Forum Discussion

IBcarguy's avatar
IBcarguy
Explorer
May 29, 2016

12V meter and receptacle

I just installed a 12V lighter receptacle with a volt meter in my entertainment center. I wired it with a switch so the digital meter doesn't run constantly. It's wired so that when shore power is hooked up, I can monitor the inverter/charger rate to the batteries. When the shore power isn't hooked up it simply reads battery voltage. This project only cost about $16 in materials and to me, it's a very useful add-on.


  • The switch was installed to simply kill the digital meter so it's not illuminated 24/7. I know it doesn't draw much but I thought it couldn't hurt.
  • I have three of these installed in my 5th wheel but I don't see any need for the switch. I also have the USB.
  • dewey02 wrote:
    I was thinking of doing something similar. How did you wire it to measure inverter/charger rate when on shore power?

    Actually this happened by accident. I pulled power from the hot side of a "battery disconnect" switch on the accessory switch panel on the other side of the entertainment center. The inverter is wired into the 12v system so whenever shore power is plugged in, it will read the voltage that is being pushed in to the batteries from the inverter/charger. With the shore power unplugged, it just reads whatever volts the batteries have. When I think about it, this would probably occur no matter where I picked up the power.
  • I have no need for another plug in 12 volt as my 800 watt inverter with USB plugs is installed. I bought a voltmeter with two decimal places from China for about $3.50 and it runs full time behind the breaker panel door.
  • RoyB's avatar
    RoyB
    Explorer II
    I just purchased the same panel from AMAZON but I included the two USB charger modules...

    The round modules rotate so you can have your panel horizontal or vertical...

    These are made by BLUE SEA which are known for their quality and durability...



    I also purchased one of these Equus Innova 3721 Battery and Charging System Monitor from AMAZON that plugs into a regular 12V SOCKET like in your truck. My truck does not 12VDC VOLTMETER which is great to have to watch battery and alternator performance.



    Roy Ken
  • I was thinking of doing something similar. How did you wire it to measure inverter/charger rate when on shore power?
  • found it on amazon:
    http://www.amazon.com/niceEshop-Marine-Cigarette-Lighter-Voltmeter/dp/B016OFBM3I/ref=sr_1_101?ie=UTF8&qid=1464549132&sr=8-101&keywords=cigarette+lighter+meter
  • Nice. :C
    Do you have a link for the receptacle/voltage meter?