Battery Monitors

[D Tharp]

OK so I just received my LED lights witch I will install this week.
Also will order my controller for my SOLAR PANELS.
But I want to know what brand BATTERY MONITORS people are using. At a good price.
I am trying to get up to speed on all this.

THANKS DAVE

[John Hussey]

Look at the cheap one at Wal-Mart, in battery section, hanging up on wall by the inverters. You just plug it into the 12 VDC plug in trailer and it gives you a constantly lit readout of your battery's voltage. It is so simple that it has three extra LED bulbs, green, yellow, red and as your battery voltage drops the LEDs colors give you a quick determination of battery status. Obviously, green is good, yellow is getting close and red means you require a quick recharge.. You will be amazed how slowly the voltage is reduced with LEDs as compared to an incandescent bulb.

[Joe Z]

Like John i use one of the cheapies and it works really good.... the following link is where i got mine but wal mart is the same thing.
Joe
http://www.amazon.com/Equus-3721-Battery-C...161&sr=8-29

[Wilder]

I was thinking about one of these. Has anyone tried one? It's a little more expensive ($60), but could be mounted in a visible spot and displays a lot more info.

Doc Wattson RV Battery Monitor

[Rick kl]

I use this one from Voltminder it works great, it has a low batttery alarm you can set to let you know if your battery getting low.

http://www.voltminder.com/

[Joe Z]

I was thinking about one of these. Has anyone tried one? It's a little more expensive ($60), but could be mounted in a visible spot and displays a lot more info.

Doc Wattson RV Battery Monitor

I like that meter in your link but i am only so so in the electrical department but if this item can do two things 1) Give me the amount of amps left in my battery?________ and 2)Tell me how many amps i am drawing from the battery when i have items in use?_________........ I think i would get one.
Can anyone that can read the specs on this tell me if it will do the above..... I see it has a built in shunt so i can imagine it will tell amps being used but would also like to know how many amps Ah are remaining in the battery.
Joe

[Per Walthinsen]

Joe: Xantrex Link 10. Got it from West Marine and it tells me everything I need to know. For me a volt meter leaves way too much to interpretation.

[Joe Z]

Joe: Xantrex Link 10. Got it from West Marine and it tells me everything I need to know. For me a volt meter leaves way too much to interpretation.

I'm going to google the name you mention and see what comes up..... does it tell you amps remaining in battery?_____ and amps you are currently using?______
I realise voltmeters are limited but it's better than nothing and i can be certain i am charging when plugged in or towing.
thanks,
Joe

Update: I just answered my own question and it does what i need it to do and more. Nice setup
Joe

http://www.xantrex.com/web/id/237/p/1/pt/5/product.asp

Further Update: wow that thing is expensive but i guess you get what you pay for
http://www.boatersworld.com/product/198950446.htm

[Michael Pupeza]

I'm going to google the name you mention and see what comes up..... does it tell you amps remaining in battery?_____ and amps you are currently using?______
I realise voltmeters are limited but it's better than nothing and i can be certain i am charging when plugged in or towing.
thanks,
Joe

Update: I just answered my own question and it does what i need it to do and more. Nice setup
Joe

http://www.xantrex.com/web/id/237/p/1/pt/5/product.asp

Further Update: wow that thing is expensive but i guess you get what you pay for
http://www.boatersworld.com/product/198950446.htm

Joe;
DON'T PANIC! ( from a famous SCIFI series!)
Sometimes the XantreX Link 10 and 20 come up on eBay! The older units used LEDs instead of LCDs for the display, so they are still being cleared out.
I picked up an older Link 20 New Old Stock unit at less than $150 from an eBay store that was clearing them.
This may seem expensive, but is only twice the cost of the Doc Watson. I have 2 of those types of units and they do a good job, for 1/2 of what you need to know. They measure the voltage, and discharge, but don't include the charging!
If you REALLY feel that you 'need to know', then hold out for the Link 10 or 20.
They tell you lots, maximum discharge amp hrs of your battery, charge rate, discharge time at present rate, etc.
It compensates for your discharge rate (Peukart equation) which compensates to tell you a 'true' number of minutes that you will run on your battery, at ANY rate of discharge.
In other words, its a good 'Fuel Gauge' for your battery system!
Also, I use an Intellpower PD9260 Converter from Progressive Dynamics to feed my 2 Size 27 100 AHr AGM batteries. It does spit out some interference to my Ham Radio, but not too severe!
There's LOT'S of other info on a search under my name about Converters, etc.
I do enjoy really knowing how long I can boondock without power. It also tells me if I need to run my Honda Genny for a while!
Good luck.
Mike .....>

[Scott S.]

I got a MinnKota tester from Canadian Tire. I little simpler but only $15... and it's portable

[peterh]

When I first installed my solar system I had a simple voltmeter like the one Joe Z mentioned that plugs into a cigarette lighter socket. THe numeric voltage display gives you details on your battery's voltage and the three LEDs give you a quick read as to whether your battery is close to fully charged, somewhere in the middle, or low on juice, and that plus knowing your battery's capacity is all you really need to figure out how much juice you have left. More recently I installed a digital volts/amps meter, and 95% of the time it's set to read volts, not amps. Most of the time I could care less about amps.

And it's a good thing I don't need an exact Amps reading, too, because my eBay volts/Amps meter's Amps reading fluctuates and can be off by almost 1/5 of an amp. Very frustrating, but since his replacement meter is more dependable than the other two I got from this particular eBay vendor, and because I cut the fiberglass in my trailer to fit this specific meter, I can live with it. Besides, there are really only two times I care about my Amps reading, one is to do a quick diagnostic on my solar panels to make sure they are busy charging my batteries, in which case an exact Amps reading is not too important, and the other is to see how much additional load some new 12 volt device adds to my system, so an accurately "zeroed" meter is not all that important. (I just subtract the "before" from the "after" number to get the correct number of amps.)



<=== My volts/amps meter telling me the solar panel is pumping 3.18 Amps into my battery. The actual number was 3.02 amps, but at least I knew the solar panel was working right!

[Greg A]

My thoughts are that unless you're building something like BG's Solar Desert Compact Jr that will stay off the grid for a month or better you don't need a ton of info to be mindful of your batteries condition.

I've used the $13 dollar one from Wally for 1.5 years now with a 15W briefcase solar panel and never had any need for more info on my battery.

[Joe Z]

My thoughts are that unless you're building something like BG's Solar Desert Compact Jr that will stay off the grid for a month or better you don't need a ton of info to be mindful of your batteries condition.

I've used the $13 dollar one from Wally for 1.5 years now with a 15W briefcase solar panel and never had any need for more info on my battery.

Hey Greg..... I just answered your PM. Keep all the info coming as i have alot to learn on this subject.

Mike Pupeza........thanks for all that great info and i appreciate you taking the time to explain some of the particulars to me
Joe

[D Tharp]

I did pick up a cheap one from Walmart $14.97 It has all ready anwsered some problems that I have had like my inverter is not working will post my problem with this another day.
I am have to much fun installing my new LED lights.
DAVE

[Roy Massen]

I started with a 65 watt panel and simple controller and volt meter and 2 deep cycle golfcart batteries. Since I am 100% electric (including the danfrost 12 volt fridge) I was finding I would run out of power after 2 or 3 days. So I upgraded by adding another 120 watt panel and a Morningstar Sunsaver Duo controller with the optional remote meter. It gives all kinds of info that helps me know how my system is preforming. I mount the 2 solar on the tug so I can park the trailer in the shade when it is hot and keep the panels charging. It was a bit more exensive but I was getting frustrated not knowing what was going on and guessing on how much power was left in the batteries. Now I have enough to run the fridge, lights, play the radio/cd and use my computer all I want. Well worth it.

[Capt Ron]

If you run on batteries a lot then you need to know what's going on with the charge/discharge cycles. Unfortunately it's not as simple as measuring the voltage or the amps.

Our other fiberglass camper is a boat. We have spent six months living aboard down in the Bahamas where we never plugged in. We have a single 120 watt solar panel but run the diesel engine daily to recover our 50 to 70 amp hour short-fall. Mainly we run short because we run the fridge 24/7 and with the solar panel in the dark ...

Anyway, we use a Xantrex TM500 (now called the TM500A) to measure our 220 amp hour gel cell house bank. While it gives a digital readout of voltage and amps, it accumulates the net gozinta/gozouta amp hours between charging cycles. We can see what we've used since we last ran the engine (net of the solar panel) and also see how much we've replaced while running the engine. We can also see what we're getting from the solar panel or what any given appliance is using (at that moment) by manipulating the circuit breakers.

We also run a Xantrex 1800 watt inverter that has a digital voltage display. Both the monitor and the inverter are directly feeding from the batteries on very heavy and short runs of wire yet they report different voltages. Usually the monitor reports a tenth or two under the voltage reported by the inverter. Also we have a GPS mounted on thin wire probably 20 feet from the batteries and it reports the highest voltage of the three by a tenth of a volt.(that's odd you'd think it would be the opposite). Checking these against my Fluke meter reading at the batteries reveals the monitor voltage to be the most accurate. But then it's also the most expensive instrument too.

As mentioned previously, conservation is the key. We keep the fridge as full as possible, even filling empty space with water jugs. (I know beer would work better) LED and fluorescent lights help a lot. What seems to hurt us the most after the fridge, is whether we watch a DVD on the TV in the evening or whether we use the HF/SSB radio in broadcast mode much. When sailing, the killers are the autopilot and radar. Even when sailing, we often end up running the engine just to keep up with power demands.

We're all electric on the Scamp too but we always plug-in when camped. I'd go solar on the camper except that being Florida campers, we prefer to park in the shade.

[jim munson]

I have the multimeter from Harbor Freight for $2.99.
Cut off the leads drill a little hole and stick it on with velcro.
Set it on 20 and there's your voltage.
KSS

[Rick kl]

I have been using the voltminder all summer, it has performed excellent $30