LED METER INSTALL

[Borrego60]

Here is a neat little idea. Ever wonder what your solar panel is putting out power wise and see what the voltage state of your battery is, that is if your controller is not digital meaning no meter. I installed a digital panel mount volt meter this weekend and it works great. I hook this up before the solar panel controller and then ran a wire to the + side of the fuse box from the battery. The switch is wired so that in the down position it will read the voltage that the solar panel is sending to the controller. In the up position it tells me the voltage of the battery. I got tired of breaking out a volt meter to check on both of the items so I thought this was a neat add on to the trailer. The meter can be seen from a good distance and is nice and bright.

I measured the meter about 100 times and then transfered the measurments to the trailer. I used masking tape to cover the work area and sealed off the inside of the nose box so metal filings and such would not fall inside and rust if I could not get them out. Drilled 4 holes 1 in each corner and used a good jig saw bit and cut out the rest of the material. Took my time about 40min to do the cutting. I cut and filed the metal down so the meter fit snug in the square hole I then painted the bare metal. Sealed up the front glass with marine sealant so water can not enter, before seating the meter I layed down a nice thick bead all the way around the meter to seal it. I pushed the meter home tight and wiped off the excess sealant, thank God for the masking tape which was removed after the sealant was wiped clean.


I wired up the meter and it works great. I am still waiting for my water proof switch in the mail, the one I installed is a temp to see how the set up would work and it works great. The switch I am waiting for has this configureration ON OFF ON this way you can turn the meter off if not needed.

 

[FredB]

Thanks for reminding me. I have one to install. The dual input with the off position is a good idea.

 

[Joe917]

A voltmeter is nice but an amp hour meter is the only way to accurately assess battery state of charge. Add a Trimeric.

 

[Borrego60]

The new switch will have the center as the off position. The meter was picked up from Amazon SMAKN 2 Wire Green Dc 4.0-30v LED Panel Digital Display Voltage Meter Voltmeter

 

[Borrego60]

A voltmeter is nice but an amp hour meter is the only way to accurately assess battery state of charge. Add a Trimeric.

Might want to double check what a Trimeric is.

 

[Team Ball's Out]

I got the pop corn!

 

[Weasel with a Diesel]

Here is what I use to check voltage, current, charge and discharge, remaining runtime of the supply battery:
consumes about 1.5mA

It's little bit huge 4"x4" but well visible from distance, with night illum, low battery alarm and all the bells...
You simply enter the battery capacity, set the ambient temperature and put a load on it. voila, the remaining charge shows up.

 

[pugslyyy]

A voltmeter is nice but an amp hour meter is the only way to accurately assess battery state of charge. Add a Trimeric.

I guess it all comes down to the complexity that you want. I find myself looking at my volt meter to assess state of charge more often than anything else. It might not be exact but it is close enough.

 

[Joe917]

FYI : a voltmeter gives actual battery voltage now. The problem is if have just charged or discharged the voltage will not be stable. The batteries plates take time to react with the electrolyte. For the voltage meter to give an accurate indication of battery charge you need to let the battery rest for several hours. Impractical. An amp meter uses a shunt on the negative side of the battery and measures every amp in and out. once programmed with the battery bank capacity and allowing for system inefficiency the meter will give a very accurate state of charge. For a full timer system it is essential. For a weekender where you want to check the batteries before you head out a voltage meter is fine. Its all needs vs cost. By the way, nice clean install.

 

[pugslyyy]

FYI : a voltmeter gives actual battery voltage now. The problem is if have just charged or discharged the voltage will not be stable. The batteries plates take time to react with the electrolyte. For the voltage meter to give an accurate indication of battery charge you need to let the battery rest for several hours. Impractical. An amp meter uses a shunt on the negative side of the battery and measures every amp in and out. once programmed with the battery bank capacity and allowing for system inefficiency the meter will give a very accurate state of charge. For a full timer system it is essential. For a weekender where you want to check the batteries before you head out a voltage meter is fine. Its all needs vs cost. By the way, nice clean install.

It's possible to be as complicated as you want. I still maintain that a quick check of open circuit voltage is easy and useful. Watching what happens as you load the battery down also gives a good indication of how much of a draw you are putting on the battery.

 

[skersfan]

I use a Morningstar 15 amp digital display.

It controls my battery charge, tells me the usage/draw and the state of the battery. Runs about 120 bucks on line. But it needs to be inside. It runs continuously, but you can shut the load off. Mine has been in the garage now for over 3 months and the state nor the charge has dropped. So it does not draw much. I use these in over 20 solar micro wave towers, never had one fail in 12 years, and have had some batteries on them for that long. Great product and very reasonable.
http://www.infinigi.com/morningstar-ps15-prostar-15-charge-controller-p-822.html

 

[Borrego60]

Thank you for the coment, Its all needs vs cost. By the way, nice clean install.
I do have a Go Solar 30 amp charger that will check everything at the push of a button, I really did not want to cut a large mounting hole in the nose box. So I put this gem in a waterproof Pelican box. I have input and output plugs dummy proof. This way it is protable and I can charge up my truck if it goes dead. I had been using this for a while and it works just fine. The trailer has a solar charger in it that I just plug the panel in and away it goes. I just wanted something to shows volts in and what the battery voltage is. The one in the pelican case is a charger amp meter ect tells me all I want to know. Here are a few pictures of that unit. That morning star unit is nice.

 

[skersfan]

Morningstar is a main stay in solar power, have been around a long time. Verizon uses them in their solar cell sites, SoCal Edison uses them in some of theirs, of course the larger industrial type. Outback makes a quality controller too, but is just too large for trailer application.

I am building a new solar tower using the new tristar system, 12/24/36. It has a 77/39 inch panel that develops 300 watt. Just too big for a trailer, but man it would end any battery storage problems for sure

 

[Weasel with a Diesel]

Love the peli box install! The battery monitor is so far the best investment to keep the expensive batteries alive. I didn't install the monitor- to be honest I havn't found a nice place for it so far. It is- to big. I do plan to exchange it into a smaller version.

 

[Weasel with a Diesel]

I just wanted to show a case when a voltage meter isn't a reliable indicator:

As you can see the voltage reading is about 12.3V, which is indicating 50% SOC with an AGM battery.
The battery monitor indicates 80% SOC on the bargraph on the right side. Reason for this voltage drop is the momentary current discharge of 11.6A- the coolant engine heater has just started to run!

20% difference depending on your battery capacity is a lot!