Checking Coach Voltage on the Cheap

[alparmer]

Not sure if your batteries are being charged. The dummy lights only tell you how much charge there is in the battery, but it won't tell you if they are actually being charged by the engine, shore power, or generator. Install this into your house 12v cigarette lighter and monitor from inside.

Just remember that a fully charged battery is ~12.6v.
Can't beat it for 6 bucks:

12V 24V LED Car Auto Vehicle Cigarette Lighter Smoking Voltage Gauge Volt Meter | eBay

[cjd10]

Have you seen the "remote pendant" that plugs into the converter that shows the status?

Converter Status Remote Pendant

Been meaning to ask if anyone got one with their MH. It looks like it comes with the converter if you buy it but you can order one for $10.95. Would be nice if it actually did work remotely but still been thinking about ordering one

[alparmer]

I'd have to look, but I believe our converters include the charge wizard. It would be nice to have the pendant, but not sure it's worth the install. It looks like it has a ribbon cable that has to be routed from the converter way in the back to wherever you want to install the pendant. I think it will be redundant with the charge wizard running.

[TURBS]

Originally Posted by cjd10

Have you seen the "remote pendant" that plugs into the converter that shows the status?

Converter Status Remote Pendant

Been meaning to ask if anyone got one with their MH. It looks like it comes with the converter if you buy it but you can order one for $10.95. Would be nice if it actually did work remotely but still been thinking about ordering one

Pendant doesn't give any kind of voltage reading.

TURBS

dog wisperer

[Herk7769]

Originally Posted by alparmmer

Not sure if your batteries are being charged. The dummy lights only tell you how much charge there is in the battery, but it won't tell you if they are actually being charged by the engine, shore power, or generator. Install this into your house 12v cigarette lighter and monitor from inside.

Just remember that a fully charged battery is ~12.6v.
Can't beat it for 6 bucks:

12V 24V LED Car Auto Vehicle Cigarette Lighter Smoking Voltage Gauge Volt Meter | eBay

Any device that measures voltage that connects to wiring inside the camper (and not to the terminals of the battery) will only tell you the voltage is available IN the camper; NOT at the battery.

Just because there is 13+ volts in the camper does not mean the battery is "seeing" it. There are two inline fuses between the battery and the camper's 12 volt wiring, either one of which can be "open" and prevent the battery from charging; yet show 13+ volts inside (when on external - shore - power).

Fuse one - protects the battery and is located right AT the battery. If this is open everything works in the camper (including slides and stabilizers) when on external power, there is 13+ volts on the camper, and yet the battery will not charge.

Fuse two - protects the camper from the tow vehicle's charging circuit and is located near the pigtail junction box. If this is open (and you are on shore power), everything works inside at 13+ volts BUT the main slides, power stabilizers/jacks, and power tongue jack (if equipped) will not and the battery will not charge.

[alparmer]

Hey, for 6 bucks is better than nothing. I understand what you are saying, but it would be a PITA to hook it up directly to the battery terminals. Besides, when the engine is off and there is no shore power you can see the live status of your battery.

[Herk7769]

Originally Posted by alparmmer

Hey, for 6 bucks is better than nothing. I understand what you are saying, but it would be a PITA to hook it up directly to the battery terminals. Besides, when the engine is off and there is no shore power you can see the live status of your battery.

Agreed.

Just so everyone knows that the voltmeter will only show voltage being supplied to the camper and not, necessarily, the battery.

[bubbles]

Appears that you have something going here. Your awning power is supplied to the awning switch directly via a 15 amp fuse connected to the battery. I believe the switch is located by the entrance on your unit. There is enough space on the switch panel to mount your indicator and it would be readily viewable from anywhere within the coach forward end. It could be tapped off the awning 12v feed at the switch and a ground anywhere within easy reach with no degridation in awning performance. It would also be fuse protected (15A) and the awning switch could provide a test in case the indicator was blank. Just a thought. 02 alarm feed from battery is also there protected by a 5A fuse. Step power is there protected by a 20A fuse. Outside light also there. All this of course is predicated on the preceeding switches located at the entrance where mine is located.

[alparmer]

That would be a great spot for it. Something to tinker with once it warm up a bit.

[Iggy]

The only way to see actually battery voltage is to disconnect shore power, no generator and have the gauge hooked up to the batteries.
Then you will see if your batteries are holding a good charge or not.

[mbtelguy]

Iggy, true as long as the engine is not running

[alparmer]

That was already stated: "Besides, when the engine is off and there is no shore power you can see the live status of your battery."

I'm not worried about voltage drop from the battery to the cigarette lighter. Went out and measured at the battery and it's pretty darn close to the reading on the cigarette lighter. I'm not looking for perfect science here, just a quick way to determine what's going on with the batteries especially if you are boondocking.

It came in pretty handy on our pontoon boat. We would be in the middle of the lake having a good time and every once in a while I would look at the meter to make sure I had enough power to start the engine.

This was really meant for folks that don't have a clue where to start looking at battery problems. Not everyone knows what a multimeter is and how to use it. If you plug the meter to your cigarette lighter and it reads out 12v you'll know you are pretty close to having a discharged battery.

Ideally: Hook up the meter directly to the battery, check the batteries with a load tester and a hydrometer.

Don't forget the principle K.I.S.S.

[mbtelguy]

alparmmer, we have gone from “are your batteries charging ?” to “are your batteries charged ?” I think these are two different questions.

I think Herk was right on when he identified situations, that using a meter as suggested could be misleading.

As far as the engine running, I was simply adding to Iggy’s list.

Gary

[alparmer]

Agree, the title is misleading. Could one of the moderators please change it to "An inexpensive way to check the charge/battery voltage in your coach", or something similar.

I still don't see how the meter's reading cold be misleading though. If you start your engine you will see a voltage increase letting the user know that there is a charge present. Whether it reaches the battery or not it's a different story. Same thing with shore power. You will know if the battery is being charged from the reading it shows before and after. It works for me. If I see something wrong with the numbers then I'll start troubleshooting.

[Herk7769]

Originally Posted by alparmmer

Could one of the moderators please change it to "An inexpensive way to check the charge/battery voltage in your coach", or something similar

Done

[alparmer]

Awesome, thanks.

[Iggy]

I'm considering buying the digital volt gauge for my house batteries like the one in message #1 but hook directly up to my house batteries with a switch to turn it on and off.
Thanks.

[alparmer]

They are cheap enough that you could also put one in the battery bay. You could even put one on each battery to monitor each one individually.

[MrJoe]

Just ordered the lighter type for a little over 3 bucks on Amazon. Silly cheap...