Dual battery with VSR - couple of questions

[Crunchy]

I recently purchased a boat with a dual battery setup with a VSR / with a 4-way swtich (1,2,1+2,off). The batteries are Century Marine Pro 600's (Well in excess of the 400CCA required for my 2-stroke 90Hp Yammy)...

My questions to those Ausfish electrical gurus are:

1) Can I comfortably leave the batteries connected (In parallel) whilist charging (I.e. charge them both together)
2) If yes to 1) what amp rated charger do I require for keeping the batteries in good condition? (I am thinking one of the c-tek) I cannot find anything on the century website saying whay kind of charger is required.
3) What do I put the selector switch on when charging? (Assume "off")
4) The previous owner said disconect the negative wire from the VSR before charging, I assume this is correct?

As always thanks heaps for the help....

Cheers
Crunchy

[tropicrows]

Here what I do.

I have a start battery for the motor, and second battery (house battery) for everything else.

While boating both battery’s are turned on (not in parallel). The motor charges the start battery and only when it is charged, switches over to the house battery via the VSR.
At home the battery switches are both off and I only ever charge the house battery, I do not disconnect any cables/wires etc. Just connect the charger to the common Neg. and the Pos terminal on the house battery. Never have any problems in 2 years.

[dnej]

In regards to charging, I turn off the switch when boating day is complete.Then I plug in my charger, to a plug I have set up, especially for the purpose.

I made a small box, with an on off switch , so as I can change plugs, to charge an alternate battery.

The wiring runs directly back to the batteries, and not through the switch, so everything remains isolated.
David

[Chimo]

With my Auto Battery Coupler (ABC) I just put the battery charger plus on the battery plus terminal and the Neg battery charger Neg on the Battery Neg and turn the charger on. The ABC allows me to charge the house and motor battery together and although I usually charge via the start battery I was told I can charge thru the house too if the mood takes me. The ABC does whatever it does and I just remove the chager and go boating when I do that. Gotto luv that.

Cheers
Chimo

[Crunchy]

Here what I do.

I have a start battery for the motor, and second battery (house battery) for everything else.

While boating both battery’s are turned on (not in parallel). The motor charges the start battery and only when it is charged, switches over to the house battery via the VSR.
At home the battery switches are both off and I only ever charge the house battery, I do not disconnect any cables/wires etc. Just connect the charger to the common Neg. and the Pos terminal on the house battery. Never have any problems in 2 years.

Thanks for the comments Tropicrow...
Similar setup by the sounds, but I don't differentiate between start and house battery, I use each battery alternately between trips. I.e. "1" or "2" never "1&2". So either 1 or 2 does both the cranking and the electronics (& pumps) during the trip (And has a rest next time out). This seems to work well and I have not had to swith batteries at sea as yet (They get 10amps while motor is running). I'm sure the setup I have will be common. The batteries I guess are not actually in parallel unless the the swith is selected to "1&2". Think I'll draw a picture and post it...

Tropico, so no issues running charge current through the VSR? The VSR still swithes the current to the second battery even if the selector swtich is "off"?

Cheers
Crunchy

[Crunchy]

In regards to charging, I turn off the switch when boating day is complete.Then I plug in my charger, to a plug I have set up, especially for the purpose.

I made a small box, with an on off switch , so as I can change plugs, to charge an alternate battery.

The wiring runs directly back to the batteries, and not through the switch, so everything remains isolated.
David

Hey David, sounds like two seperate systems rather than connected through a VSR?

[Crunchy]

With my Auto Battery Coupler (ABC) I just put the battery charger plus on the battery plus terminal and the Neg battery charger Neg on the Battery Neg and turn the charger on. The ABC allows me to charge the house and motor battery together and although I usually charge via the start battery I was told I can charge thru the house too if the mood takes me. The ABC does whatever it does and I just remove the chager and go boating when I do that. Gotto luv that.

Cheers
Chimo

Cheers Chimo, is the ABC something similar to a VSR or is it only used for charging?

Cheers

PS Yep will remember to use that multiple quote option in future

[Chimo]

Hi Crunchy

The ABC does the same things in the boat with the motor providing the charge. it also disconnects the house battery from the motor / starting spikes until the volts are stable ie no more spikes to bugger up electronics etc etc

Its a local Qld bit of gear made on the Gold Coast and was installed in my rig by the guy who makes them. Mines about 10yrs old now and still doing what its supposed to do.

I can give you contact details for the man if you wish, see pic too.

Cheers
Chimo

[dnej]

Crunchy, yes that is correct, but I can use the output plugs for aux power as needed, while operating the boat.It is just a cheap way of not having to go to the battery for charging purposes at home.
David

[TheRealAndy]

A good charger is designed to charge a single battery.

A VSR is designed to turn on when the voltage on the primary battery exceeds a preset voltage, and switch off when the voltage on the primary battery drops below a certain value.

The PRIMARY purpose of a VSR is to isolate the primary battery so that it does not go flat. Its SECONDARY purpose is to allow the secondary battery to be charged.

A VSR is not designed to be a battery charger.

If you want to do everything by the book, charge each battery seperately. Charging the primary battery and the secondary battery via the VSR is probably not going to be an issue, but you paid good money for you batteries so why not do it properly? A well looked after battery will last you a long time. Once both batteries are charged it probably wont hurt to use the charger on both at once to keep them topped up.