Summary of Battery voltage monitor
This article describes a DIY voltage monitor project designed to remotely display battery voltage for off-grid renewable systems, caravans, boats, and cars. The device plugs into a car's 'cigar lighter' socket and features a remote LED display for easy monitoring and maintenance of lead-acid batteries.
Parts used in the Battery Voltage Monitor:
- 3mm plywood sheet (around 1/3 sheet of A4)
- Wood glue
- 2 x M3 machine screws (around 12mm long)
- 2 x M3 nuts
- 4-digit LED display
- On/off switch
- 2m of twin (red/black) cable
- 'Cigar ligher' type plug
This voltage monitor has been designed to remotely display battery voltage so that people monitor and maintain their batteries easily. It was designed for use on off-grid reneable energy systems (such as my solar PV system), but it would also be useful to anyone who has a lead-acid battery, such as caravans, boats and cars.
It is designed to plug in to a car ‘cigar lighter’ socket and display the voltage on a remote LED display. Here are the plans to make your own.
Parts required
- 3mm plywood sheet (around 1/3 sheet of A4)
- Wood glue
- 2 x M3 machine screws (around 12mm long)
- 2 x M3 nuts
- 4-digit LED display
- I used this one from SunTekStore (but available at other places including eBay):
- http://www.suntekstore.co.uk/product-14002344-036inch_4_digit_digital_panel_voltmeter_0-33v_red_led_voltmeter.html
- On/off switch
- I used this one from SunTekStore (but any switch would work):
- http://www.suntekstore.co.uk/product-14001517-black_mini_size_spdt_slide_switch.html
- 2m of twin (red/black) cable
- ‘Cigar ligher’ type plug
For more detail: Battery voltage monitor
- What is the primary purpose of this voltage monitor?
To remotely display battery voltage so people can monitor and maintain their batteries easily. - Can this device be used on off-grid renewable energy systems?
Yes, it was specifically designed for use on off-grid renewable energy systems like solar PV systems. - Does this project work with lead-acid batteries found in cars?
Yes, it is useful for anyone who has a lead-acid battery such as those in caravans, boats, and cars. - How does the device connect to the power source?
It is designed to plug in to a car cigar lighter socket. - What type of display does the project use?
The project uses a 4-digit LED display to show the voltage. - Is the specific switch from SunTekStore required for the build?
No, any switch would work, though the author used one from SunTekStore. - What materials are needed to construct the case?
A 3mm plywood sheet and wood glue are required to make the case. - How much twin cable is needed for the wiring?
You need 2m of twin red and black cable.
