These 0.36" voltmeters can measure up to 50VDC as they have a separate power supply wire and a common ground. You can use them in two ways:
If you connect the positive supply terminal and the voltage sense terminal together, you have a meter that will measure up to 30 volts DC and which is powered from the voltage to be measured, so needs no extra power supply.
If you want to measure the full voltage range of 0-50V, then you power the meter via the supply terminals (the supply can be from 4 to 30V) and feed the voltage to be measured into the sense terminal.
But, unlike my other panel meters, these have under voltage and over voltage LEDs and control outputs, so you can use these for tasks such as battery protection or charging, or anywhere you need to control something based on voltage.
The supplier of these doesn't supply a datasheet, but they are fairly simple to work out. To program the setpoints, just press both buttons together and then press them individually to set the voltage. Press them together again to move to the other setpoint.
The red LED indicates overvoltage and the yellow one undervoltage. Under and over voltage outputs appear on the row of 5 solder pads at the bottom, along with a ground terminal and the two switch terminals, so external switches can be used. The power and sense terminals are the 4 solder pads on the right hand end of the display.
These are ideal as battery monitors or anywhere you need a small panel meter.
Specifications:
Dimensions: approx 29mm x 23mm x 10mm high
Measuring range: 0-50V DC
Display: 0.36 inch (9mm) three digit with auto-shifting decimal
Resolution: 0.05V
Refresh rate: 300ms
Minimum input: 0V DC
Maximum input: 50V DC
Power supply: 4-30V DC
Working temperature: -40 to 85°C
Polarity protection: On power supply inputs, not on sense input.
This product was added to our catalog on Friday 14 March, 2014.
