Operation Manual

8
Line impedance
- The low limit prospective short-circuit current value depends on fuse type, fuse current rating,
fuse trip-out time and I
PSC
-scaling factor.
- Thespeciedaccuracyoftestedparametersisvalidonlyifthemainsvoltageisstableduring
the measurement.
Resistance to earth (BENNING IT 120 B only)
- If the voltage between the test terminals H and E is higher than 30 V the earth measurement
will not be performed.
- If a noise voltage higher than approx. 5 V is present between the H and E or S test terminals, a
warning symbol “ ”willbedisplayedinthemessageeld.Themeasurementresultsmaybe
affected!
TRUE RMS current (BENNING IT 120 B only)
- Only current clamps with a transformation ratio of 1000:1 should be connected. We recom-
mend to use the current clamp adapter BENNING CC 2 which can take measurements from
0.5 A - 20 A.
- An additional error of the connected current clamp has to be included into the measuring error!
Luminous intensity (BENNING IT 120 B only)
- Shadow and irregular incidence affect the measurement result!
- Pleaseobservethatarticiallightsourcesreachtheirfullcapacityafteracertaintimeonly.
For this reason, they should be switched on for the respective time before carrying out
measurements.
Testing the PE connection
- The PE terminal can only be tested when the function selector switch is set as follows: Z
l/Ik
(LN/L); Z
s/Ik
(L/ PE); FI/ RCD TEST.
- For correct testing of the PE terminal, the TEST key has to be touched for a few seconds.
- Makesuretostandonanon-isolatedoorwhilecarryingoutthetest,otherwisethetestresult
may be wrong.
2.2 Batteries
-  When battery cells have to be replaced or before opening the battery/fuse compart-
ment cover, disconnect any measuring accessory connected to the BENNING IT 110/
BENNING IT 120 B and power off the instrument. Hazardous voltage inside!
- Insert cells correctly, otherwise the BENNING IT 110/ BENNING IT 120 B will not operate and
the batteries could be discharged.
- If the BENNING IT 110/ BENNING IT 120 B is not used for a long period of time remove the
batteries from their compartment.
- Alkaline or rechargeable Ni-Cd or Ni-MH battery cells (size AA) can be used. The operating
hours are given for cells with a nominal capacity of 2100 mAh.
- Do not recharge alkaline battery cells, danger of explosion!