Mahe 36: Batteries And 12vdc Systems

[IrieCat]

does anyone know the specifics on the battery bank that comes stock on the Mahe? thanks in advance!
lk

[DtM]

What precisely do you want to know on the batteries?

daniel

[DtM]

I will look on Friday for you.

[lstyles]

What kind and size batteries do you guys have on your Mahes?
thanks,
Lori

[Scott730]

Lori
Your timing couldn't be better, I lost my starboard battery last week (less than a year old) so I've decided to replace my 3 105 ah house batteries and one 105 ah starter battery with 4 31 AGM batteries for the house and a 24 AGM for the starter battery for the starboard engine. On my boat all the batteries are housed in the port engine hold, that is where I'll place all the house batteries and move the starter battery to the starboard engine hold. I'll also add a "centerfielder" from Balmar so I can use both Altenators to charge the house batteries and a temp monitor on the Altenators so they don't over heat charging the AGM's.
This increases my house to 440 ah's from around 315 for the original configuration.

Scott

[pguillemin]

Scott
Could you send me a drawings

Originally Posted by Scott730

Lori
Your timing couldn't be better, I lost my starboard battery last week (less than a year old) so I've decided to replace my 3 105 ah house batteries and one 105 ah starter battery with 4 31 AGM batteries for the house and a 24 AGM for the starter battery for the starboard engine. On my boat all the batteries are housed in the port engine hold, that is where I'll place all the house batteries and move the starter battery to the starboard engine hold. I'll also add a "centerfielder" from Balmar so I can use both Altenators to charge the house batteries and a temp monitor on the Altenators so they don't over heat charging the AGM's.
This increases my house to 440 ah's from around 315 for the original configuration.

Scott

[lstyles]

I'd like to see that too. Did you put the new batteries in the same location. Access to my batteries is so difficult that I havent had time to get in there and check them out. All I can see is that they say "Freedom stationary marine batteries" and there is a sticker on the side that says 105ah x 12 v. I am assuming they are no maintenance wet cells but just wanted to confirm with someone else. What were the make and type of batteries that you replaced?
Lori

[Scott730]

They are lead acid batteries, no maint. Don't believe it. only gel or agm are no maint..
As soon as I finish the drawings I'll post them. Need to combine the balmar schematics with what I've found on the boat. I'm still considering moving the batteries to under the port berth.

Scott

[pguillemin]

Scott
Keep the batteries in the ER
Opening the bunk to the ER will bring you fumes and smell + longer cable runs.

[Scott730]

Philippe
Good point, I've been going back a forth on it but now I'll keep them in the ER.

Thanks
Scott

[MKB53]

Guys

Has anyone replaced their batteries? Any info on the easiest way to get batteries and battery box out (to access the connections inside the battery box) would be greatly appreciated.

When it comes to accessability it is like the old Mini!

[Scott730]

Martin
On my boat, you can remove the batteries by sliding the furthest one on the port side to the hull (left) and then back to the stern, then you slide the next one all the way to the port hull and pull back to the stern, continue on till all are removed. It's not an easy job. Disconnect the positive leads first and remove wiring, then you can get at the negative leads in the back (you will bruise your arms and hands getting the negative bus bar off! I assure you, you will drink heavily after doing this! ) The only way to access the inside of the battery box is the sliding off the hatch on the top of the box which is just under the deck by a few inches which means you can slide the hatch off but you can't access the inside of the box!! I think FP did all the wiring before they installed the deck of the boat, once they did that, it made access to the battery box impossible. There is really no reason to get inside unless you want to rewire the battery configuration. However, that is exactly what I wanted to do (on my boat all the batteries are on the port side including the starting battery for the starboard engine, I wanted to move the starting battery to the starboard side and add a 4th house battery in place of the starting battery. I also had a loose connection inside the box that was touching another lead causing the starting battery to be in parallel with the house bank (thereby draining the starting battery). I actually bought a fiber optic scope with light so I could cut off the front of the battery box without cutting any wires inside, I inserted the scope in thru the hatch and watched the saw blade from the inside as I cut out the front panel. Everything worked out fine, But I would never suggest that anyone do this since I would never try it again.

Scott

[MKB53]

Thanks Scott

Mine has 3 house batteries to port and the starboard battery to starboard and easily accessible! (Duh!)

Based on my memory of my battery box I don't see how the batteries can be slid to the port side unless the end panel comes out but I will check.

At this stage I don't need to get them out but I did want to get into the connections so that I could wire a shunt (for a battery monitor) in the negative line with as few joins as possible.

The supply from the neg terminal to the switch box is a bar so I guess that will run to the neg terminals for all circuits (on the starboard end of the box) which means I don't have any option. As you have looked inside with a scope you could probably confirm that - I was going to try to get the sliding panel off and use a mirror.

I may just resort to drink as you suggest will happen. Murphys Law says we will need to get in there to fix something so why don't they make it easier!

As an aside I am also having a lot of fun getting the wires for the sensor and dedicated power from the shunt to the monitor. At least the monitor neatly replaced the standard voltage meter, that was the only easy bit.

[jean1146]

Everytime I look at the batteries and think about pulling them out I do have cold sweats.....who ever is going to do that is going to want to kill me because I know I can't do it.Scott I thought you had cut a hole over the batteries and installed a hatch? Anybody has a better idea,may be Philippe could tell us if he has done it.
JC.

[Scott730]

Martin
The batteries have more headroom on the left side of the box so you can lift them over the lip, bearly, then slide them out. I also mounted a Xantrex battery monitoring system and ran a jumper from the negative starboard terminal to the shunt, it works fine. I mounted the shunt on the bulkhead section just in front of the battery box. And I also had a hell of a time running the wires (I suggest that you run 2 pull lines using a snake or a wire coat hanger, use one to pull the wires and the other for future needs) I snaked them along the wire chase that runs from the aft storage locker to the hanging locker in the port berth (remove the plywood panel for access).
Have fun.

Scott