Benning ST 755+ - Testing the Patient Leakage Current

Testing
9.5 Individual tests
5284 / 08/2023 en BENNING ST 755+ / ST 760+ 87
Procedure
1. Start the test.
2. Use the test probe to scan all accessible conductive components of the test sample.
3. If you are using the direct or differential current measuring method, change the polarity of
the mains voltage at the test socket [}page31].
4. Use the test probe again to scan all accessible conductive components of the test sample.
Test the test sample in all switch positions (test sample functions), if available.
In the case of automatic testing, the test is completed automatically. Only if the test time for
automatic testing is set to ‘infinite’(0), measurement must be completed manually.
Result
If the value measured with the alternative leakage current measuring method exceeds 1mA,
you must carry out the direct current measuring method.
9.5.6 Testing the patient leakage current
The patient leakage current test [}page45] is intended to check medical electrical devices of
protection classesIandII for proper insulation capacity at mains voltage. This is to ensure that
no leakage current flows from the active applied parts to earth and that there is no risk of a
dangerous electric flow for the patient.
Requirements
• Approved safety measuring lines
• Please observe the requirements for measuring [}page71].
• The test sample is disconnected from the mains.
• Make sure that you are familiar with the procedure for manual [}page77] and automatic
[}page76] testing.
• The test sample has passed the protective conductor resistance test [}page79].
• Make sure that you know the necessary measuring points.
• The test sample has passed the insulating resistance test [}page80].
• The measuring circuit of the setup must be closed.
• The test sample is connected according to the connection diagram.