MD 9020 Electrical & Electronic DMM Maintenance
14
5 Maintenance
WARNING
To avoid electrical shock, disconnect the meter from any circuit, remove the test leads
from the input jacks and turn OFF the meter before opening the case. Do not operate
with open case.
Cleaning and Storage
Periodically wipe the case with a damp cloth and mild detergent; do not use abrasives
or solvents. If the meter is not to be used for periods of longer than 60 days, remove the
batteries and store them separately
Trouble Shooting
If the instrument fails to operate, check batteries and test leads etc., and replace as
necessary. Double check operating procedure as described in this user’s manual.
If the instrument voltage-resistance input terminal has subjected to high voltage
transient (caused by lightning or switching surge to the system) by accident or abnormal
conditions of operation, the series fusible resistors will be blown off (become high
impedance) like fuses to protect the user and the instrument. Most measuring functions
through this terminal will then be open circuit. The series fusible resistors and the spark
gaps should then be replaced by qualified technician. Refer to the
LIMITED
WARRANTY
section for obtaining warranty or repairing service.
Battery and Fuse replacement
Battery use:
Standard 1.5V AAA Size (NEDA 24A
or IEC LR03) battery X 2
Standard CE Version series fuses:
Fuse (FS1) for
AmA current input:
0.5A/250V, F fuse;
Fuse (FS2) for A current input:
15A/250V, F fuse
Protection-reinforced CE + UL
Version series fuses:
Fuse (FS1) for
AmA current input:
0.63A/500V, IR 200kA, F fuse;
Fuse (FS2) for A current input:
12.5A/500V, IR 20kA, F fuse
Battery replacement for models with
battery access door:
Loosen the 2 screws from the battery
access door of the case bottom. Lift the
battery access door and thus the
battery compartment up. Replace the
battery. Re-fasten the screws.
