DIY Sparkie

[VooDoo]

Be damned careful. Attached is a wiring diagram from a major component manufacturers 2021 catalogue. Wire it like this and you could be in big trouble if either battery fails......
It is IMPOSSIBLE to isolate a faulty battery and have motor and instruments operating on the remaining good battery.
BEP FU wiring diag.jpg

Hi dmck, found this on BEP Marine online catalogue - thanks for the tip up

However, I have committed all the hardware (battery switch, ACR, fuses block, busbar and panel switch) with Blue Sea System. They are on the expensive side but will have the confidence at sea.

Unexpected and unfortunately incidents can always happened at sea - hopefully with the hand on experience re-wiring the boat, I will be in a better position to fix the issue at hand.

[purple5ive]

You guys are starting to make me look like an amateur!!

[dmck]

Actually, the fix is DEAD SIMPLE! its all in where the connections are made....
I 'found' this whilst helping a mate look for another fault (which turned out not to be a fault) about 3 years ago.
I have since tested several large boats and found the wiring is common, but not exclusive- some get it right.

Attached is a wiring config that is acceptable and will permit the total isolation of either battery and the boat can fully function (motor and instruments-- winches may be different) on the other batt.

Look closely, there is not a lot of difference.

The test is:
turn both battery isolation switches on
turn the battery common switch on -connects both batteries.
check the instruments are working radio gps etc
turn the Instruments-battery switch off- if the instruments remain operational the wiring is OK

[VooDoo]

Just an update on the re-wiring project with the final schematic.

The parts and accessories are already purchased and are slowly arriving - feel like a kid again with excitement and anticipation. Can't wait to get the hand dirty and start putting the theory into practice

Will post pictures of the project as it comes along - hopefully will inspire others to take on the challenge.

[dmck]

You dont show it on your diagram and you may have done so....., but the 2 negative battery terminals MUST be joined

Otherwise... All Good !!! Good choice of battery switch-- almost impossible to make a mistake.... but.. NEVER switch both batteries OFF while the motor is running.

[VooDoo]

You dont how it on your diagram and you may have done so....., but the 2 negative battery terminals MUST be joined

Otherwise... All Good !!! Good choice of battery switch-- almost impossible to make a mistake.... but.. NEVER switch both batteries OFF while the motor is running.

Thank you DMCK for the extremely constructive feedback - i am learning something new each and every day

Haven't received the Bluesea ACR relay charger unit and its installation instructions as yet but do remember reading about the batteries being in parallel for the charging system to works - that is, cranking battery to be charged to full first before switching to the house battery. This wouldn't work without the negative of the 2 batteries being linked.

Planning to have the essential appliances such as bilge auto float circuit, navigational lights, anchor lights, radio connect to the fuse block and -ve bus bar wired to the cranking battery. The rest of the appliances to be connected to the fuse block and bus bar wired to the house battery. What's your view on this set up?

[VooDoo]

Just doing a test run on crimping the 1AWG battery cable - personally happy with the result as the crimp is strong as an ox and the lug is waterproof with labels so can easily sort out which is which when the sheet hits the fan


The hydraulic crimping tool - easily get it from fleebay

The crimping result

After 1st layer of glued heat shrink is applied

After 2nd Layer of glued heat shrink is applied

Final product - with label applied using clear heat shrink

[dmck]

[/quote]

Planning to have the essential appliances such as bilge auto float circuit, navigational lights, anchor lights, radio connect to the fuse block and -ve bus bar wired to the cranking battery. The rest of the appliances to be connected to the fuse block and bus bar wired to the house battery. What's your view on this set up?
[/quote]

What you are planning is pretty standard with no real worries...." but"...

"but"..:
1 If you are having an anchor winch, wire it to the cranking battery and only ever use it with the motor running
2 If you are wiring up an automatic bilge pump.. take care. If you use an automatic switch that is permanently connected to a battery regardless of the battery switch being OFF .. AND.. you connect a manual switch to it as well, you MUST ensure the manual switch is OFF when you are away from the boat--- turning off the batteries is not enough.

If you have the 'fail safe' bilge pump (permanantly connected to a battery) and it operates (water in the bilge) it will 'back feed' voltage to the manual bilge switch- which if ON will back feed that voltage to every other electric/electronic device..... and if any/many are left ON, you may flatten your battery.

3 If '2' is confusing, install 2 bilge pumps, 1 for fully automatic and 1 manually switched !


PS, my crimping tool is the same as yours.

[VooDoo]

What you are planning is pretty standard with no real worries...." but"...

"but"..:
1 If you are having an anchor winch, wire it to the cranking battery and only ever use it with the motor running
2 If you are wiring up an automatic bilge pump.. take care. If you use an automatic switch that is permanently connected to a battery regardless of the battery switch being OFF .. AND.. you connect a manual switch to it as well, you MUST ensure the manual switch is OFF when you are away from the boat--- turning off the batteries is not enough.

If you have the 'fail safe' bilge pump (permanantly connected to a battery) and it operates (water in the bilge) it will 'back feed' voltage to the manual bilge switch- which if ON will back feed that voltage to every other electric/electronic device..... and if any/many are left ON, you may flatten your battery.

3 If '2' is confusing, install 2 bilge pumps, 1 for fully automatic and 1 manually switched !


PS, my crimping tool is the same as yours.

Thank you for the good head up Dmck !!

Will now wire the auto float circuit for the bilge pump to a switch on the console dashboard. This means there will be 2 switches for the bilge pump - 1 for the auto circuit that will turn on the bilge pump via the float switch and 1 for the manual circuit (turn on when needed or when the float switch is faulty).

The Lornstar GX1 electric anchor winch is being installed at the moment and it will have its own circuit with its own solenoid and switch.

On a side note, for those who is installing the your own bilge pump - get the highest capacity pump if you can. Was lucky to be reminded by a senior member here and exchanged the initial 500GPH to 1100GPH pump and the cost difference between the 2 was around $25. You will definitely needed the extra grunt when you most needed !!

[VooDoo]

The candies have arrived !!!

Just a draft layout of how the set up will be. The batter switch will be flushed mount on the console dashboard