TravelPower 5kw and Multiplus II

[MrFish]

But in terms of 2 sources of AC. I.e. travelpower and grid will I need to connect an isolating changeover switch to make sure they both never meet?

[PD1964]

4 hours ago, MrFish said:

The first alternator is used for the starter battery as you have stated.  The second alternator is 175A but is not currently used. 

And I take it the 3rd Alternator runs the travel. Is the 2nd alternator not used as it’s a 12v/24v?

  Have a look at this guy if you need a 48v alternator upgrade or a chat about your Travel power, he may be able to give you some constructive advice on the way ahead.

https://fourcountiesmarineservices.com/

 

[PD1964]

12 minutes ago, MrFish said:

But in terms of 2 sources of AC. I.e. travelpower and grid will I need to connect an isolating changeover switch to make sure they both never meet?

There’s normally a change switch fitted, Shoreline, Generator, Inverter with what I’ve seen on older boats, with the TP being the Generator, they never had a Multi inv/charger but used separates. I’m sure @nicknorman will advise as he seams to have the set up and knows how it works, so probably the best man to listen too.

Edited February 14, 2023 by PD1964

[MrFish]

21 minutes ago, PD1964 said:

And I take it the 3rd Alternator runs the travel. Is the 2nd alternator not used as it’s a 12v/24v?

  Have a look at this guy if you need a 48v alternator upgrade or a chat about your Travel power, he may be able to give you some constructive advice on the way ahead.

https://fourcountiesmarineservices.com/

 

Yes that is correct.  It's 12v 175A. Seems a waste not to use it. But I also don't want to overload the engine at the low to mid rpm range

[PaulJ]

29 minutes ago, MrFish said:

But in terms of 2 sources of AC. I.e. travelpower and grid will I need to connect an isolating changeover switch to make sure they both never meet?

Yes.

Most people use a rotary changeover switch, they are not expensive.

 

[nicknorman]

37 minutes ago, MrFish said:

But in terms of 2 sources of AC. I.e. travelpower and grid will I need to connect an isolating changeover switch to make sure they both never meet?

Yes definitely. We have a Mastervolt Masterswitch which does it automatically but a manual switch is a cheaper option.

Edited February 14, 2023 by nicknorman

[IanD]

1 hour ago, nicknorman said:

No this is not correct. We connect our travelpower to our Combi no problem. It doesn’t care whether the neutral is 0v or 115v. And it’s quite happy to provide “power support” by merging the TP supply with inverter output.

I stand corrected -- if Victron say it's OK to have a split phase input, all good 🙂

 

My concern was that I know there's an internal relay in the Victron which bonds neutral to earth when closed; presumably this is locked out if there's 115Vac on the neutral...

Edited February 14, 2023 by IanD

[nicknorman]

15 minutes ago, IanD said:

I stand corrected -- if Victron say it's OK to have a split phase input, all good 🙂

 

My concern was that I know there's an internal relay in the Victron which bonds neutral to earth when closed; presumably this is locked out if there's 115Vac on the neutral...

The NE bond relay only operates in inverter mode when there is no external ac input. If it did operate with “normal” mains input then this would routinely blow eg the shore bollard RCD.

[PD1964]

1 hour ago, MrFish said:

Yes that is correct.  It's 12v 175A. Seems a waste not to use it. But I also don't want to overload the engine at the low to mid rpm range

What made you go for a large 48v battery bank, when your engine is set up for 12v?

 You don’t see many 48v systems with standard Diesel engine fitment, they tend to be on all electric boats and diesel hybrid.