How to Use Your iFixit Digital Multimeter

Congratulations on getting an iFixit digital multimeter! Please take a moment to read through this page to familiarize yourself with your new multimeter.

• When measuring voltage, don't exceed 500 volts DC or 600 volts AC. The multimeter is rated CAT III-600V. Measuring above these limits may damage the multimeter and pose risk to electric shock. For a scale reference, most USB-powered devices are lower than 25 volts DC, and North America outlets are 120 volts AC.
• When measuring current, don't exceed 10 Amps AC or DC. Measuring above 10A will blow the fuse and pose risk to electric shock.
• Power down the circuit you're measuring when you measure resistance, continuity, capacitance, or diode. The multimeter may not measure those values correctly in an energized circuit.
• Power down the circuit you're measuring while you set up the multimeter to measure current. Unlike the other measurement modes, the multimeter acts like a short-circuit when it's in current mode, where a substantial amount of power can flow through it. If the circuit is live and you unintentionally short something as you set up, you may damage your circuit or the multimeter.
• When you measure capacitors, discharge it before you measure its capacitance.
• Inspect the probes and multimeter for signs of damage before you use them.

Follow this guide to install two AAA batteries into your multimeter.

Follow this guide to learn how to measure continuity, voltage, and resistance.

Follow this guide to learn how to measure current, frequency, and capacitance. The guide also explains how to use some of the multimeter's special features (diode, Live Wire, etc.)

Hold the Hz button for two seconds to toggle the flashlight. The flashlight turns off automatically after 15 seconds.

The multimeter has a built-in NCV sensor in the top-left corner of the body. This lets you sense whether a wire is live with AC by holding the sensor near the wire. When the multimeter is set to the NCV function, it will:

• Beep and flash one green indicator LED if it detects ~48-100V
• Beep and flash two red indicator LEDs if it detects over 100V

The NCV function may not always detect live AC. Never rely solely on the NCV function to determine whether a wire is live!

For full instructions on how to use the NCV function, check out this guide.

The Live Wire Test function allows you to determine which slot in an outlet is live with AC by touching it with a single test lead. You can use this function to determine if the outlet's wired correctly or not.

Don't use this mode as a voltage detector, as it may not always detect live AC.

For full instructions on how to use the Live Wire Test function, check out this guide.

The Battery Test function tests the battery voltage with a simulated load (30 Ω for 1.5V, 300 Ω for 9V). Compared to a DC voltage measurement (which puts almost no load while measuring), the Battery Test will show a more accurate representation of a battery's health—especially if the battery's worn out.

The VFC mode filters out high frequencies when measuring AC voltage or frequency, allowing the multimeter to measure noisy AC signals more accurately. Toggle it on and off by holding the Select/VFC button for two seconds.

This mode was originally designed to help diagnose variable-frequency motor controllers—hence the VFC name. These controllers use variable, high-frequency pulse-width-modulation (PWM) signals to drive motors.

By default, the multimeter will automatically select the measurement range and sensitivity based on the input. You can override this:

• Press the Range button to switch over to manual ranging
• While it's in manual range, press the Range button to cycle the measurement range in decreasing magnitude
• To return to auto range, press and hold the Range button for two seconds

The multimeter will automatically enter lower power mode after ~15 minutes. You can temporarily disable this behavior:

• Turn the function knob to OFF
• Press and hold the Select/VFC button
• Turn the function knob to the desired measurement function and release the Select/VFC button

When you turn off the multimeter, it will switch back to auto-shutdown.

Follow this guide to replace the batteries.

The low current fuse is socketed and can be easily replaced. Be sure to replace a blown fuse with these specifications:

• 600mA/600V Fast-acting, 5x20 mm size

The high current fuse is soldered to the board. You'll need to desolder the blown fuse to replace it. To make your life easier, order replacement fuses with leads pre-attached. Be sure to replace the blown fuse with these specifications:

• 10A/600V Fast-acting, up to 32 mm length
  • The factory fuse is 6.3x32 mm

Don't install fuses with higher current or voltage specifications, or you may damage your multimeter during use. You can safely install fuses with lower current or voltage specifications—your multimeter just won't be able to operate at its full range.

Follow this guide to replace blown fuses.

• 4-digit 9999-count True RMS
• Up to 600V AC, 500V DC
• Voltage input impedance: ~10MΩ
• AC/DC current: up to 10A
• Capacitance: up to 99.99mF
• Frequency measurement: 10Hz-60Khz
• Safety level: IEC61010-1 CAT III-600V
• Batteries: 2x1.5V AAA
• Operating temperature: 0 ~ 40 °C (32 ~ 104 °F)
• Operating humidity: <70% relative humidity

The accuracy specifications are based on an operating temperature of 18-28 °C and a relative humidity of <70%.

DC Voltage

AC Voltage

The accuracy is valid for 45-1000Hz.

Resistance

DC Current

AC Current

The accuracy is valid for 45-1000Hz.

Capacitance

Frequency measurement