FreedomYachts.org

I'm installing a battery monitor and am trying to decide how to set the battery capacity for the monitor.

My battery system consists of three 105 amp-hr AGMs wired together for a house bank that receives the charging current from the alternator and the charger.

a fourth 105 amp-hr AGM is used for the starting battery and it is charged by an Echo-charger from the house bank.

Should I set up the battery monitor battery capacity for 315 amp-hr house battery or the 420 amp-hrs combined battery capacity?

Thanks

You need to refer to instructions for battery monitor you have but i would suspect you should set up monitor for each battery separately. 315 or closest value for house and 105 or closest value for engine bank. That is how my link system is set up.

Rich Fontaine
s/v Liberte
F36, Portsmouth, RI

Agree with Rich. You'll likely set up the monitor for 315 amps or something close. Some monitors only monitor a single bank. Others can monitor two or more. Many advise that monitoring the house bank is all that is necessary since the start bank is rarely drawn down if used for starting alone.

Brien

I set my single channel Xantrex up to monitor house. I watch start with the analog meter but there's not much to watch, a normal start cycle would only suck up an amp hour or two. Th start is isolated from house and would only be connected to house in emergency. I have not had to do this in the 7 years I have had the system installed.

Another note, if you have installed these big batteries under the chart table like I did, be sure to secure them on the side as well as on the top. I found that on starboard tack in lumpy seas the batteries, even though secured down, will want to slide inboard and place a lot of pressure on the chart table fascia. So much so, in my case, that the fascia screws began to pull out of the chart table fascia. I installed longer screws to hold things together when I discovered this but, when I got back to the dock I added a heavy duty cargo strap to provide lateral security.

Thanks for the advice. My old Link-20 display finally gave up the ghost and I'm installing a VICTRON BMV600S to replace it.

I think I'll set up the single battery monitor with just the house 315 AH capacity setting. Hopefully the monitor will account for the AH siphoned off by the Echo-Charge to the starting battery.

Mike - As to the battery location - My system is now pretty much identical to the one you sent me pictures of except I built a battery platform under the port settee fiber-glassed into the hull with four battery trays screwed down to it and the batteries strapped to them. (The weight of the batteries and the relocation across from the water tank helped remove a bit of list from having the batteries and water tank on one side.) I see your point, though, and I think I'll get some SS threaded rods and secure the top of batteries better than the straps do. I now have a Charles Isolation Transformer where the batteries used to be.

I moved/replaced the charger from under to outside the nav station and put in 3 size 31's- screwed some aluminum L channel to bulkheads and ran alunimum bars (encased in clear plastic hose) on top and in front of batteries to secure them, bolting bars to L channel. Very secure, and easy