Operation Manual

6
2 Safety and operational considerations
2.1 Warnings and notes
In order to reach high level of operator’s safety while carrying out various tests and measurements
using the BENNING instrument, as well as to keep the test equipment undamaged, it is necessary
to consider the following general warnings:
- The symbol  at the BENNING IT 110/ BENNING IT 120 B means: “Read the Instruction ma-
nual with special care to safety operation”. The symbol requires an action!
- Ifthetestequipmentisusedinamannernotspeciedhere,theprotectionprovidedbythe
BENNING IT 110/ BENNING IT 120 B may be impaired.
- Read this user manual carefully, otherwise use of the BENNING IT 110/ BENNING IT 120 B
may be dangerous for the operator, for the instrument or for the equipment under test.
- Do not use the BENNING IT 110/ BENNING IT 120 B or accessories if any damage is noticed.
- If a fuse has blown, follow the instructions in the instruction manual to replace it.
- Consider all generally known precautions in order to avoid risk of electric shock while dealing
with hazardous voltages.
- Do not use the BENNING IT 110/ BENNING IT 120 B in supply systems with voltages higher
than 550 V.
- Service intervention or adjustment procedure is allowed to be carried out only by competent au-
thorised persons.
- Use only standard or optional test accessories supplied by your distributor.
- Consider that older and some of new optional test accessories compatible with this
BENNING IT 110/ BENNING IT 120 B meet only overvoltage category CAT III/ 300 V. It means
that maximal allowed voltage between test terminals and earth is 300 V.
- Disconnect any measuring accessory and power off the BENNING IT 110/ BENNING IT 120 B
before opening battery/fuse compartment cover, hazardous voltage inside.
 Warnings concerning measuring functions
Insulating resistance
- Carry out measurements of the insulating resistance at discharged objects only!
- Disconnect all loads and close all switches for measuring the insulating resistance between
conductors of the system.
- Do not touch the object during the measurement or before it is completely discharged! Danger
of electric shock!
- When an insulation resistance measurement has been performed on a capacitive object auto-
matic discharge may not be done immediately. Warning message and actual voltage is dis-
played during discharge, until voltage drops below 10 V.
- Do not connect the test cables to an external voltage higher than 600 V (AC or DC), because
this might damage the tester!
Resistance/ continuity test
- Carry out the low-impedance measurement/ continuity test at discharged objects only!
- Thetestresultmightbeinuencedbyparallelimpedancesortransientcurrents.
Testing the PE connection
- If phase voltage is detected at the PE connection to be tested, immediately interrupt all measu-
rements and make sure that the error is corrected before going on with other work at the object!