Fuse board to Engine Ground?

[xeitosaphil]

It's personal choice, the VSR wired to the output of the switches allows you to isolate it and all power from the batteries. It also allows you to fit the chargers to the battery side, allowing you leave boat with chargers on, but the VSR not working.

If you fit the VSR to the output side, put a switch in the negative wire to VSR, allows you to turn off unit with battery chargers running.

Why two mains chargers ?

Why not one and use the VSR ?


Brian

Hi Brian thanks for getting back to me, The two chargers I already fitted two years ago while ashore for twelve months. The Ctek M300 came as a two charger package, 1 - Engine Maintenance charger and 1 - House 8 stage 20A Inteligent charger which you could fit leave and forget.
Now I find I want to improve and upgrade my Charging /Battery Monitoring arrangements especially when Cruising, hence all the gauges.

I assume all the VSR cabling is rated at the max charge rate of the alternator and not the battery load capacity?

" switch in the negative wire to VSR " - Any particular type or rating?

 

[halcyon]

I assume all the VSR cabling is rated at the max charge rate of the alternator and not the battery load capacity?

" switch in the negative wire to VSR " - Any particular type or rating?

Alternator or charger, which ever the larger, but as big as you can, minimise any volt drop.

Any switch, it's only switching control load of VSR so say 2 amp switch, with 1.5 sq mm connecting cable.

Brian

 

[VicS]

The VSR only uses a a few miiliamps when not operating and still only a small fraction of an amp when closed. This is the current that will flow in the negative connection so a switch with a high current rating is not required. Physical robustness and IP "waterproofness" rating will probably be the main concerns . BEP supply a 1mm² cable for the negative connection, but that's well in excess of the required current rating.

This page from BEP might be of interest http://www.bepmarine.com/media/product/pro4c27c7b7be03e.pdf
It shows some wiring diagrams and includes a useful table of cable sizes vs current and cable length that you can use for sizing the VSR positive wiring, your battery charger connections, and the alternator output wiring.

Dont not size wiring below the safe minimum size for the expected maximum current . This becomes more relevant than sizing for volts drop on short run lengths

 

[xeitosaphil]

The VSR only uses a a few miiliamps when not operating and still only a small fraction of an amp when closed. This is the current that will flow in the negative connection so a switch with a high current rating is not required. Physical robustness and IP "waterproofness" rating will probably be the main concerns . BEP supply a 1mm² cable for the negative connection, but that's well in excess of the required current rating.

This page from BEP might be of interest http://www.bepmarine.com/media/product/pro4c27c7b7be03e.pdf
It shows some wiring diagrams and includes a useful table of cable sizes vs current and cable length that you can use for sizing the VSR positive wiring, your battery charger connections, and the alternator output wiring.

Dont not size wiring below the safe minimum size for the expected maximum current . This becomes more relevant than sizing for volts drop on short run lengths

A big Thank You to everybody who contributed to this post

Especially Vic and Brian for some most valuable advice on this subject. I don’t know what I would have done without it.

Thanks again fellers Philip