MJOLNER 600 A MICRO-OHMMETER WITH DUALGROUND SAFETY
Choose the MJÖLNER 600 with excessive power resources for demanding applications, superior measurement accuracy and when 300 Amp continuous is required.
- Fully automatic testing – micro-processor controlled
- Safe test – DualGround™ and remote control
- Remote control from mobile app
- True DC – ripple-free current
- Lightweight suitcase – withstands the impact of water, dust, or sand
- Built-in thermal printer
- PC interface connection
The MJÖLNER600 is a 200 A micro-ohmmeter with DualGround safety features. It has been designed to measure the resistance of circuit breaker contacts, bus-bar joints, contact elements in busbars, and other high-current links with safety, ease of use, and versatility in mind. Indeed, it's high current capability goes up to 600 A DC (a true DC ripple-free current), so you avoid will problems with incorrect test results due to low test current when testing high current devices such as circuit breakers. As such, this micro-ohmmeter can be used anywhere to measure a low resistance value with high accuracy.
The MJÖLNER600 also has the ability to make measurements according to the DualGround™ method. This means that the test object will be grounded on both sides throughout the test, giving you a safer, faster, and easier testing process. Additionally, its lightweight yet rugged case design makes the MJÖLNER600 an excellent choice when you need a portable solution in the field. When the case is closed, the product can withstand the impact of water, dust, or sand – it even floats!
The MJÖLNER600 also has the ability to make measurements according to the DualGround™ method. This means that the test object will be grounded on both sides throughout the test, giving you a safer, faster, and easier testing process. Additionally, its lightweight yet rugged case design makes the MJÖLNER600 an excellent choice when you need a portable solution in the field. When the case is closed, the product can withstand the impact of water, dust, or sand – it even floats!
FEATURES AND BENEFITS
2. Connection for mains voltage
3. Switch for mains voltage
4. TEMP. SENSOR
This interface is for the connection of a temperature probe for temperature compensation.
5. INTERFACE
For communication with PC and MJÖLNER Win.
6. DATALOGGER
Port to connect a USB stick for data logging. Results can be viewed with Excel.
7. REMOTE
Remote control connectorThe remote controls current value, start /stop of measurement, and print-out function.
8. Printer
9. Keys to control the menu functions
10. Start/Stop key with status LED
11. Adjustment keys to set the measuring current and all menu values
12. DC+ current output
13. Sensing terminals
14. DC- current output
15. Shunt output
16. Clamp sense input
MJÖLNER 600 test system is designed to serve a number of applications. The most common are contact resistance measurements of low-, medium- and high-voltage breakers and also at bus-bar joints, and other high-current links. The contact resistance measurements concerning breaker testing are particularly called for in the following standards: IEEE C37.09-1999 and IEC 62271-1 (2011). If the contact resistance is too high this will lead to power loss and temperature rise, which often leads to serious trouble. To avoid such problems, it is necessary to check the resistance at regular intervals. The following table demonstrates how important low resistance is at high currents:
| Current | Contact resistance | Power loss |
| 10 kA | 1 mΩ | 100 kW |
| 10 kA | 0.1 mΩ | 10 kW |
| 1 kA | 1 mΩ | 1 kW |
| 1 kA | 0.1 mΩ | 100 W |
At 10 kA a contact with the resistance 0.1 mΩ gives a power loss of 10 kW. This power loss in one single point will definitely confer a temperature rise, which may result in overheating and possibly premature failure.
APPLICATION EXAMPLES
Circuit Breaker testing
- Test of circuit breaker contacts
- Test of the connections to the breaker
Testing of Bus-bar
- Test of Bus-bar joints
- Test of connections
Transformer testing
- Winding resistance – not on all types of transformers.
- Internal/external connections
Everywhere you need to test
a low resistance/high current connection
- Switches
- Disconnecting devices
- Safety ground connections
- Welding points
- Fuses
- Cables