A voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit. Analog voltmeters move a pointer across a scale in proportion to the voltage of the circuit; digital voltmeters give a numerical display of voltage by use of an analog to digital converter.

Specifications:

• Detection voltage: DC 2.4V ~ 30V
• Working current: andlt;30mA
• Display: 0.28 inch LED
• Dimensions: 31 X 12.0 X 9mm (length x width x height)
• Installation hole: 23 X 10 mm
• Measurement rate: ?200mS / times
• Accuracy: 3%(+/- 1 word)
• Operating temperature: -10 ~ +65 º
• Working humidity: 10~80%
• Working pressure: 80~106kpa
• Color: 
  This package includes 5 colors Mini Digital DC Voltmeter :
  Red: 2.5V - 30V
  Yellow: 2.6V - 30V
  Green: 2.6V - 30V
  Blue: 3.2V - 30V
  White: 3.0V - 30V