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out of the center hole. The seals will be destroyed but be careful not to
damage the Source Rod Bearing (200136). When replacing the seals, they
must be pushed or lightly tapped in place with a wood or soft metal dowel
to prevent damage.
The bearing has recesses for soil to accumulate to prevent binding. Clean
the bearing with a solvent and lubricate with silicon grease. Lightly coat all of
the seals and wipers with the same grease before reassembling. Reassemble
in reverse order.
6.1.7 Base Module
There are high voltage capacitors on the circuit board, which may be
charged to 900 volts. The current available is low but injury may occur due
to the surprise of receiving a severe shock. Discharge them by firstly sliding
the circuit breaker at the top of the batteries pack to the off position and
secondly pressing and holding the push-button switch at the top of the
circuit board for about one second.
Remove the Top Cover as described in 6.1.5. Remove the seven socket
head cap screws (001008) and lock washers (001029) around the edge of
the module. Carefully lift the Base Module up out of the Gauge Base. The
detectors may be replaced if necessary and the parts reassembled.
6.2 Battery Replacement
The batteries in this Gauge will last a very long time if the Gauge is not
stored at a high temperature. The expected service life is 1400 hours.
Replacement will be required within one to two weeks after the “LO BAT”
symbol appears in the Display while in use.
Replacement batteries should be high quality alkaline AA size cells such as
those made by Mallory (DURACELL). Do not replace with manganese zinc
cells except in an emergency for a short period of time. They will not last as
long and leakage may cause damage to the inside of the Gauge. Remove
the screws and lift battery cover. Slip the batteries out of the holders.
Replace the cells with the same orientation showing in the battery holders.
6.3 Electronic Modules Adjustment / Replacement
In order to improve reliability and maintain ease of service, the 5001SD
electronics is divided into four modules, which may be individually replaced.
Two of them have adjustments, which may need to be set.
6.3.1 Processor Module (200762)
This front panel module contains two counting systems, a programmed
microprocessor and a display. Field service is impractical other than
replacement. It is easily removed by means of four thumbscrews located
in the corners. The cable is disconnected from the Base Plane Module by
releasing the latches at each end of the connector. Note that the cable,
when properly installed, has no twists in it, only a 180° turn.
