1 Safety
The MRU-30 meter has been designed to carry out measurements which results determine the
safety conditions of the installation. Therefore, in order to provide conditions for correct operation and
the correctness of the obtained results, the following recommendations must be observed:
Before you proceed to operate the meter, acquaint yourself thoroughly with the present manual
and observe the safety regulations and specifications determined by the producer.
The MRU-30 meter has been designed for the purpose of measurements of earth connection and
equipotential bonding, and also ground resistivity, Any application that differs from those specified
in the present manual may result in a damage to the device and constitute a source of danger for
the user.
The device must be operated solely by appropriately qualified personnel with relevant certificates
to carry out measurements of electric installation. Operation of the meter realized by unauthor-
ized personnel may result in damage to the device and constitute a source of danger for the user.
Using this manual does not exclude the need to comply with occupational health and safety regu-
lations and with other relevant fire regulations required during the performance of a particular type
of work. Before starting the work with the device in special environments, e.g. potentially fire-
risk/explosive environment, it is necessary to consult it with the person responsible for health and
safety.
It is unacceptable to operate the following:
A damaged meter which is completely or partially out of order,
A meter with damaged test leads insulation,
A meter stored for an excessive period of time in disadvantageous conditions (e.g. excessive
humidity). If the meter has been transferred from a cool to a warm environment of a
high level of relative humidity, do not start doing measurements until the meter has
been warmed up to the ambient temperature (approximately 30 minutes).
Before measurements may commence, make sure the test leads are connected to the appropri-
ate measurement sockets.
The meter can’t be powered from other sources than those mentioned in this manual.
The meter’s inputs are electronically protected from power surge, as a result for example, of ac-
cidental connection to the power supply source:
- for all input combinations –up to 276 V for 30 seconds.
Manufacturer’s calibration doesn’t include the resistance of test leads. Displayed result is sum
of the measured object and the test leads resistance.
The device complies with the following standards: EN 61010-1 and EN 61557-1, -4, -5.
