Operation Manual
3
5.3.5 Testing selective (time-delayed) RCDs ..................................................................30
5.3.6 Contact voltage ......................................................................................................30
5.3.7 Trip-out time ...........................................................................................................32
5.3.8 Trip-out current ......................................................................................................33
5.3.9 Autotest ..................................................................................................................34
5.4 Loop impedance and prospective short-circuit current (Zs/ Ik) ......................................37
5.4.1 Loop impedance (loop resistance, Zl) ....................................................................37
5.4.2 Loop impedance (Zsrcd) ........................................................................................39
5.5 Line impedance and prospective short-circuit current ...................................................40
5.6 Phase rotation (phase sequence) ..................................................................................41
5.7 Voltage and frequency ...................................................................................................42
5.8 Testing the PE terminal ..................................................................................................43
5.9 Resistance to earth (BENNING IT 120 B only) ..............................................................45
5.10 TRUE RMS current (BENNING IT 120 B only) ..............................................................46
5.11 Illumination (BENNING IT 120 B only) ...........................................................................47
6 Working with measurement results (BENNING IT 120 B) ........................................49
6.1 Saving measurement results ........................................................................................ 49
6.2 Recalling measurement results ..................................................................................... 50
6.3 Deleting measurement results ...................................................................................... 51
7 RS232 and USB communication (BENNING IT 120 B only) .....................................54
7.1 BENNING IT 120 B-PC software .................................................................................. 54
8 Maintenance .................................................................................................................56
8.1 Replacing fuses .............................................................................................................56
8.2 Cleaning .........................................................................................................................56
8.3 Periodic calibration .........................................................................................................56
8.4 Service ...........................................................................................................................56
9 Technicalspecications ..............................................................................................57
9.1 Insulation resistance ......................................................................................................57
9.2 Resistance / continuity testing .......................................................................................57
9.2.1 LowΩresistancemeasurement .............................................................................57
9.2.2 Continuity ...............................................................................................................57
9.3 RCD ...............................................................................................................................58
9.3.1 General data ..........................................................................................................58
9.3.2 Contact voltage ......................................................................................................58
9.3.3 Trip-out time ...........................................................................................................59
9.3.4 Trip-out current ......................................................................................................59
9.4 Loop impedance and prospective short-circuit current ..................................................60
9.5 Line impedance and prospective short-circuit current ...................................................61
9.6 Phase rotation (phase sequence) ..................................................................................61
9.7 Voltage and frequency ...................................................................................................61
9.8 Online voltage monitor ...................................................................................................61
9.9 Resistance to earth ....................................................................................................... 62
9.10 TRUE RMS current ........................................................................................................62
9.11 Illumination .....................................................................................................................62
9.11.1 Illumination (BENNING Luxmeter type B) ..............................................................62
9.12 General data ..................................................................................................................63