Where to tap DC power for small Volt meter in control center

[Chiefblueman]

In the case of my trailer, I'm simply taking a reading at the end of 2-#6 wires connected directly to the battery terminals and the output of the converter ahead of loads. Each load imposed is reflected in the voltage reading at the meter and is also reflected in measurements taken at the battery terminals. I see no reason to run more wiring to the battery for a simple volt meter. I have verified the accuracy of the remote meter by taking readings at the battery terminals under no load and small load conditions at the same time. I can see converter output voltage and battery voltage, loads connected or disconnected. It's a handy tool as I use it. It's a simple matter to switch off the converter, switch on the batts and check their voltage after sitting disconnected for weeks or even months. BTW, my disconnect is wired as a true disconnect.

[Chiefblueman]

My short run I used 16 Guage I believe. ....was about 6". If I go down to circuit panel, should I step up thickness? It will be @ 5 ft.
What Guage then?

The #16 should be fine, Jim. #16 is good for far more than the meter needs in 5 ft.

[Jims94vmx]

Really ran wires down to circuit panel and onto the terminal blocks feeding the load.....

[powerscol]

Hold on one second. There always should be a fuse in line. The way you wired it it appears it is not fused. If a short occurs in the line its toast and so could be the trailer.

In post #1 I would have tied into the awning switch positive side. Also the reason it went off with the ceiling light on is in my unit that is a 3 way switch (two switches operate the same lights)

Just trying to be safe

[Jims94vmx]

Hold on one second. There always should be a fuse in line. The way you wired it it appears it is not fused. If a short occurs in the line its toast and so could be the trailer.

In post #1 I would have tied into the awning switch positive side. Also the reason it went off with the ceiling light on is in my unit that is a 3 way switch (two switches operate the same lights)

Just trying to be safe

Should I use one of the fuses terminal block then?

[powerscol]

Should I use one of the fuses terminal block then?

That should work - is there a spare slot available on the panel. Should not need much - possible 5 amp.

[Jims94vmx]

Took your advise. Wire run to unused (fuse)spot, thanks. Safety 1st.....glad I did a followup

[Jerryr]

My short run I used 16 Gauge I believe. ....was about 6". If I go down to circuit panel, should I step up thickness? It will be @ 5 ft.
What Guage then?

There is VERY Little current draw from the meter so wire gauge should not be an issue.

EDITED after realizing Jim and Belinda H. Pa. used an free fuse location. 16 Gauge should handle up to 12 amps or so. The fuse is there to protect a shorted wire. I would use the smallest fuse needed to power the meter. a 1 amp fuse should be more than enough.

[jkwilson]

In the case of my trailer, I'm simply taking a reading at the end of 2-#6 wires connected directly to the battery terminals and the output of the converter ahead of loads. Each load imposed is reflected in the voltage reading at the meter and is also reflected in measurements taken at the battery terminals. I see no reason to run more wiring to the battery for a simple volt meter. I have verified the accuracy of the remote meter by taking readings at the battery terminals under no load and small load conditions at the same time. I can see converter output voltage and battery voltage, loads connected or disconnected. It's a handy tool as I use it. It's a simple matter to switch off the converter, switch on the batts and check their voltage after sitting disconnected for weeks or even months. BTW, my disconnect is wired as a true disconnect.

You still get voltage error caused by resistance of the wire whether you connect before or after the loads. The problem comes from the length of wire before your voltage measuring device connection. 6AWG has about .4 Ohms per 1000ft. If you are 10ft from the battery drawing 20A your error will be 0.16V.

[Jims94vmx]

Measuring from Solar Leads and also from the inverter matched each other....i have about a .1 loss at the meter.....

I ran a test today to make sure we would be okay overnight with a sound machine and having coffee....

Ran sound machine all 9 hours (.5 watts)
made coffee half hour (820 watts)
wife used curling iron (?) for about 10 minutes
fridge fans on back of fridge cycling on (?) was hot out today
Charged Galaxy S Tablet

Ended up at 12.2 amps......

Fridge was on propane, water heater off, converter off......