Operation Manual

08/ 2012 28 / 58
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BENNING ST 750 A
10.6 RInsu – Insulating Resistance
The insulating resistance is measured between the active parts and each accessible conductive
part including the protective conductor. Moreover, it is measured between the active parts of a
primary circuit and the active parts of the SELV / PELV circuit. It is also measured between the
mains supply unit and all patient connections as well as between patient connections and accessi-
ble conductive parts including the protective earth. In the start menu, select the corresponding VDE
regulation and then the protection class.
Inthe"Testacc.toVDE....(Class.)",selectionmenu,press<RInsu-1>, <RInsu-2> and/or <RInsu-3>.
Start measurement by pressing <Start>.
By means of the setup program, it is possible to set the testing voltage of the device to lower values
(50-500 V DC, beyond the standard), e.g. if test samples are provided with integrated overvoltage ar-
resters. The corresponding nominal and actual values of the testing voltage are shown on the display.
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In the current issue of the DIN VDE 0751-1 standard, the measurement of the insulating
resistance is required, if it is considered to be convenient. Insulation measurement must
not be carried out, if it is excluded in the accompanying documents according to the
manufacturer'sspecications.
Limiting valuesfor the insulating resistance are not speciedinthe DIN VDE 0751-1 standard
(issue 2008). Here, it is possible to refer to recommendations of the manufacturer or to previously
measured values.
The limiting values according to VDE 0701-0702 or to VDE 0751-1 are taken into consideration.
Finish or stop the measurement by pressing <Stop>, press <Pause>/<Next> for a measuring
pause and press <Reset> to delete the measured value.
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Attention! Pressing the <Pause> button will stop the measurement. During the pause,
the test socket will remain live!
Besidesthemeasuringresult (measured value), the overall result is displayed (e.g."Pass"bya
greeneldand"Fail"byaredeld).
Accessible conductive parts which are not connected with the protective conductor must be
scanned by means of the probe / probe tip (VDE 0701-0702; 0751-1).
10.7 IPE – Protective Conductor Current
The protective conductor current measurement, a leakage current measurement carried out by
means of the differential current measurement method "Diff", the direct measurement method
"Dir.",thealternativeleakagecurrentmeasurementmethod"Alt."andthedifferentialcurrentmea-
surementmethodwith current clamp "Clamp" (DIN VDE 0404-4), corresponds to thesumofall
currents running through the insulation of a device to the protective conductor. For the differen-
tialcurrentmeasurementmethodwithcurrentclamp"Clamp",themeasuredvaluesofthecurrent
clamphavetobeenteredunder"Input"!
In the start menu, select the corresponding VDE regulation and then the protection class. In the
"Testacc.toVDE....(Class.)"menu,selectionmenu,pressthe"IPE"button.Selectthedesired
measurementmethod("Diff.","Dir.","Alt."or"Clamp")andstartmeasurementbypressing<Start>.
The limiting values according to VDE 0701-0702 are taken into consideration.