IMP57
EN - 10
5.3.
PHASE TO PE (PROTECTION CONDUCTOR) IMPEDANCE MEASUREMENT
AND PHASE TO PE PROSPECTIVE SHORT CIRCUIT CURRENT
CALCULATION
WARNING
Never use the instrument in electrical plants with Nominal phase to phase
voltage higher than 415V or a Nominal phase to neutral voltage or phase to
ground voltage higher than 240V.
The Phase to PE impedance measurement entails the flowing of a current up
to 116A between the above said conductors. This can cause tripping of
magnetothermal switch having rated value lower than 116A and will cause the
RCD tripping. If necessary execute the measurement upstream the switch or
RCD.
If possible disconnect all the low impedance loads connected downstream the
point where the test is to be carried out as the impedance of the above said
loads results to be in parallel with the impedance under test.
Always make sure that the upper and lower metal plate of the alligator clips
make good contact with the conductors of the circuit under test.
Never disconnect the Alligator clips or Test leads during the Test.
P1 C1 C2 P2
1
2
3
N
PE
Fig. 5:Instrument connection for phase to ground impedance measurement
1. Connect the IMP57 RS232 to MASTER instrument through RS232 cable (see
paragraph 4.2).
2. Connect the alligator clip to the Electrical pant according to Fig. 5.
3. Insert the 4 safety connectors into corresponding instrument's inputs
according to
sequence P1, P2, C2, C1
(see Fig. 5).
4. Check if the STATUS LED is light in Green.
5. Switch ON the MASTER instrument, select the "Phase to PE Measurement mode" and
Start the Test (see chapter 6).
For further details, description about Test results and Save procedure see chapter 6.
