Voltmeter--RIP?

[Tom Keevil]

The shunt may not look exotic, but it is essential. All of the current used by the boat (many amps) runs through the shunt. The digital ammeter could not handle this much current. So instead, it measures the voltage drop across a shunt of a known resistance (a drop of only millivolts), and uses that to calculate the current flowing through the shunt. You can not leave it out, even though it doesn't look very complicated or sophisticated.

[Maine Sail]

The shunt that was provided with the Link-LITE appears to be nothing but a buss bar with two battery lugs and two screws for the current sensing leads. I see no electronics, and the meter shows all 4 contact point (and the bar) to be, electrically, the same point.

The shunt for the LinkPRO is an entirely different piece of equipment. See the photo of the Link-LITE shunt in this link:
http://www.tosimplify.net/2011/04/xantr ... recap.html

Mitchell Bober
Sunny Lancaster, (Where I am currently rubbing Ben-Gay on some seriously sore muscles.) VA

It is a shunt there are no electronics. The Link-Lite and Link-Pro use the identical specification shunts, though they have changed in looks over the years. The Victron also uses the same specification although they slap a PC board onto it so you can simply plug-n-play. They both do the same exact thing..

All a shunt does is measure millivolt voltage drop from one side of the shunt to the other. A mV is one thousandths of an amp. The Xantrex and Victron shunts are 500A, 50mV rated.

What this means is that with a 500A load the shunt will drop 50mV across it and your meter would show a 500A load. With zero load there is a zero mV drop. By knowing the behavior of the shunt at different loads the monitors can be programmed to read the mV drop and transpose it to amps from .01A to 500A.

The piece of copper between the two large studs is what is used to measure the mV voltage drop...

[Dean Abramson]

Anyone have any comments on my proposed cheapie solutions?

Really, it's not like I haven't been generou$ to the boat this year. I may rename it "Pentagon."

[Kevin Kaldenbach]

Dean, I have been watching your post for the past twelve months or so. Judging buy the questions you were asking I thought you were getting her ready for an extended cruise. If you do not need to count amp hours with the kind of sailing your doing then get a cheep volt gauge if you want. Its going to be inside the boat anyways so perhaps you can skimp on quality. Since it is in parallel with the electrical system if it get corroded it will most likely just stop working. I would not feel the same about an amp gauge. If I was near my boat I would give you my old one but it will a while before I go back.

[Dean Abramson]

Part of my reason for wanting to use the cheapie solution is that I assume I can just wire it like the old one was. Like I said, there is a momentary toggle switch which sends the voltage from either Batt 1 or Batt 2 to the gauge.

Maine Sail's tutorial (linked to by Zeida) is, as usual, fantastic. But I have a lot of trouble with electricity, so I am still uncertain of what I would wind up with if I, say, do exactly what Maine Sail shows.

Maine Sail, if I use your Victron set-up, wouldn't I need a separate gauge for each bank (batt)?

OR, is it the case that I would be able to use the Victron's full features for my House Bank (Batt 2), but still be able to get just a voltage reading for Batt 1? (That does not, to me, appear to be the case.)

I am trying to do what is simple, (and, if possible, not too pricey), and requires only the single hole that is already in the panel. Mitch, didn't you do just that? If so, what did you wind up with in terms of functionality? Please keep in mind that you are speaking to the electrically-challenged.

Kevin, I was doing a combination of long-term boat improvements, and getting ready for a three-week trip, which I have now already taken. To comment on your comment, I do think that I can do without knowing amp-hours usage, simply because I have always been okay without that information in the past. I like to transit in the morning a lot. In Maine, that, more often that not, means motoring. We mostly charge Batt 2, and we never have any issues. With our type of cruising, I rarely ever go three days without some motoring.

Dean

[Dean Abramson]

Further web browsing makes it look like the Victron 602 would be the way to go. Full-featured, but one gauge for two banks. It also looks fairly easy to install.

Zeida, I cannot tell which model you have. Is it on one bank or two?

Maine Sail, I see that you have a 602S in your tutorial. What is the S about? At Jamestown Distibutors, I find only the 600 and the 602.

Does anyone know the exact size of the hole in the panel on a CD31? If this 602 fits, it might be the best possible solution.

One thing that confuses me is this part of a customer review:
"It should be more clear. It will monitor two batteries only if they are for completely seperate loads, where as I have two batteries in parallel but it seems to monitor them as one big battery as I ran both negatives from each battery to the BAT lug on the shunt and then one larger lead from the shunt to my distribution center."
Has he hooked it up wrong?

[Zeida]

Dean... I got the Victron that reads just the one bank... the main housebank -which in my case- consists of 3 Group 27 batteries wired in parallel. The other bank is just the one starting battery, actually more like a back-up battery, because I always start with the main switch on the house bank. That's what my Victron monitor reads. It also does fit perfectly in the old Link 10 hole.

At the last minute I chickened out and called an electrician to do the installation. I already had a shunt from the Link 10 so his job was simply to make the proper connections. I did run the wires through all the tricky places myself and had most of it ready for the guy, who did as Main Sail suggests in his sample. So far, it's working fine. I had to get used to the new "vocabulary" but once I understood the new terms, I'm fine with it.

[Zeida]

Dean, forgot to mention that I bought the Victron 600S, also from jamestown distributors.

[Zeida]

The 600S is the one for a Single bank monitor. The S stands for Single, I assume. It is also a bit cheaper than the 2-bank monitor, which I decided I did not need.

[Tom Keevil]

We have an old Link 10 that monitors only our house bank, and that works fine for us. It's really not all that important to monitor your starting battery, as it uses only a small amount of it's capacity to start the engine, and is then recharged in a fairly short time. It's your house batteries that need watching.

[Maine Sail]

Further web browsing makes it look like the Victron 602 would be the way to go. Full-featured, but one gauge for two banks. It also looks fairly easy to install.

Zeida, I cannot tell which model you have. Is it on one bank or two?

Maine Sail, I see that you have a 602S in your tutorial. What is the S about? At Jamestown Distibutors, I find only the 600 and the 602.

Does anyone know the exact size of the hole in the panel on a CD31? If this 602 fits, it might be the best possible solution.

One thing that confuses me is this part of a customer review:
"It should be more clear. It will monitor two batteries only if they are for completely seperate loads, where as I have two batteries in parallel but it seems to monitor them as one big battery as I ran both negatives from each battery to the BAT lug on the shunt and then one larger lead from the shunt to my distribution center."
Has he hooked it up wrong?

Dean,


Yes, as near as I can tell, that guy installed it wrong.

Unless you really want to know the voltage of your second bank, which is not really all that necessary, I feel the 602 is a waste of money for the extra they charge for simply monitoring the voltage.

Really all you need is to monitor the house bank, which is the one that is being used. There is no need to even start your motor on your start bank so if you run the boat on ALL every few weeks that battery will remain topped up and you'll replenish any self discharge losses.. If you can't start your motor off the house bank, even at 50% state of charge, something is drastically wrong with your batteries, wiring etc..

Our battery switch has basically not seen the ALL position or #2/Reserve for over 5 years. For over 20 years I have always started my engines, big and small, on our deep cycle house banks. Keep in mind that most any deep cycle house bank in parallel or series, or series parallel will have more cranking amps than a single "starting" battery. I do test that battery periodically and some times will run the inverter off it when using power tools to "load it up" but other than that it is treated as a reserve bank and the house bank does everything.

So if using just one bank you only have one bank to monitor and you can save about $50.00...

[Steve Bryant]

For those who might want an inexpensive digital voltmeter, I installed a Datel DMS-20PC-0-DCM on my CD25, which has very modest battery usage. They are used quite a bit on motorcycles and the front of the meter is weather resistant.

It was $56, which includes the optional mounting bezel and it only consumes 2ma at 12 volts, so even if left on constantly it doesn't put any significant drain on the battery.

You can use the same test switch that is on the battery monitor that you have and just abandon the analog meter or make a blank to fit in the round hole and install the meter in it. It measures about 1" x 1 1/2".

It's the least expensive digital meter that measures in hundredths of a volt that I have found out there. If you just want a simple solution to keep an eye on the relative state of your batteries and have a better idea of the charge than the analog meter, I highly recommend it.

Heres a link to the Datel site:

http://www.datelmeters.com/cgi-bin/webs ... eters.html