Fridge and voltage drop

[marioxp]

Fridge in Bavaria 32 2003 occasionally stops working.

I measured the voltages and noticed that when the refrigerator is running the voltage drops to about 10.5V. The batteries are brand new and the voltage is a constant 12.6V. I checked the cables, and they're fine.

What could be the reason for this voltage drop?

I guess the reason the refrigerator stopped working was the voltage drop.

[tiger79]

Mine used to stop working occasionally.  Traced it to a faulty relay in the switch panel.  Swapped it for an unused one, and all is well.

[marioxp]

Mine used to stop working occasionally.  Traced it to a faulty relay in the switch panel.  Swapped it for an unused one, and all is well.

Relay?

Did you mean switch?

[elias]

Hi , the voltage drop can be also due to inappropriate wiring . Especially if they run far from the source . I changed mine to 4mm2 cross section for less losses .

[tiger79]

Mine used to stop working occasionally.  Traced it to a faulty relay in the switch panel.  Swapped it for an unused one, and all is well.

Relay?

Did you mean switch?

No, I meant relay.  The various circuits on my boat are controlled by relays (the dark grey rectangular things on the circuit board in this pic).

[Yngmar]

I measured the voltages and noticed that when the refrigerator is running the voltage drops to about 10.5V. The batteries are brand new and the voltage is a constant 12.6V. I checked the cables, and they're fine.

What could be the reason for this voltage drop?

Either the cables are undersized, or they aren't fine. Often the fault is at the crimped connectors when moisture causes corrosion which causes high resistance. Check again.

[marioxp]

Either the cables are undersized, or they aren't fine. Often the fault is at the crimped connectors when moisture causes corrosion which causes high resistance. Check again.

Wire is 6 mm2, it is 5-6m long. I changed connectors with brand new..

We noticed that when pump of electric toilet run voltage drop even more, voltage on battery drop negligible.

[Yngmar]

Is the wire itself corroded (copper gone brown/green on untinned wire)?

10.5V is where the fridge controller switches off by default to protect batteries from deep discharge.

[GeoffV]

No, I meant relay.  The various circuits on my boat are controlled by relays (the dark grey rectangular things on the circuit board in this pic).


I have a similar problem with a relay - can they be replaced?

[tiger79]

I have a similar problem with a relay - can they be replaced?

Yes, they just plug in to the circuit board.

[GeoffV]

...... and finally, a supplier? :-)

Thanks.

[tiger79]

...... and finally, a supplier? :-)

Thanks.

Don't know, I just swapped the dodgy relay with one on an unused circuit.  There'll be some sort of part number on the relay, so it should be easy to find a replacement.

[JEN-et-ROSS]

Try CPC Farnell,  (sales@cpc.co.uk) with the serial number of the relay in question.
Also, do any of the crimped terminals get warm/hot when powered up?....they shouldn't.......Bill.