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4.1.3 Electrode Holder Assembly
To remove the electrode holder assembly from the analyzer, first unplug the
sample intake tubing on the right side of the module, then the sample sensor
cable, then remove the reference solution tubing connector and last, take out the
waste tube (green tag) at the left side of the electrode holder. The electrode
holder can now be removed by pressing the two plastic tabs (right and left side
of the module) and sliding the module forward. Press the plastic tabs again to
release the second detent and completely remove the module from the analyzer.
The sample sensor and/or the left side electrode holder can be removed and
replaced by removing the screws on the under side of this module. The Illus-
trated Parts List in Section 8 provides a detailed reference of the parts of this
assembly.
4.1.4 Peristaltic Pump Assembly
Replacement of the roller assembly of the peristaltic pump can be accomplished
by removing the pump tubing and firmly pulling the roller assembly toward the
front. To replace the roller assembly, align the roller and the flat on the motor
shaft and press the replacement roller into position.
To remove the motor, first remove the rear panel assembly and SBC Board as
described in Sections 4.1.7 and 4.1.8. Now, the electrical connector on the
lamp board can be accessed to unplug the motor connector. The motor can
now be removed by removing four screws located on the front of the housing
near the peristaltic pump.
4.1.5 Solenoid Assembly
Removal of each solenoid is identical. Each solenoid valve has a removable
pressure piece which is held in place by a solenoid cap. To remove the pres-
sure piece, locate the arrow on the solenoid cap and remove the solenoid cap
by sliding it off the solenoid shaft in the direction of the arrow. This exposes the
pressure piece which can now be removed from the solenoid shaft. To replace
pressure piece and cap, energize the solenoid as described in Section 3.2 (Test
Valves). This extends the solenoid shaft to the outermost position for ease in
replacing pressure piece and cap. Removal of the pressure piece and cap is
required prior to removing the solenoid and allows for easier replacement of the
tubing under each solenoid.