Manual

Gossen Metrawatt GmbH 65
11 Maintenance and Calibration
11.1 Displays – Error Messages
11.2 Fuses
Two measuring range inputs in the instrument are equipped with
one fuse each:
F1 = current measuring function
F2 = Rlo measuring function
(METRAHIT IM XTRA BT and METRAHIT IM E-DRIVE BT
only)
Maximum permissible voltage (= nominal voltage of the fuse) is
1000 V AC/DC each, and minimum breaking capacity is 30 kA
each.
Both fuses are tested automatically:
• When the instrument is switched on with the rotary switch in
the A position
• When the instrument is already on and the rotary switch is turned to
the A position
• In the active current measuring range when voltage is applied
If a fuse is blown or if no fuse has been inserted
the “FUSE” symbol appears at the display. The
respective fuse interrupts the associated mea-
suring ranges. All other measuring ranges
remain functional.
Replacing the Fuse
Attention!
!
If a fuse should blow, eliminate the cause of overload be-
fore placing the instrument back into service!
Attention!
!
Disconnect the instrument from the measuring circuit be-
fore opening the fuse cover in order to replace the fuse!
➭ Switch the instrument
off.
➭ Remove the rubber hol-
ster if applicable.
➭ Set the instrument face
down onto the working
surface.
➭ Loosen the screw in the
fuse compartment
cover (see figure at
right).
➭ Lift off the cover with
the screw and set it
aside.
➭ Pry the blown fuse out
using the flat side of the fuse cover.
➭ Insert a new fuse. Make sure that the fuse is centered, i.e. be-
tween the tabs at the sides.
Attention!
!
Use only the specified fuse type! The fuse must have a
breaking capacity of at least 30 kA (see page 63).
The use of repaired fuses or short-circuiting the fuse
holder is prohibited.
If fuses with other blowing characteristics, other current
ratings or other breaking capacities are used, the opera-
tor and the instrument are placed in danger.
➭ Replace the fuse compartment cover. In doing so, insert the
side with the guide hooks first.
➭ Retighten the screw for the fuse compartment cover.
➭ Replace the rubber holster.
➭ Dispose of the blown fuse with household trash.
11.3 Housing Maintenance
No special maintenance is required for the housing. Keep outside
surfaces clean. Use a slightly dampened cloth for cleaning. In par-
ticular for the protective rubber surfaces, we recommend a moist,
lint-free microfiber cloth. Avoid the use of cleansers, abrasives
and solvents.
11.4 Measurement Cables
Inspect the measurement cables for mechanical damage at regu-
lar intervals.
Attention!
!
Even in the case of minimal damage to the test leads, we
recommend sending them to GMC-I Service GmbH
without delay.
11.5 Recalibration
The measuring tasks performed with your instrument, and the
stressing it’s subjected to, influence aging of its components and
may result in deviation from the specified levels of accuracy.
In the case of strict measuring accuracy requirements, as well as
in the event of use at construction sites with frequent stress due
to transport and considerable temperature fluctuation, we recom-
mend a relatively short calibration interval of once per year. If your
instrument is used primarily in the laboratory and indoors without
considerable climatic or mechanical stressing, a calibration inter-
val of once every 2 to 3 years is sufficient as a rule.
During recalibration* at an accredited calibration laboratory
(DIN EN ISO/IEC 17025), deviations from traceable standards
demonstrated by your measuring instrument are documented.
Ascertained deviations are used to correct display values during
later use of the instrument.
We would be happy to perform DAkkS or factory calibration for
you at our calibration laboratory. Further information is available
on our website:
www.gossenmetrawatt.com ( COMPANY  Quality, Certifi-
cates and Declarations  DAkkS Calibration Center  Calibra-
tion Questions and Answers).
Recalibration of your instrument at regular intervals is essential for
the fulfillment of requirements according to quality management
systems per DIN EN ISO 9001.
Note
The test instrument should be calibrated at regular inter-
vals in a calibration laboratory accredited in accordance
with DIN EN ISO/IEC 17025.
* Examination of the specification, as well as adjustment, are not included in calibration.
However, in the case of our own products, any required adjustment is performed and
adherence to the specification is confirmed.
Message Function Meaning
FUSE Current measurement Blown fuse
In all operating modes Battery voltage has fallen below 3.3 V
0L Measurement Indicates overflow
Z
2
7
0
A
F
1
F
2