Confused battery set up. Two batteries in parallel.

[oldmanofthehills]

Why not leave the engine battery switched on when you're on the boat?

I had never heard of anyone leaving engine power off when at sea, except maybe for transoceanic stuff. No downside at all

 

[KREW2]

If sailor can navigate the oceans to distant lands surely it is not beyond his capabilities to work out how best to operate a 1/2/both switch.
When the engine is running any switching to another bank is done by me.

 

[RupertW]

Why not leave the engine battery switched on when you're on the boat?

Because the low oil pressure alarm sounds very loudly. That’s my new piece if knowledge from this thread - I thought all boats with separate isolator switches and VSRs did this. I now find out after 10 years that apparently they don’t and that’s one reason I liked my other boat which has a 1-2-B switch and an ignition key. This boat just has a push button start.

 

[RupertW]

If sailor can navigate the oceans to distant lands surely it is not beyond his capabilities to work out how best to operate a 1/2/both switch.
When the engine is running any switching to another bank is done by me.

That’s two very different skill sets - my wife is an extremely capable navigator, helm and sailing master but would glaze over fast if I mentioned we have more than one battery or what the bank is or what an alternator or MPPT does. It’s simply of no interest to her, in the same way compression and valves and impellers are just words and a yawn to me.

 

[pvb]

Because the low oil pressure alarm sounds very loudly. That’s my new piece if knowledge from this thread - I thought all boats with separate isolator switches and VSRs did this. I now find out after 10 years that apparently they don’t and that’s one reason I liked my other boat which has a 1-2-B switch and an ignition key. This boat just has a push button start.

Then there's something amiss with your boat. It should be possible to have the engine battery switched on without the low oil pressure warning buzzer sounding.

 

[VicS]

Because the low oil pressure alarm sounds very loudly. That’s my new piece if knowledge from this thread - I thought all boats with separate isolator switches and VSRs did this. I now find out after 10 years that apparently they don’t and that’s one reason I liked my other boat which has a 1-2-B switch and an ignition key. This boat just has a push button start.

Remind us what engine and control panel you have,

You should be able to switch the battery isolator on without activating the engine control panel. Id expect a switch of some sort to power up the panel before you operate the glow plugs if fitted or press the start button to crank the engine

 

[James_Calvert]

I have an "ignition" key on my Bukh panel doing that job.

And as the engine and domestic circuits are both connected as soon as I turn on whichever battery I've chosen, I turn the key and the engine starts.

If the key is in the stop position too long, then the oil pressure warnings will light and sound. Just as well because I gather the stop solenoid can overheat (even catch fire? ) if left energised.

 

[PaulRainbow]

I have an "ignition" key on my Bukh panel doing that job.

And as the engine and domestic circuits are both connected as soon as I turn on whichever battery I've chosen, I turn the key and the engine starts.

If the key is in the stop position too long, then the oil pressure warnings will light and sound. Just as well because I gather the stop solenoid can overheat (even catch fire? ) if left energised.

Funny you should say that James, this is the result of a VP solenoid being energised too long. Luckily, the owner turned the isolator off before there was an actual fire. This wiring was about a foot away from 2000ltrs of diesel.

 

[RupertW]

Remind us what engine and control panel you have,

You should be able to switch the battery isolator on without activating the engine control panel. Id expect a switch of some sort to power up the panel before you operate the glow plugs if fitted or press the start button to crank the engine

It’s a Yanmar 4JHE and I don’t think I’ve ever taken a picture of the control panel. It has a rev counter with engine hours, a fuel guage that has never worked but has a switch to turn it on, a button to start the engine and a button to stop. Yes the isolator powers the panel with no other switches I’d noticed but that’s an obvious idea now it’s pointed out. Perils of sailing mostly on just two boats for years (one with a 1-2-B and not realising other boats were different.

 

[PaulRainbow]

It’s a Yanmar 4JHE and I don’t think I’ve ever taken a picture of the control panel. It has a rev counter with engine hours, a fuel guage that has never worked but has a switch to turn it on, a button to start the engine and a button to stop. Yes the isolator powers the panel with no other switches I’d noticed but that’s an obvious idea now it’s pointed out. Perils of sailing mostly on just two boats for years (one with a 1-2-B and not realising other boats were different.

Most of the Yanmar panels, without a key switch, have a pair of rocker switches. Ign on/off, heat, start. They also have some warning lamps or a 52mm combination widget for the warning lamps. Anything here look like yours ; Yanmar 4JHE instrument panel - Google Search

 

[RupertW]

Most of the Yanmar panels, without a key switch, have a pair of rocker switches. Ign on/off, heat, start. They also have some warning lamps or a 52mm combination widget for the warning lamps. Anything here look like yours ; Yanmar 4JHE instrument panel - Google Search

Nothing there looks quite right but the ones on another google search look just the same except that the key is just a push button and they have a very obvious rocker switch, I have a horrible feeling that I’ve never noticed the rocker switch on mine in a decade and just left it on, Oops and red face if so, but every new discovery is a gain,

 

[PaulRainbow]

Nothing there looks quite right but the ones on another google search look just the same except that the key is just a push button and they have a very obvious rocker switch, I have a horrible feeling that I’ve never noticed the rocker switch on mine in a decade and just left it on, Oops and red face if so, but every new discovery is a gain,

Oh for a nice simple 1-2-B switch

 

[RupertW]

Oh for a nice simple 1-2-B switch

Ex

Oh for a nice simple 1-2-B switch

True - that always worked fine