Voltage drop cutting out fridge

[bluemistgosport]

Help, I have an issue with my fridge short cycling due to a drop in power. The scheiber voltage is Dropping to 11.8v when the fridge cuts in over night however my victron BM is showing 12.4v and 90% so i know i have enough power in the batterys, can anyone help with how to adjust the panel so this doesn't keep cutting out the fridge.

[Zanshin]

The fridge voltage cutoff settings aren't in the Scheiber panel, they are on the compressor unit itself. Chances are that your compressor is a Danfoss BD35 or BD50 and the controller should look like this:


By choosing the correct resistance between "C" and "P" you can adjust these values. While some stores will sell you this for up to 5€, the actual resistor costs 0.001€; if you don't dabble in electronics just find anyone who does and they'll give you the resistor.

Here's a link to the documentation for one of these Danfoss controlling units: operating instructions. See page 10.

[zaphod]

If your Scheiber panel indicates 11.8v at the same time as your battery monitor indicates 12.4v then you have a voltage drop in the feeder circuit to your panel. The first step is to check your connections at the panel.

The low voltage cutout on the compressor is there to protect the compressor and it's control module. You need to make sure it is getting the required voltage rather than "hacking" the module to force it to running on a lower voltage.

[panoramix]

The voltage drop of 12.4 to 11.8 is caused by thin electric wires and/or poor connections.

Check your electric wiring + and - between the scheiber panel and battery.

[Zanshin]

That voltage difference is significant, although I have always found that the panel readings on my boats have been unreliable at best. Regardless, 11.8v is not low enough to cut out the fridge compressor. Do you have a multimeter to measure the actual voltage at the fridge and compare it with both the Scheiber and Victron values?