DC 4-40V LED Digital Voltmeter

The DC 4-40V LED Digital Voltmeter is a compact panel-mount voltage display that connects across the voltage source it measures using just two wires positive and negative and powers itself from that same source while showing the reading on its LED display. No third wire, no separate power supply, no additional components between the voltmeter and the source. Two wires across the circuit node being measured is all the installation requires.

The mini voltmeter 4V to 40V measurement range covers the most common DC supply voltages used in electronics and battery 5V USB supplies, 9V battery, 12V solar and automotive systems, 24V industrial panel supplies, and 36V e-bike battery systems all fall within this single range without needing a different voltmeter for each voltage level. Input impedance above 100KΩ means the digital dc voltmeter draws negligible current from the measured circuit at 12V and 100KΩ the voltmeter draws only 0.12mA from the source being measured, which is below what most circuits would register as a load.

The 300ms refresh rate updates the display approximately every 0.3 seconds fast enough to track voltage changes from battery discharge, load switching and charger output variation in real time. At under 23mA operating current the mini dc digital voltmeter draws its own supply from the measured circuit, this is the same current the LED display digits consume. That means the voltmeter needs a source capable of supplying at least 23mA alongside whatever load is already connected. On most battery and power supply that is negligible headroom. The digital voltmeter suits battery monitor panels, solar station displays and power supply output monitoring. This module is working on voltage monitoring and panel instrument. Available on StemVolt.

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• Checkout Digital LED DC Voltmeter Ammeter

Features:

• 4V to 40V range covers single-cell Li-Ion through 36V e-bike battery systems
• 2-wire self-powered eliminates separate power supply wiring for the module
• 100KΩ+ input impedance keeps dc 4-40v LED digital voltmeter load below 0.12mA at 12V input
• 300ms refresh updates reading three times per second for live monitoring
• Under 23mA draw stays negligible across most battery and panel circuit

Technical specifications:

 Applications:

• DC 4-40V LED digital voltmeter monitors 12V solar battery bank voltage on off-grid panel
• Digital voltmeter displays live voltage on DIY bench power supply front panel output
• Mini voltmeter shows battery pack discharge voltage on robot chassis status panel
• LED digital voltmeter monitors 24V industrial panel supply rail in control cabinet
• 4V mini digital voltmeter tracks 5V USB supply rail voltage on development bench

Package includes:

• 1 x DC 4-40V LED Digital Voltmeter