07/ 2016
BENNING MM 12
32
9. Maintenance
Before opening the BENNING MM 12, ensure that it is not connected to a
source of voltage! Electrical danger!
Any work required on the BENNING MM 12 when it is under voltage
must be done only by a
qualified electrician. Special steps must be taken to prevent accidents
.
Before opening the BENNING MM 12, remove it from all sources of voltage as follows
-
First remove the both safety measuring leads from the measurement points.
-
Remove both safety measuring leads from the BENNING MM 12.
-
Turn the rotating switch
J
to ”OFF”.
9.1 Securing the unit
Under certain circumstances, the safety of the BENNING MM 12 can no longer be guaranteed.
This may be the case if:
-
there are visible signs of damage on the unit,
-
errors occur in measurements,
-
the unit has been stored for a long period of time under the wrong conditions, and
-
if the unit has been subjected to rough handling during transport.
In these cases, the BENNING MM 12 must be switched off immediately, removed from the
measuring points and secured to prevent it from being used again.
9.2 Cleaning
Clean the outside of the unit with a clean dry cloth. (Exception: any type of special cleaning cloth).
Never use solvents or abrasives to clean the testing unit. Ensure that the battery compartment
and the battery contacts have not been contaminated by electrolyte leakage.
If any electrolyte or white deposits are seen near to the battery or in the battery compartment,
remove them with a dry cloth, too.
9.3 Battery replacement
Before opening the BENNING MM 12, ensure that it is not connected to a
source of voltage! Electrical danger!
The BENNING MM 12 is powered by four 1.5 V mignon batteries (IEC LR6/ type AA). Battery
replacement (see figure 12) is required as soon as all segments of the battery symbol
4
have
disappeared and the battery symbol is flashing.
Proceed as follows to replace the batteries:
-
First remove the safety measuring leads from the measurement circuit.
-
Remove the safety measuring leads from the BENNING MM 12.
-
Turn the rotating switch
J
to “OFF”.
-
Remove the protective rubber holster
O
from the BENNING MM 12.
-
Put the BENNING MM 12 face down and unscrew the lower screw of the battery compart-
ment cover.
-
Lift the battery compartment cover off the bottom part.
-
Remove the discharged batteries from the battery compartment.
- Insert the new batteries into the battery compartment at the provided places (please
observe correct polarity of the batteries).
-
Lock the battery compartment cover into place on the bottom part and tighten the screw.
-
Place the BENNING MM 12 into the rubber protection frame
O
.
See figure 12:
Battery replacement
Remember the environment! Do not dispose of used batteries with domestic
waste. Dispose of them at a battery-collection point or as toxic waste. Your
local authority will give you the information you need.
9.4 Fuse replacement
Before opening the BENNING MM 12, ensure that it is not connected to a
source of voltage! Electrical danger!
The BENNING MM 12 is protected against overload by means of an integrated fuse (G melt
insert) 440 mA fast-acting and an integrated fuse (G melt insert) 11 A fast-acting (see figure 14).
Proceed as follows to replace the fuses:
-
First remove the safety measuring leads from the measurement circuit.
-
Remove the safety measuring leads from the BENNING MM 12.
-
Turn the rotating switch
J
to “OFF”.
-
Remove the protective rubber holster
O
from the BENNING MM 12.
-
Put the BENNING MM 12 face down and unscrew the lower screw of the battery compart-
ment cover.
-
Lift the battery compartment cover off the bottom part.
-
Lift one end of the defective fuse from the fuse holder.
-
Push the defective fuse out of the fuse holder completely.
-
Replace the defective fuse with another of the same rated power, same triggering charac-
teristics and same dimensions.
