected to two 110 Ah batteries driving some lights, a vhf radio and a 12v refrigerator. The protector does not allow the fridge to run. I imagine the starting current of the compressor is kicking in the protection... Should I try to program the protector to a lower disconnect voltage or? The fridge also has a protection circuit which shuts off the fridge when the voltage drops low, but it then cycles back on and continuously when the voltage source rises again and then falls.

Battery Protect
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5 Answers
glstromeyer avatar image
glstromeyer answered ·

THANK YOU ALL for your help/support. Finally got back out to this remote location. Indeed, someone had interspersed a small gauge wire between the Protector and batter negative up to a terminal where the fridge was connected previously. Changed to heavier gauge and voila!


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ingo21 avatar image
ingo21 answered ·

i do not think it is the BP-65 that stops your fridge from running.

since you mentioned VHF i assume you are on a boat and have one of those Danfoss 12V Compressor fridges.

i would check the cables and connection to fridge and measure the voltage at the fridge.

i have two of those fridges on my boat and most of the time it is the connection somewhere that stops them from working.....

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Sarah avatar image
Sarah answered ·

Hi @glstromeyer@gmail.com the BP-65 has a 90 second delay before disconnecting so it is not likely to be the compressor startup current. What is the disconnect voltage configured on the BP? Assuming it is setup correctly the fault may be a combination of faulty connections, insufficiently charged batteries, voltage drop caused by insufficient cabling or ageing batteries. How do you charge the batteries and does the fridge run when the batteries are being charged ?

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glstromeyer avatar image
glstromeyer answered ·

Thank you for these responses! Much appreciated. Will dig deeper. Forgot to mention:

- system is solar powered with two relatively new 100Ah deep cycle batteries

- the light in the fridge does come on, but fridge will not start when connected from behind the Battery Protector. Does start when connected directly to the batteries - same cable, just connected direct.

- checked voltage at batteries vs input plug of fridge and same at 13.5v

- is the fridge protection circuit somehow (?) sensing the Battery Protector and reacting to it???

1 comment
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klim8skeptic avatar image klim8skeptic ♦ commented ·
What model fridge??

Post a link..

Wiring sizing / length is important to reduce voltage drop.

Share wire specs / lengths between battery > SBP > fridge.

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ingo21 avatar image
ingo21 answered ·

""the light in the fridge does come on, but fridge will not start when connected from behind the Battery Protector. Does start when connected directly to the batteries - same cable, just connected direct.""


does it also start when you connect the cable to input / battery side of the Battery Protector and not the Battery direct.

meaning maybe the connection from your battery to your battery protector does not take the current of the fridge

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