Battery Monitor Installation Q's

[MFC]

Hi -
I am preparing to install a battery monitor -- hopefully the Victron 600 which I have purchased -- per recommendations of Maine Sail and others. In doing so, I have read and reread Maine Sail's fantastic tutorial and photo essay on the subject.

See here:

The diagram was removed due to its physical size.

http://forums.hunter.sailboatowners.com ... p?t=125606 (note those silly Hunter owners have the nerve to call Maine Sail *their* own!!!)

Despite all I have learned from MS and others, I have a number of questions about how to install the monitor on my particular electrical system. I have diagramed the battery and charging systems here:



From this drawing (and my afternoon in the lazarette with the multi-meter) I surmise the following:

- I have a starter only battery (can't be used for anything else)
- Only the starter battery can crank the engine
- I have 2 "House batteries" which are technically 2 separate banks but which can be effectively combined to a single bank by placing the OFF-1-2-BOTH switch in the "BOTH" position.
-The isolator directs charging of both house batteries (whether via alternator or AC charger) where as the start battery is charged directly.
-The charging of both the start battery or the house batteries IS NOT impacted by the position of either battery control switch.

Hopefully, I have those basics pinned down now. I have the following questions:

1. Can I monitor this system effectively with the Victron 600? I am concerned that the H1-H2 arrangement is effectively a 2 bank house and that I may have bought the wrong monitor.

2. Does the common negative between the house and the start banks interfere with the monitoring of the house bank(s)?

3. Does the windlass draw from H2 impact the monitoring? How.

4. If I can monitor this system with the V-600, where do I install it (I assume I'd set up a negative buss off of H1 neg with the shunt between the battery and the buss and thin wire to H1 positive) and what changes do I need to make?

5. A tangential but nagging question: do I need to worry about what position the switches are in when the boat is running? I've read stuff about ruining diodes in alternators if the battery switch is off when the engine is running. Is this a concern for me?

Thanks to anyone who has the patience to look through all of this and offer some informed advice.

Respectfully,
grasshopper (Matt)

[barfwinkle]

Good evening

I just finished installing the above listed unit on Rhapsody. Its pretty cool to see the amps/milliamps roll in and out. However, I have a question that IF the manual addresses it, I missed it.

The unit stays on all the time! Shows no drainage, and its so overcast today that it shows no charge either, but is it supposed to "stay on"?

WOW, it also lets you know the significant difference from the old incandescent bulbs, the halogen and the LEDS! Too cool.

Fair Winds and Happy Thanksgiving.

[Steve Laume]

I am sure others will have answers to many of your questions.

1. Don't really know but you are probably okay.

2. The negative is going to be common no matter what you do. Where you attach the stunt could make a difference.

3. The windlass will make a major impact. You are going to be able to see the draw.

4. As for physical location; I found that my Xantrex fit into the original meter hole. I did have to pad out the panel with a teak frame to make me feel comfortable with the clearance behind the meter. The directions were pretty good about how to hook up the wiring.

5. With your Alt going start to the start battery, or any battery for that matter, you do not have to worry about a no load situation on your Alt. A good battery switch will also be okay unless you go to off. What you have is a much better set up than running through the switch.

From the diagram it appears that you have two wires running from the Alt to two separate banks. I am not sure how it knows which bank to charge.

Isn't this stuff so much fun to mess around with? I have installed a whole bunch of stuff, one step at a time and it all works. When I look at the boat now it kind of amazes me, Steve.

[Maine Sail]

This thread was not working right so I responded to it here:

http://www.capedory.org/board/viewtopic ... 040#154040[/url]

[barfwinkle]

Well I was finally able to snake the cabling where it needed to go yesterday. Now I have a few questions concerning the install.

1. To my way of thinking the shunt needs to be protected from accidental contact with foreign objects. I.E. a cover of some sort. Comments?

2. Looking at the wiring diagram in the Cape Dory Owner's Manual it shows a "Ground Bus Bar" with a feed to the back of the "Battery Condition Monitor" (the old analog meter). That feed did exist however, (a) is wasn't a bus bar, it is a bunch of ground wires twisted together and (b) there is no where on the Victron Monitor for such a connection. For now I have it on one of the sub-circuit bus bars. Where should that wire go?

3. I need to figure out how to wire my pilot light now. It may not be overly important, but it reminds me to turn off the battery switch when I leave the boat.

With sunshine forecast for the next few days I am very curious to see just how much the solar panel pumps into the battery. What a cool upgrade.

Fair winds and Happy Thanksgiving.

[Maine Sail]

Well I was finally able to snake the cabling where it needed to go yesterday. Now I have a few questions concerning the install.

1. To my way of thinking the shunt needs to be protected from accidental contact with foreign objects. I.E. a cover of some sort. Comments?

The shunt is in the neg line so it does not technically need to be covered. It can be a good idea as with the Victron the shunt mounted circuit board has 12V, but it is already fused/protected.

2. Looking at the wiring diagram in the Cape Dory Owner's Manual it shows a "Ground Bus Bar" with a feed to the back of the "Battery Condition Monitor" (the old analog meter). That feed did exist however, (a) is wasn't a bus bar, it is a bunch of ground wires twisted together and (b) there is no where on the Victron Monitor for such a connection. For now I have it on one of the sub-circuit bus bars. Where should that wire go?

ALL negative loads, including a starting battery or second bank go on the "load" side of the shunt. NO wires should be between the "battery side" of the shunt and/or directly connected to the battery.

3. I need to figure out how to wire my pilot light now. It may not be overly important, but it reminds me to turn off the battery switch when I leave the boat.

This light can simply pull off 12V+ panel power or directly form the "C" post of the battery switch and ground to your neg buss..

With sunshine forecast for the next few days I am very curious to see just how much the solar panel pumps into the battery. What a cool upgrade.

Fair winds and Happy Thanksgiving.

Sunshine would be good! I have 3" of snow on the boat as I have not yet had a chance to cover it. Only came out last Friday...

[Steve D]

http://www.pbase.com/mainecruising/battery_monitor

[barfwinkle]

Thanks Steve, one picture & a thousand words. I am still pondering a response so I can address my mind's "short coming" but I have to think on it a bit.

Some of my issues are issues of original construction.

So I chime in again later.

Fair winds

[barfwinkle]

Ok, I understand that all neg loads go after the shunt. However, let's take the bilge pump for instance. the neg lead goes after the shunt and that leaves the pos lead. If it is after the switch won't the bilge pump be turned off when the switch is turned off?

How about the solar charger and the ACR. Do their positives go to the pos bus bar? I guess I am missing something here. In my mind when the switch is off anything after the switch is dead. Yes? No?

I hope everyone had a wonderful Thanksgiving. Unfortunately, my beloved Hogs met up with some very hungry Tigers yesterday and its a sad day in the heartland.

Fair winds.

[Maine Sail]

The SHUNT is your measurement device of amps in/out. It is in the negative RETURN to the battery bank. All DC circuits are a loop and thus anything passing through the shunt, like the water meter to your house, will be read. Jump over it or bypass it and the load can't be seen or read..

The VHF and bilge pump can still go direct to the POS battery post and switched 12V can go to your + buss bar. It is only the negative wire that is measured by the shunt not the + wires. This is why your bilge pump or VHF negative wires must be on the LOAD side of the shunt not the battery side.

A shunt is really nothing more than a voltage measuring device. They measure a mV drop across the shunt and it is transposed to amperage by the battery monitor. Thus a 0 mV drop reads as 0 A. A 50mV drop reads as 500A. It reads this drop in the neg return cable to the battery bank..

Shunts come in all sizes but most battery monitors ship with 50mV / 500A shunts..

[Steve D]

If you look at the picture "Loads Yes & No!" you can clearly see the negative and positive connections. Whether it is switched via your panel or a manual/automatic switch, it does not matter, as long as you use these two buses. Then the load will be read and you are coming off the right buses.

[Steve D]

With this alignment, you would never turn your main switch off, as you would want to read all loads used. That is the main goal.

[Maine Sail]

Maybe this helps?


VHF "load" being measured by the shunt:


VHF load invisible to shunt and not being measured:

[barfwinkle]

Well I got 'er dun!

It took me a bit to realize that with no load there was a .25 reading on the meter and I thought that was what was being used and when I turned on the running lights it went to -1.8. After a bit I realized that the original .25 reading was battery "input" from the solar panel and when I turned on any flow that changed according to input-output. Too Kool......

With good direct sunlight, the solar panel (a 5 W panel) puts out a whopping .5 - .6 A (I assume per hour) into the battery.

Now all that is left to do is finalize the installation (everything is just a "rough draft" at the moment).

Fair Winds