4-10 Solar 8000M/i patient monitor 2026265-075C
Maintenance and checkout: Electrical safety tests
Ground continuity test
1. Disconnect the device under test from the power outlet.
2. Connect the negative (–) lead of the DMM to the protective earth
terminal (ground pin in power inlet connector) or the protective earth
pin in the mains plug (ground pin in power cord).
3. Set the DMM to the milliohm (mΩ) range.
4. Connect the positive (+) lead of the DMM to all exposed metal
surfaces on the device under test.
5. Resistance must read:
0.1 ohm or less without power cord
0.2 ohms or less with power cord
Impedance of protective earth connection
This test stresses the ground system by using special ground bond
testers and is normally only required as a manufacturing production test
to receive safety agency compliance.
Some country agencies do require this test after field equipment repairs
(i.e. Germany's DIN VDE 0751 standards). Consult your country/local
safety agency if in question.
Check compliance as follows:
1. A current of 25A from a current source with a frequency of 50 or 60
Hz with a no-load voltage not exceeding 6 V is passed for at least 5
seconds through the protective earth terminal or the protective earth
pin in the mains plug and the equipotential stud which could become
live in case of failure in basic insulation.
2. The voltage drop between the parts described is measured and the
impedance determined from the current and voltage drop. It shall not
exceed the values indicated.
When taking this measurement, move the unit's power cord around.
There should be no fluctuations in resistance.
For equipment without a power supply cord the impedance
between the protective earth terminal and the ground tabs of the
Video In connector which is protectively earthed shall not exceed
0.1 ohms.
For equipment with a power supply cord the impedance between
the protective earth pin in the mains plug and the ground tabs of
the Video In connector which is protectively earthed shall not
exceed 0.2 ohms.
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