Dual Alt. Schematic

[TAR]

Dave,

I was wondering if I could privately send you a schematic to review, on how our builder is considering installing the SAR-V3 aboard our boats?

Todd Rickard
FPB Yachts

[TAR]

Dave,

My email address to reply to is yachtwork@hotmail.com.

Cheers,

Todd Rickard
FPB Yachts

[Coulomb]

As a matter of insurance policies, we don't provide opinions on drawings made outside of the Company. We spend a lot of time vetting our own drawings, so as long as you are following the wiring diagram the system should work.

[TAR]

Coulomb -

OK - understood regarding liability.

What we would like to do with the SAR-V3 is have it control two separate alternators on the same engine. We are using two Electrodyne HD alternators (150A @ 24VDC). We have on our main dc panel a breaker that turns power on to the regulator (SAR-V3). THEN, we want to be able to switch off the field wire to each alternator independently so that we can run one alternator at a time if desired.

Can we simply put on/off switches on the field wire feeds to each alternator?

Todd Rickard
FPB Yachts

[Coulomb]

Don't switch the alternator field wires. That may burn up switches and introduces transients to the regulator.

Use the DAC, with a toggle switch that selects which "ignition" input to the DAC is selected. Feed the center of the switch with the voltage from the actual ignition switch, or from and oil pressure switch.

[TAR]

Dave,

Unfortunately since this is the only way to contact you, we cannot easily toss about the pros-cons of particular set-ups and details of what we are doing. So at the risk of oversimplification:

In our scheme we will be using a circuit breaker to turn on/off the regulator (hopefully the SAR-V3) driving our two Electrodyne alternators. Then we have two other breakers (not optional to use toggle switch) to turn on/off the field wire going to Alt #1 and Alt #2 so that we can selectively turn a unit on/off. This is how we want to run the set-up.

If we use the DAC, can we achieve this?

Thank you for your prompt response,

Todd Rickard

[Coulomb]

Do you have two alternators on a single engine, or two engines with one alternator each?

[TAR]

Dave,

Thanks for the quick response. We are running one engine, two alternators.

I was wondering if when switching off a field wire, we could eliminate transients to the regulator with a capacitor or something?

Todd Rickard

[Coulomb]

Use the DAC. Wire the engine ignition directly to the regulator so it comes on with the engine.

The use a single pole, double throw toggle switch to select the which alternator is driven. Connect the wiper on the toggle switch to the engine ignition, (same as what you wire to the regulator). Use the two other contacts of the switch to go to the DAC ignition inputs.

The DAC has transient protection build in.

This will allow one or the other alternator to be driven, but not both.

[sv.grainne]

TR:

I have two engines and one SAR-V3 on my sailboat. I wired the dual alternator control as shown in the application diagrams supplied with the regulator and it works fine. Parts are readily available on-line.

Bobby