Anyone see any problems with this electrical system design?

[yachtorion]

Can anyone see anything wrong with this design at all please or have any comments on it?

Abbreviations:

ACR - Automatic Charge Relay (Blue Sea)
RBS - Remote Battery Switch (Blue Sea)
BS - Battery Switch (Blue Sea e-Series with AFD)
AFD - Alternator Field Disconnect
Ant-On - connector on radio that is powered when the radio is on.

"AFD Wire" is actually a loop inserted into the circuit between the engine keyswitch and alternator exciter wire connected to the AFD ports on the engine battery switch.

Engine battery is approx 80AH house battery is 125 AH. Bus wires are v.large others are sized based on a DC wire size table such as in Don Casey's book.

Heater is behind the battery switch so that it can run to keep the boat frost-free when the boat is unattended. Is that a good idea?

Bilge pump is on engine battery as this is hopefully less likely to be discharged and is the first to be charged. ACR can always be manually combined from the remote if needed when on-board.

Thanks!

James

 

[Rigger Mortice]

What size is that water heater? I think you may be a little optimistic to be aiming to get enough heat from a single battery to keep a boat frost free for any length of time.

I don't like the bilge pump on the engine battery. I assume it is automatic and I do undrstand your reasoning. But, if it flattens the battery when you are away then how will you start the engine?

Have you got provision to switch between batteries if the engine battery is flat? (or does the ACR do that? I've not got one)

You don't show the starter motor circuit.
I assume lights etc are off the switch panel

I don't understand the circuit for the sound system. Are you using a radio which is mounted elsewhere and has an antenna relay which is being used for a separate amplifier?

Sorry, I feel I'm being negative, but the schematic isn't very clear and I suspect that there's a fair bit left out.


Edit. I now see from your other thread that the water heater is a diesel one. I should have realised.

 

[yachtorion]

I don't like the bilge pump on the engine battery. I assume it is automatic and I do undrstand your reasoning. But, if it flattens the battery when you are away then how will you start the engine?

Have you got provision to switch between batteries if the engine battery is flat? (or does the ACR do that? I've not got one)

Yes the ACR has a manual "combine" feature.

You don't show the starter motor circuit.

Included in the link to "engine". The diagram is deliberately simplified - intended to convey the overall system rather than each wire.

I assume lights etc are off the switch panel

Yes that's right.

I don't understand the circuit for the sound system. Are you using a radio which is mounted elsewhere and has an antenna relay which is being used for a separate amplifier?

Yes seperate amplifier which has a high current draw so gave it it's own fuse. The relay is fed from the antenna-on output on the radio which in turn is fed from the main switch panel... so when the radio switches on so does the relay.

Sorry, I feel I'm being negative, but the schematic isn't very clear and I suspect that there's a fair bit left out.

Not at all appreciate the feedback!