Multimeter Simulator Online

Interactive digital multimeter simulator for learning electrical measurements. Practice measuring voltage, current, resistance, continuity, and testing diodes.

0.000
V DC
Voltage Measurement
BAT: OK
HOLD: OFF
AUTO
Measurement Mode
Range / Settings
Additional Settings
Red Probe (Positive)
VΩmA
Not connected
Black Probe (Negative)
COM
Not connected

How to connect probes: Click on the red dots in the circuit diagram to connect the multimeter probes. Red probe connects to positive/input points, black probe to negative/common points.

Probes are automatically connected when the simulator starts. Click on different points to change connections.

Test Circuit
Click on measurement points (red dots) to connect probes
Measurement Analysis

Understanding Multimeter Functions

A digital multimeter (DMM) is an electronic measuring instrument that combines several measurement functions in one unit. It can measure voltage, current, resistance, and other electrical parameters.

Voltage Measurement (V)
Measures electrical potential difference between two points in a circuit. Can measure DC (direct current) and AC (alternating current) voltage.
Current Measurement (A)
Measures the flow of electric charge in a circuit. Must be connected in series with the circuit. Can measure DC and AC current.
Resistance Measurement (Ω)
Measures how much a material opposes the flow of electric current. Circuit must be powered off and component isolated for accurate measurement.
Continuity Test
Checks if there is a complete path for current to flow (typically beeps if resistance is below 10-50Ω). Useful for checking fuses, wires, and connections.
Diode Test
Checks the forward voltage drop across a diode. A good silicon diode typically shows 0.5-0.8V in forward bias and OL (open line) in reverse bias.

How to Use This Simulator

1

Select Measurement Mode: Choose what you want to measure (voltage, current, resistance, continuity, or diode test).

2

Select Range: Choose the appropriate measurement range. Use auto-range for automatic range selection.

3

Connect Probes: Click on the red dots in the circuit diagram to connect the multimeter probes to measurement points.

4

Simulate Measurement: Click the "Simulate Measurement" button to see the measurement result on the multimeter display.

5

Analyze Results: Read the measurement value and interpretation in the results section.

Probe Connection Guide:

  • Black Probe: Always connects to COM (common) terminal
  • Red Probe: Connects to VΩmA for voltage, resistance, and small current measurements
  • For Current > 200mA: Red probe should be moved to 10A terminal (not simulated here)

Safety Warning: When using a real multimeter, always:

  • Start with the highest range when measuring unknown values
  • Never measure current in parallel with a circuit (always in series)
  • Ensure the circuit is powered off when measuring resistance
  • Use appropriate personal protective equipment when working with high voltage

Common Multimeter Symbols and Abbreviations

Symbol Meaning Description
V Volts Unit of electrical potential
A Amperes Unit of electrical current
Ω Ohms Unit of electrical resistance
DC or ⎓ Direct Current Current flowing in one direction
AC or ~ Alternating Current Current that changes direction periodically
mV, mA Millivolts, Milliamps 1/1000 of a volt or amp
OL Overload or Open Line Measurement exceeds range or circuit is open
Continuity (sound wave symbol) Continuity Test Audible beep indicates complete circuit

Frequently Asked Questions

Voltage is measured in parallel across two points in a circuit (like measuring pressure in a pipe). Current is measured in series with the circuit (like measuring flow rate through a pipe). For voltage measurement, the multimeter has very high resistance to avoid affecting the circuit. For current measurement, the multimeter has very low resistance to avoid restricting current flow.

"OL" stands for "Overload" or "Open Line". It means the resistance is higher than the selected range can measure, or there is no connection (infinite resistance). Try selecting a higher resistance range, or check if your probes are properly connected to the component.

To measure current: 1) Turn off power to the circuit, 2) Break the circuit at the point where you want to measure current, 3) Connect the multimeter in series (so current flows through the meter), 4) Set to appropriate current range, 5) Turn power back on. Always start with the highest current range to avoid damaging the meter.

Use continuity test to: 1) Check if a fuse is blown (no continuity = blown fuse), 2) Test if wires are intact, 3) Verify switches are working properly, 4) Check for short circuits, 5) Trace circuits on a PCB. The continuity function typically beeps when resistance is below a certain threshold (usually 10-50Ω), indicating a complete path for current.

The diode test function measures the forward voltage drop across a diode. A good silicon diode typically shows 0.5-0.8V when forward biased (red probe on anode, black on cathode). When reversed, it should show "OL" (open circuit). Germanium diodes show about 0.3V, and LEDs show 1.5-3.5V depending on color. This test helps identify if a diode is functioning properly.