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Digital Multimeter Simulator

Master hardware diagnostics for CompTIA A+ Core 1 (220-1101)
0 / 8 completed
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DMM-17 PRIME
CAT III 600V
OFF
- - - -
 
Select mode
VΩ+
COM
RESISTANCE VOLTAGE DC
CURRENT DC/AC VOLTAGE AC
10A
MAX
VΩmA
+
COM
⎾
CAT III 600V  |  MAX INPUT 1000V DC / 750V AC  |  SIMULATED DEVICE — EDUCATIONAL USE ONLY
Test Scenarios
SCENARIO 1 / 8
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1
Select mode: Use the rotary dial
2
Select range: Choose appropriate range
3
Click Connect Probes to measure

Expected Setup

    ✔
    All Scenarios Complete!
    You've successfully diagnosed all 8 hardware scenarios using a digital multimeter. This skill is tested on CompTIA A+ Core 1 Objective 3.1.
    Multimeter Quick Reference

    DC Voltage

    • PSU 12V rail: 11.4V – 12.6V
    • PSU 5V rail: 4.75V – 5.25V
    • PSU 3.3V rail: 3.135V – 3.465V
    • CMOS battery: 2.7V – 3.3V

    AC Voltage

    • North America: ~120V
    • Europe: ~230V
    • Frequency: 60Hz (NA)
    • Range: ±10% nominal

    Continuity

    • Good cable: < 5Ω
    • OL = Open circuit
    • Beep = conductive path
    • Test: 1 wire at a time

    Resistance

    • Start at highest range
    • Never test live circuits
    • RAM: 100kΩ – 2MΩ
    • OL = open/infinite