OHAUS MB120 Service Manual page 55

CHAPTER 3 – MAINTENANCE PROCEDURES
3.11.1.6 Testing the Thermal Overload.
1. Performing a continuity test on the Thermal Overload; with power to the unit off, use
an ohm meter to measure resistance between the devise's poles. Resistance should be
zero Ω. If so, the devise is in good working condition if not continue to step 2.
2. Press the devise's reset button. Then re-test.
3. If test fails, replace the components.
4. Reassemble the Heating Unit.
5. Perform a Temperature Calibration. (See Appendix A.2)
6. Conduct Performance Tests.
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