ArkansasDon
Adventurist
any suggestion on what is a good long lasting gauge. My battery tongue box will house 2 6V Trojan golf cart batteries wired to 12v.
12v battery Indicator gauge
- Thread starter ArkansasDon
- Start date
glamisdude
Adventurist
I bought this one a few months back for my trailer and it has been working well for me. I like that it cycles back and fourth between voltage and % charged as well as displaying a level indication. Obviously from China but quality is surprisingly good, also can't beat the price.
https://www.wish.com/c/55f276b65d444b109fac4e28
https://www.wish.com/c/55f276b65d444b109fac4e28
The thing about most battery gauges are that they often only use voltage as their metric for measuring capacity. This can give an idea of current output, but does little to tell you anything of battery health or actual capacity (amp hours). IMO, unless it does more than merely display current voltage, it really isn't worth much. My answer when I was building my system was the Xantrex LinkPRO, but as most things coming from the marine industry, it was anything but cheap. That said, it's been working great now for about 5-6 years.
ArkansasDon
Adventurist
my batteries will be 6 volt golf cart batteries x2 wired to 12v which gives me 224ah. My tongue box (houses my electrical) will have 30amp solar charge controller wired with 1 permanent 100watt Renogy solar panel on the tent rack, 1 Renogy 100watt suit case portable which will give me 200watts, 3 12v socket outlets, 1 10watt 12v LED flood light, various fuses for the solar system. The accessories will be 1 22qt Engel fridg \ freez draws around 1 to 2 amps per hour, MightyKool MK portable A\C which draws .08 to 2 amp per hour.
For traditional meters, like the one that glamisdude linked to, and the ones that mark mentioned; it's true, they only tell you the voltage at the moment.
The other part to that story is that unless you put it on a momentary switch, activating it only when you want to see the voltage, keeping it on all the time consumes battery life just to tell you the voltage. In other words, they're a net loss, and they've really told you nothing about the State of Charge/Battery Health.
Things have come along a bit since Mark's build, CTEK now makes a device called the Battery Sense, it shows you current voltage AND battery health via Bluetooth to your smartphone on an app. It uses a millivolt to operate, and also keeps a running chart of your battery health, which means you could track dips in voltage by the day.
I just happen to sell these on my website!
I use this on my vehicle, and it's pretty nice sitting in camp knowing I don't have to keep an eye on a meter. My phone will pop up a notification if the battery needs attention.
The other part to that story is that unless you put it on a momentary switch, activating it only when you want to see the voltage, keeping it on all the time consumes battery life just to tell you the voltage. In other words, they're a net loss, and they've really told you nothing about the State of Charge/Battery Health.
Things have come along a bit since Mark's build, CTEK now makes a device called the Battery Sense, it shows you current voltage AND battery health via Bluetooth to your smartphone on an app. It uses a millivolt to operate, and also keeps a running chart of your battery health, which means you could track dips in voltage by the day.
I just happen to sell these on my website!
I use this on my vehicle, and it's pretty nice sitting in camp knowing I don't have to keep an eye on a meter. My phone will pop up a notification if the battery needs attention.
Ok... with the 200 Watts of solar, and 224 amp hours of batteries, the battery condition is probably of little concern. I probably wouldn't bother with a meter at all.
Alternatively, now that your phone is part of the tool set your vehicle uses, you're less likely to leave it behind, just like everyone else who's phone is practially implanted
Alternatively, now that your phone is part of the tool set your vehicle uses, you're less likely to leave it behind, just like everyone else who's phone is practially implanted
ArkansasDon
Adventurist
phone, my cell is the least of my concerns to life.
Herbie
Adventurist
While it's true that the inexpensive panel meters do consume power while they're running, it's important to note that they do it to the tune of about 10mA +/- 5. In other words, at worst case it draws about as much as having a USB charger installed (or plugged into a cigarette plug) without a phone connected to it. This is also on the same magnitude as the "dark current" draw of your ECU or radio which consume a certain amount of power at all times.
Mine is on a momentary switch so I can toggle back and forth between the battery voltage and solar input voltage, but I leave it switched to the battery display for weeks at a time with no ill effects.
Do these display amperage and test the battery with a shunt like the LinkPRO? All is see is voltage via a graph. Also parasitic draw is published as 9mA on the LinkPRO.
No, they connect directly to the battery and test the battery from there. These are not current meters. Simply State of Charge meters showing voltage and capacity. You're not seeing voltage via the graph, that indicates capacity.
9mA was enough to take out your aux battery at Expo if I recall correctly, causing you acquire a solar setup at the show.
Is trending voltage a measure of capacity? I always understood battery capacity to be measured in amp hours. Back at that Overland Expo we were spit-balling what could have flattened my battery, but after years of use now I haven't experienced anything that would lead me to believe that the LinkPRO was the source.
ArkansasDon
Adventurist
Curious Mitch or any one, I'm trying to understand this electrical thing were I am not knowledgeable. I planning on using 2 6v golf cart batteries Trojans wired in series to 12v which will give me 224ah, but I found a battery manufacture VMax Charge Tanks which are AGM batteries 155ah. The golf cart batteries life span range 3 to 5 yrs, these VMax AGM have 10 to 12 yrs span. Both are about the same cost.........My question is years of use vs. ah? which would you suggest? My set up for my trailer would be 1 permanent 100watt Renogy solar panel on the tent rack, 1 Renogy 100watt suit case portable which will give me 200watts, 3 12v socket outlets, 1 10watt 12v LED flood light draws around .08 amps per hour, the accessories will be 1 22qt Engel fridg \ freez draws around 1 to 2 amps per hour, MightyKool MK portable A\C which draws .08 to 2 amp per hour.
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You're missing the key, the Battery Sense, when installed is made aware of the battery's capacity in Amp Hours, and it's somehow measuring this. I say somehow, because they won't tell me how, and I've talked to some pretty high up folks with CTEK, including their engineer in Sweden. The graph is a measurement of Amp Hours, not voltage. You can watch the process in the app while the engine is running. While voltage and state of charge are connected, you don't see the percentage change until the storage capacity is refilled, regardless of what voltage is showing.
State of charge meters are all estimates at best. Battery voltage under load will tell you as much as you really need to know.
See, that's the thing... There wasn't anything to miss. Their info on the website is embarrassingly light. So, in the end it seems that it's a shunt that reports status via bluetooth and app.
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Mitch,
Your link in post #5 I just happen to sell these on my website!
Does not point to the CTX Battery Sense.
Do you still sell these?
Your link in post #5 I just happen to sell these on my website!
Does not point to the CTX Battery Sense.
Do you still sell these?
Yes, I can still get them. I had to remove the store from my site. The cost of the shopping cart feature from my host way exceeded its return.
(BTW, please remember to tag me (using the @username feature) or reply to a post quoting my original, so that I get an alert that you posted, like the one you just got)
Code Red
Adventurist
I've got a couple of the CTEK units, and I am not impressed. They don't have a shunt, and so they can't count amps in or out. They sense voltage and temperature, and then they guess. There is some logic to it, but none that makes any reliable sense.
Last week mine showed 79% on my drive to work. Then after 10 hours in the parking deck showed 89%. It jumps 10-15% in one direction or the other overnight or during the day several times a week with no load. It's equally likely to jump up as it is down. I have also gotten in the truck on a 50* morning and had it indicate 12.7 volts and tell me I was at 70% capacity. It simply cannot be correct. Either the CTEK programming is wrong, or there is a phantom battery charger stalking our trucks.
The one on my wife's truck does the same thing.
I like the ability to get voltage and temp remotely, but I have zero faith in what it is telling me about capacity. I generally just use one of those charts that correlate resting voltage and temp to State of Charge. If its 70* and I'm showing 12.7 volts after knocking off the surface charge then I'm happy. If its 70* and I'm showing 11.5 then I'm not. If the fridge has been running for a few hours and I'm showing 12.5 volts then I'm content. I essentially use the CTEK as a remote volt meter.
Last week mine showed 79% on my drive to work. Then after 10 hours in the parking deck showed 89%. It jumps 10-15% in one direction or the other overnight or during the day several times a week with no load. It's equally likely to jump up as it is down. I have also gotten in the truck on a 50* morning and had it indicate 12.7 volts and tell me I was at 70% capacity. It simply cannot be correct. Either the CTEK programming is wrong, or there is a phantom battery charger stalking our trucks.
The one on my wife's truck does the same thing.
I like the ability to get voltage and temp remotely, but I have zero faith in what it is telling me about capacity. I generally just use one of those charts that correlate resting voltage and temp to State of Charge. If its 70* and I'm showing 12.7 volts after knocking off the surface charge then I'm happy. If its 70* and I'm showing 11.5 then I'm not. If the fridge has been running for a few hours and I'm showing 12.5 volts then I'm content. I essentially use the CTEK as a remote volt meter.