10
HARS-LX Series
10
Maintenance
Chapter 5
MAINTENANCE
5.1 Maintainability and Reliability
It is possible to maintain Model HARS-LX indefi
-
nitely. It is reliable due to its closed design and sealed
switches and resistors. It is possible to adjust the unit,
if necessary, because it has adjustable decades for 1
Ω
decades and above and resistance wire for lower
decades which can be trimmed. The unit is resistant
to electromagnetic interference (EMI) because of its
metal enclosure.
5.2 Preventive Maintenance
Keep the unit in a clean environment. This will help
prevent possible contamination.
The Model HARS-LX is packaged in a closed case
and uses completely sealed switches. This limits the
entry of contaminants and dust to the inside of the
switches. If it is maintained in a clean or air-condi-
tioned environment, cleaning will seldom be required.
Should cleaning be needed:
1. Remove the 4 housing screws from the side
of the instrument, and remove the housing.
2. Remove any dust or debris using optical
grade dry compressed air or a clean brush.
3. Replace the housing and reattach the 4 hous-
ing screws.
The front panel should be periodically cleaned to
eliminate any leakage paths from near or around the
binding posts. To clean the front panel:
Wipe the front panel clean using alcohol and a
lint-free cloth.
5.3 Calibration
The Model HARS-LX may be employed as a stand-
alone instrument or as an integral component of a
system. If used as part of a system, it should be
calibrated as part of the overall system to provide an
optimum system calibration.
If the HARS-LX is employed as a stand alone device,
the following should be observed:
•
Calibration Interval
•
General Considerations
•
Required Equipment
•
Calibration Procedure
5.3.1 Calibration Interval
The recommended HARS-LX Series calibration
interval is twelve (12) months.
If the instrument is used to transfer resistance values
only, recalibration is not required, assuming that there
has been no drastic change in the deviations of any
individual resistors.