ETS-Lindgren HI-3520 Microwave Monitor (Archived) - Manual (Page 17)

HI-3520 Manual Page 13
5.0 MAINTENANCE
5.1 General
The unit has been designed for rugged field use. Normal
maintenance for this unit consists only of battery
replacement and calibration.
5.2 Battery Replacement
The unit furnished with a DL2450B lithium cell. Normal
operating life is 1000 hours. With the alarm in its latched
mode, the battery life is about 80 hours. The shelf-life of
the battery is about ten years when stored in a cool
environment.
The unit has a built in battery monitoring circuit that
generates a single beep and flash at one minute intervals
under low battery conditions. To replace the battery,
proceed as follows:
1. Turn the unit off. THIS IS IMPORTANT.
2. Loosen the screw that secures the battery cover
and remove the cover.
3. To remove the battery, pry it up with a small
screwdriver to clear the lip of the battery holder
before sliding it out.
4. Insert the new battery, making sure to observe
the correct battery polarity as indicated on the
retaining clip (i.e., +toward the clip).
5. Turn the unit on. The instrument should now be
operational and the one minute beep and flash
warning indicators should cease.
Archived 4/2/10