Dual Battery and VSR

[Robsrock]

I am a newbie to the forum having come from a forum that was more oriented to Vic Fishos so I thought I would reach out on a topic that no doubt has been well covered although I am looking for some specific advice.

I will start with a bit of a description of the set-up of the boat which has been in place and been functioning ok since I have had the boat (2011).

My rig is a seafarer Cuddy 2002 with a 90hp Johnson on the back.This was a replacement for a very similar set-up which was stolen a off my driveway in late 2010 ( two days before Xmas to be precise)

I am looking to get some advice on the twin battery set-up.

The current battery set-up uses the negative leads from both batteries and engine go into the battery isolator switch and both batteries are connected via the positives connected by a cross over lead - not sure if this ok as most oif what I have read is that it all needs to link back through the positive leads ??

I need to replace both batteries now as they are well past their used by dates and dead due to my mistake of leaving a few electronics on last week.

I also want to install a VSR so my question is. Will the VSR work with this set up and do I simply intersect the linking positive leads with the VSR? .

Need some thoughts here.

regards

Robsrock

[fragmeister]

Welcome Robsrock.

I hope you enjoy your stay at the Fishraider forum.

There are a lot of misconceptions around electrical systems in general because there are so many variables.

The blanket rules that many follow don't always apply.

Switching the negative will work but to to avoid potential issues you should follow the conventional wiring setup for dual batteries which is shown in the diagram below.

Cheers

Jim

[Robsrock]

Ok I have now replaced both batteries during the summer and it now time to change the old set up where I had a battery switch and was forever forgetting to switch it over so both would charge. DOH!

I am about to install a Voltage Sensitive Relay (VRS)- and have a couple of questions for those marine sparkies or others who have gone down the same path .

1. Working from the above diagram - do i need to put in circuit breakers on the positive leads from the VSR??
2. I have seen a number of set ups where there is a battery switch and a VSR in the same loop so doesn't the VSR do the same as the switch ?? or do i need both.

I have a VSR that allows me to parallel both batteries in an emergency start situation.

Thoughts welcome - pictures will also help me !

[Robsrock]

Hi Guys - looking for some advice - I know its winter and the boating activities tend to diminish - hoping someone has time to help.

thanks Robs rock

Edited July 9, 2016 by Robsrock

[antonywardle]

I don't think that a lot of current flows out of the VSR to the battery for charging. You can put one in but I don't think you'll need one.

Where the circuit breaker is best used will be between your battery and your toys. It needs to be less that the rating for your wire

but enough so that all your toys running don't trip it. My wire is 80AMP I think with a 50AMP circut breaker and I only draw about 20 I think it is

My toys:

Fishfinder, VHF Radio, 27Mhz Radio, Stereo to listen to the fishing report, Nav lights, a USB charger, bilge pump.

I'll PM you in a bit. Just a bit busy ATM

Cheers

Antony

[Ocean Addiction]

Hi Robsrock,

I just finished putting a VSR in my Bayliner. I seem to be running the same amount of gear as Antony listed above and the little starter battery worried me.

After quite a lot of research on the internet it seems as though there are a couple of ways people hook them up. Im certainly not a marine electrician but I was willing to have a crack myself.

I got a fair bit of my information from US wakeboarding blogs/sites (they seem to run a second battery to power a massive stereo) and from Jaycar (go during the quiet times and you can usually find someone willing to help out) as well as the instructions that came with the VSR.

Here is my setup. I installed 2 new Bluesea fuses along with the VSR and switch which allows me to parallel the batteries if the start battery goes flat. The outboard, accessories and bilge pump were already fused. The negatives run to a power post located underneath the switch. Ideally it would have been nice to install the VSR above or below the switch as it would have been much nicer looking but I didnt have enough space.

My only task left is to work out how to run the bilge directly off the battery rather than through the switch (that bundle of black wire in the corner). That way if I ever have it switched off and it fills with water then it can empty itself out.

David

[Sigma]

Hi guys,

Just an alternative if it hasn't been mentioned before.

I was going to install something like you have Ocean Addiction but after reading some other forums, people recommended to install and ACR (Automatic Charging Relay) instead of a VSR as the ACR is fully automatic.

No manual switching on the switch between the batteries as the ACR does it for you.

I took the advice and purchased a Blue Sea 7649 Mini Add-A-Battery System. I'm in the process of installing it myself but I've gone a bit overboard and installed a Fuse Box as well.

Will let you know how it all goes once I get around completing it.

Anyone out there who has had an ACR installed.....are they that good?

[Robsrock]

Antony and David (Ocean addiction)

many thanks for your input - I think we are getting really close with your input. My main sticking point was the inclusion of a battery switch and the VSR until David clarified the purpose about the switch was to parallel the batteries if the start battery goes flat. Nice and clean the way this works by the way.

My VSR has a switch built in for this so I feel I do not need the switch - as that is what I started with and I did not manage it very well and had two dead batteries at the ramp at 5.30am - not happy that day.

[Ocean Addiction]

I thought that VSR and ACR were pretty much the same thing? Im really interested to find out what the difference between VSR and ACR is though! Can anyone help?

Robsrock, Yeah I could have done it without the switch which would have ended up being a much cheaper option. I think the VSR itself was only $45 but the switch added close to $100 to the job (plus the cables and M10 connectors that I had some trouble finding). I really like the idea of having the "all off" and "combine" options - (edit) which were not included with my VSR.

Which VSR did you get?

David

Edited July 11, 2016 by Ocean Addiction

[Robsrock]

Hi David

I got the Maston VSR with override switch - so I can run both batteries together if required .

http://www.batteriesdirect.com.au/shop/product/23314/ma98404.html

I have a switch from the old set up but I want the VSR to do the work for me so I keep the starter battery as secondary battery runs the other stuff. I have an 80 AH battery with only a few electrics running of it - radio - sounder and occasionally the live bait tank when stationary.

[Robsrock]

Guys this is what my set up will look like

I will add in a couple of breakers on both sides of the VSR,

Edited July 12, 2016 by Robsrock

[antonywardle]

HI

that picture looks fine

I don't think I'd worry about the circuit breakers on either side of the VSR. I'd have one between

the house battery to the boat toys. Do you have a 1-2-both-off switch? The lets you start the engine

using either or both batteries. In your current setup, I'd leave it on 1 assuming that that is where your starter

battery is.

Also, I sometimes remember to take a jump start pack. Pretty cheap insurance even though I have two newish batteries

and I put them on a charge the night before. This cold weather can kill a suspect battery.

Good luck, it looks like you are just about there.

[Robsrock]

Antony

As you say I am pretty close now. I will not include a switch as there is one intergrated into the vsr for emergency starting.

The vsr does the work for me this way.

[Norton 79]

Hi. My first post here. I am in the process of installing a acr ( auto combining relay) from blue seas. It has a cable that you can run to the starter to auto disconnect both batteries while starting and will automatically combine them after the start battery is fully charged to charge the house battery. It is wired much like Robsrocks pic above with another cable connecting to the start circuit if wanted