Isolator wiring

[YachtGannet]

Hi, first time yacht owner of an Invicta 26 that suffers alternator problems. The alternator’s new, and I’ve stuck an even newer regulator on it. Ignition light goes on with key in position 1 then off when engine fires but I’m only getting battery voltage (currently 12.3ish) on both batteries and on the alternator itself. Battery connections have been cleaned up and tightened and all earths seem to be fine, so I thought I’d take a look at the back of the isolator switch to see how it had been wired. Does the attached look correct? Up until now I’ve always had this on the “Both” position when testing. The wires on the “2” position all go to the waterproof box adjacent to the isolator which I think is a shared positive - from that box the red lead goes up to the ignition panel and the brown lead with the yellow sleeve (I think, based on the cable gauge - it’s part of a heavily taped bundle that heads off to the starter solenoid) is the other end of the alternators B+. Does the “1,2,Both” isolator switch wiring look right?

 

[PaulRainbow]

It should be wired as follows:

Terminal 1 goes to a battery
Terminal 2 goes to the other battery
The common terminal has all of the loads connected to it and usually the alternator B+ cable.

 

[VicS]

Hi, first time yacht owner of an Invicta 26 that suffers alternator problems. The alternator’s new, and I’ve stuck an even newer regulator on it. Ignition light goes on with key in position 1 then off when engine fires but I’m only getting battery voltage (currently 12.3ish) on both batteries and on the alternator itself. Battery connections have been cleaned up and tightened and all earths seem to be fine, so I thought I’d take a look at the back of the isolator switch to see how it had been wired. Does the attached look correct? Up until now I’ve always had this on the “Both” position when testing. The wires on the “2” position all go to the waterproof box adjacent to the isolator which I think is a shared positive - from that box the red lead goes up to the ignition panel and the brown lead with the yellow sleeve (I think, based on the cable gauge - it’s part of a heavily taped bundle that heads off to the starter solenoid) is the other end of the alternators B+. Does the “1,2,Both” isolator switch wiring look right?

It is impossible to comment on your photos without knowing where all the wires go to/ come from.

The basic connections are shown in the diagram below, from the instructions for a "Guest" 1, 2, both switch
(The alternator output is assumed to be connected to the main battery to engine cable at the engine end)

If you have a battery charger permanently connected or solar or wind charging the output(s) might go to the battery terminals or more likely for convenience to the corresponding terminals of the 1, 2, both selector switch.
Any permanently ON circuits , eg a n automatic bilge pump may be connected to the services battery at the selector switch terminal

If a diode splitter, or vsr has been added it will may also be connected to terminals 1 and 2 . ( A diode splitter will also require the alternator out put to be re-routed to it)

 

[PaulRainbow]

The basic connections are shown in the diagram below, from the instructions for a "Guest" 1, 2, both switch
(The alternator output is assumed to be connected to the main battery to engine cable at the engine end)


View attachment 120424

Like i said in post #2