1. Introduction
The PEAKMETER MS5910 Digital RCD Loop Tester is a compact, durable, and user-friendly instrument designed for comprehensive electrical inspections. It integrates advanced technology to accurately measure Trip-Out Current, Trip-Out Time, Voltage, and Loop Resistance. This manual provides essential information for the safe and effective operation, maintenance, and troubleshooting of your MS5910 tester.
2. Safety Information
Please read all safety warnings and instructions carefully before using this device. Failure to follow these instructions may result in electric shock, fire, or serious injury.
- Always ensure the device is in good working condition before use.
- Do not operate the tester in wet conditions or in the presence of explosive gases or dust.
- Observe all local and national safety codes.
- The device is designed for usage at an elevation of 2,000m CAT III 600V and 3,000m CAT II 600V. Adhere to these safety ratings.
- Pay attention to overheating and low battery voltage alarms, which indicate potential safety concerns or the need for battery replacement.
- Only use the provided test leads and accessories.
3. Product Overview
The PEAKMETER MS5910 is a versatile tool for electricians and technicians, offering a range of features for reliable electrical system diagnostics.
Key Features:
- Comprehensive Measurements: Accurately measures Trip-Out Current, Trip-Out Time, Voltage, and Loop Resistance (RL).
- Data Storage: Stores up to 100 groups of test results.
- PC Connectivity: USB 2.0 interface for data transfer to a computer.
- User-Friendly Design: Backlight indication for low-light conditions, Auto Power Off, and Auto/Manual Range selection.
- Safety Alarms: Overheating and low battery voltage alarms for enhanced safety.
Components:
The MS5910 package includes the main tester unit, test leads, alligator clips, a USB cable, a shoulder strap, and a carrying bag.



4. Setup
4.1 Powering the Device
The MS5910 is powered via an AC input. Connect the provided power cable to the AC IN port on the rear of the device (refer to Figure 3.3) and then to a suitable power outlet.
4.2 Connecting Test Leads
Connect the test leads to the appropriate input terminals on the MS5910. Ensure a secure connection. The alligator clips can be attached to the test leads for easier connection to circuits.

5. Operating Instructions
The MS5910 offers various measurement modes accessible via the rotary dial. Always ensure proper connection of test leads before initiating any test.
5.1 Selecting a Measurement Mode
Turn the central rotary dial (refer to Figure 3.2) to select the desired measurement function:
- LOOP L-N: For Loop Resistance measurement between Line and Neutral.
- U: For Voltage measurement.
- L-PE: For Loop Resistance measurement between Line and Protective Earth.
- RCD x1/2, x1, x5, AUTO RAMP: For Residual Current Device (RCD) testing at different current multipliers and an automatic ramp test.
- OFF: Powers off the device.
5.2 Performing Measurements
- Select the desired function using the rotary dial.
- Connect the test leads to the circuit or component to be tested according to the specific measurement type.
- Press the MEASURE button to initiate the test.
- The results will be displayed on the LCD screen.
5.3 RCD Testing
When performing RCD tests, select the appropriate current multiplier (x1/2, x1, x5) or AUTO RAMP mode. The tester will measure the trip-out current and trip-out time. Refer to the RCD tests current selection table in the Specifications section for expected values.
5.4 Display and Backlight
- Press the DISPLAY button to cycle through different display modes or information.
- Press the LIGHT button to activate the backlight for improved visibility in low-light conditions.
6. Data Storage and Transfer
6.1 Storing Test Results
The MS5910 can store up to 100 groups of test results. After a measurement is complete, press the MEMO button to save the current reading. Use the arrow buttons to navigate through memory locations if needed before saving.
6.2 Recalling Stored Data
To recall stored data, press the READ button. Use the arrow buttons to scroll through the saved test results.
6.3 Transferring Data to PC
The device features a USB 2.0 interface for transferring stored data to a personal computer. Connect the MS5910 to your PC using the provided USB cable (refer to Figure 3.3). Follow the instructions provided with the accompanying software (if applicable) to download and analyze the test results.
7. Maintenance
7.1 Cleaning
Wipe the device with a dry, soft cloth. Do not use abrasive cleaners or solvents. Ensure the device is powered off and disconnected from any power source before cleaning.
7.2 Storage
When not in use, store the MS5910 in its carrying bag in a cool, dry place, away from direct sunlight and extreme temperatures. If storing for extended periods, ensure the device is powered off.
7.3 Battery Replacement (if applicable)
The MS5910 features a low battery voltage alarm. If this alarm activates, ensure the device is connected to a stable AC power source. If the issue persists or if the device uses internal rechargeable batteries that are no longer holding a charge, contact customer support for service.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | No AC power, faulty power cable, device is OFF. | Check AC power connection. Ensure power cable is not damaged. Turn the rotary dial from OFF to a measurement mode. |
| Inaccurate readings. | Poor test lead connection, incorrect measurement mode, environmental interference. | Ensure test leads are securely connected. Verify the correct measurement mode is selected. Test in a stable environment. |
| Data transfer fails. | Faulty USB cable, incorrect software settings, driver issues. | Try a different USB cable. Ensure the correct software and drivers are installed on your PC. |
| Low battery alarm. | Insufficient power from AC source. | Ensure the device is connected to a stable and sufficient AC power supply. |
9. Specifications
The following table outlines the technical indicators and performance specifications for the PEAKMETER MS5910 RCD Loop Tester.

General Specifications:
- Model: MS5910
- Usage Elevation: 2,000m CAT III 600V, 3,000m CAT II 600V
- Data Storage: Up to 100 groups
- Interface: USB 2.0
- Features: Backlight, Auto Power Off, Auto/Manual Range
- Alarms: Overheating, Low Battery Voltage
- Dimensions: Approximately 13.78 x 10.63 x 4.33 inches
- Weight: Approximately 4.83 Pounds
10. Warranty and Support
For warranty information or technical support, please refer to the documentation provided with your purchase or contact the manufacturer directly. Keep your purchase receipt as proof of purchase.