Balmar 614 regulator: Running brown wire to power regulator from ignition switch

[Patches]

All:

On the home stretch (I think) of my electrical upgrade to a 3 Firefly House Bank.  New Sterling smart charger is in, wired, and working. Located the new Balmar MC-614 regulator in the aft cabin on the small shelf just above the back of the engine.  Ran the new regulator sense wires to the battery bank, which I upsized to 14 AWG because of the long run to the batteries.

I now have to figure out the brown wire which delivers power to the regulator only when the ignition switch is "on."  The choices appear to be (1) run it all the way to the ignition switch from the regulator (panel removal inside, instrument panel removal outside, and long-ish run) or, as Balmar says (2) "in some cases..an oil pressure switch may be used to activate the regulator.  In either case, the regulator's ignition wire must see zero volts when the engine ignition is switched off."

The oil pressure switch location on the port side of the engine looks tempting:  much closer to the regulator and looks easier to install and monitor.

Anybody wired it to this location or have nay strong opinions about doing so?

As always, thanks in advance.

Patches 

[Patches]

Sorry:  Universal m25xp.

I also put a new Catalina engine panel and wiring harness in 2 years ago.  The wire from the ignition switch to the oil pressure switch is blue.

Thanks.

[KWKloeber]

Ok I remember now.  XP.

The OEM fuel pump feed (red?) and OEM alt field excite (purple) harness wires are powered by the key switch.

The oil pressure switch isn't a power wire, it's completing the ground circuit on the OP alarm. If you use that it may screw up how the alarm actuates.

[Patches]

Thanks Ken.

It turns out taking the wire up to the ignition switch was probably easier anyway.  Pretty tight quarters in the engine compartment trying to run a wire over to the oil pressure switch, and there wasn't much left of the stud  on the switch to work with.  Didn't want to disconnect the alternator and all the new wiring on the port side of the engine just to run the wire over there.

In the end, only had to remove the instrument panel and the panel in the aft cabin hiding the fuel tank.  Routed it under the aft cabin to follow the engine wiring harness and up through a hole on the forward shelf (over the back side of the engine/tranny) to the new regulator.

Thanks for taking the time to respond!

Patches

About 16 feet of brown 14 AWG wire for anyone doing this project in the future, and fused at the ignition switch.

[Noah]

Only?! I have felt your pain! I have taken out the engine instrument panel and the fuel tank bulkhead "for the last time", more times than I can count.

[KWKloeber]

the engine instrument panel

those darn things should be on a quick-remove/quick-install rail system!!

To be clear again, for others doing this -- do not use the oil-pressure-switch wire -- it's not a wire that delivers power, it completes a ground circuit from the alarm.

I would think the color would be purple (ABYC color standard for switched 12 volt) although there is no "law" about required color coding.

-ken

[Patches]

And I had to take it out again this morning!

After hooking everything together, programming the new Balmar MC-614 for the Firefly house bank, we got:  no tach/no charge.  This led us to the back of the instrument panel again, which was all good.  Traced it to a 1 amp fuse for the voltage sense wire at the battery.

Now operational after a couple of months, a lot of boat yoga, much research, and a lot of help from others--including this forum, and especially Jon W. who led the way with his meticulous guide to his electrical upgrade.

I now have a 3 Firefly house bank, which fits very tidily in our C34, Mark 1, battery compartments.  Going with the Fireflies allowed me to mount everything into the battery compartment, including the Victron shunt, negative busbar, positive "always on" busbar, circuit breakers, and new selector switch.

I hope to create a separate post in the near future (with photos) showing the layout, components parts, and various decisions made over the past 6 weeks.  My house bank is now 348 amp hours, and (supposedly) can be taken down to 80% without harming the batteries--although I don't ever plan to do that.  No lead acid spills to worry about, or testing of specific gravity.

Patches

[Ron Hill]

Patches : I did the same thing I got the negative shunt and 3 AGM batteries all in the same MK I battery compartment.  However, I ran a #8 gage wire direct to the main negative buss bar (from the shunt) on the inside top of the main electrical panel.  The positive charge wires #4 (duel out) from the alternator also has a #4 negative wire from the Alt. case.

My Balmar regulator is on the engine wall (w/battery temp wire) - inside the head sink door. 

I've had that setup for 20+ years and have never had any charging, starting, fuse or any other electrical problems!!  Also I have gone to stab-in fuses rather than the glass inline fuse holders!     

A few thoughts