Author Topic: Bavaria 32 - cable size  (Read 1809 times)

Duncancw

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Bavaria 32 - cable size
« on: July 28 2021, 13:22 »
Hi

I have a Bavaria 32 and would really appreciate it if anyone can help?

I've recently purchased a shunt to start monitoring my battery before installing solar panels. The wiring diagram (Panel 424) that comes with the owners manuals f0r a Bavaria 32 states that the cable running to the earth on the domestic battery is 95mm sq. Having used my callipers the actual width of the cable is only 10-11mm which equates to a 35mm sq cable and is considerable smaller than the approx 16mm cable which is standard for a 95mm sq cable.

I need to make up a spare cable to run between the earth on the domestic (140Ah) battery and the shunt.

I want to keep the electrical system as uniform as possible. If I purchase a 95mm sq cable it will be considerable larger than the cable(s) that are current in situ. If I purchase an 35mm sq cable then I will potentially introducing a different amp rating into the system.

What should I do?

I should point out that I only have one domestic battery rather than the two that is in the original Bavaria 32 wiring diagram, so some modifications has taken place (previous owner of the boat).

Yngmar

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Re: Bavaria 32 - cable size
« Reply #1 on: July 29 2021, 11:55 »
Last I checked, area was calculated like this: A = π · r²·

So for 11 mm diameter: π · (11/2)² = 95.03 mm²

Assuming you measured the wire without insulation, everything seems to be as documented.
(formerly) Sailing Songbird  ⛵️ Bavaria 40 Ocean (2001)

tiger79

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Re: Bavaria 32 - cable size
« Reply #2 on: July 29 2021, 12:37 »
Last I checked, area was calculated like this: A = π · r²·

So for 11 mm diameter: π · (11/2)² = 95.03 mm²

Assuming you measured the wire without insulation, everything seems to be as documented.

I think the OP was measuring diameter over the insulation.  95mm² cable is typically about 18mm overall diameter.  35mm² cable is typically about 12mm overall diameter.

Duncancw

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Re: Bavaria 32 - cable size
« Reply #3 on: August 02 2021, 09:48 »
Hi

Yes I was measuring the wire with insulation.

I have decided to go with the larger size 95mm sq (even though it's considerably more expensive). It's probably overkill but I'm not sure what loads I may add in the future and this option means I don't have to worry about it.