Cen Tech Digital Multimeter 98025 Manual

The Cen Tech 98025 is a compact, handheld digital multimeter designed for basic electrical measurements. It features a large LCD display, multiple measurement functions (DC/AC voltage, DC/AC current, resistance, continuity, diode test), overload protection, data hold, and auto power-off. Powered by a 9V battery (included). Below are key sections for safety, features, operation, measurement procedures, maintenance, and troubleshooting.

1. Features at a Glance 2. Safety Information 3. Parts Identification 4. Specifications 5. Display and Controls 6. Measurement Procedures 7. Battery Replacement 8. Care & Maintenance 9. Regulatory Information 10. Troubleshooting

Features at a Glance

Key components: Large 3½ digit LCD display, Function/Range selector knob, Input jacks (COM, VΩmA, 10ADC), Test leads, Protective holster.

Feature	Description
DC Voltage	0.1mV to 1000V in 5 ranges
AC Voltage	0.1V to 750V in 2 ranges
DC Current	0.1µA to 10A in 5 ranges
AC Current	0.1µA to 10A in 5 ranges
Resistance	0.1Ω to 2MΩ in 6 ranges
Continuity Buzzer	Audible indication below 70Ω
Diode Test	Forward voltage drop measurement
Data Hold	Freezes displayed reading
Auto Power Off	Conserves battery after 15 minutes idle
Overload Protection	Fused current inputs; high-voltage protection

Safety Information

Read all instructions before use. Use proper personal protective equipment.

Do not exceed rated voltage or current limits.
Do not use if meter or test leads are damaged.
Disconnect power and discharge capacitors before measuring resistance or continuity.
Use proper jack for measurement (10A for high current).
Do not operate with battery cover removed.

WARNING! Risk of electric shock. Do not measure voltages above 1000V DC or 750V AC. Use extreme caution when working with high voltage.

First-Time Setup

Unpack and inspect contents. Install battery before first use.

Install battery: Remove battery cover, insert 9V battery, replace cover.
Connect test leads: Black to COM jack, red to VΩmA jack for most measurements.
Turn function knob to desired measurement type.
Test continuity: Touch probe tips together; buzzer should sound.

CAUTION! Ensure meter is off when changing batteries. Use only recommended battery type.

Specifications

Display: 3½ digit LCD, 1999 count.
DC Voltage: 200mV/2V/20V/200V/1000V ±(0.5%+2 digits).
AC Voltage: 200V/750V ±(1.2%+10 digits).
DC Current: 200µA/2mA/20mA/200mA/10A ±(1.0%+2 digits).
AC Current: 200µA/2mA/20mA/200mA/10A ±(1.5%+5 digits).
Resistance: 200Ω/2kΩ/20kΩ/200kΩ/2MΩ ±(0.8%+2 digits).
Diode Test: Test current 1mA, open circuit voltage 2.8V.
Power Supply: 9V battery (6F22 or equivalent).
Operating Temp: 0°C to 40°C (32°F to 104°F).
Dimensions: 135 x 70 x 35 mm.

Controls and Settings

Function Knob: Selects measurement mode and range. Buttons: HOLD (data hold), POWER (on/off).

Display Symbols: "OL" (overload), battery low, AC/DC, units (V, A, Ω), HOLD indicator.

Input Jacks: COM (common/ground), VΩmA (voltage/resistance/mA current), 10ADC (10A current). Auto-ranging: Automatically selects proper range in voltage/resistance modes. Manual ranging: Turn knob to specific range position.

Measurement Procedures

Always start with highest range if unknown value. Ensure proper lead connections.

DC Voltage: Set to V⎓, connect red to positive, black to negative.
AC Voltage: Set to V~, connect leads to circuit.
DC Current: Set to A⎓, break circuit, connect meter in series.
Resistance: Set to Ω, ensure circuit is de-energized.
Continuity: Set to •))) symbol, test for low resistance.
Diode Test: Set to diode symbol, red to anode, black to cathode.

Tip: Use HOLD button to freeze readings in hard-to-see locations.

Battery Replacement

Replace battery when low battery symbol appears.

Turn meter off and disconnect test leads.
Remove battery cover screw and cover.
Remove old 9V battery.
Insert new 9V battery, observing polarity.
Replace cover and screw.

WARNING! Do not operate with battery cover removed. Dispose of old battery properly.

Care & Maintenance

Clean with dry cloth only. Store in protective case when not in use.

CAUTION! Do not use solvents or water. Keep away from moisture, extreme temperatures, and strong magnetic fields.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits. CE marked: Conforms to European safety standards. Copyright © 2025 Cen Tech; trademarks of Harbor Freight Tools. For support, visit www.harborfreight.com or contact 1-800-444-3353.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No display	Dead battery	Replace 9V battery.
Inaccurate readings	Low battery/leads	Replace battery; check test lead connections.
Display shows "OL"	Overrange	Select higher range; check if measuring open circuit.
Continuity buzzer not working	High resistance	Check if resistance >70Ω; test on known good circuit.
Meter turns off automatically	Auto power-off	Turn knob to OFF then back to measurement mode.

Fuse Replacement: For 10A range: Remove battery, replace 10A/250V fast-blow fuse (rated).

Service: 1-800-444-3353; www.harborfreight.com