FE ZAJ, Service Manual

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6
TN512955-E
4-1. Replacement of restrictor
Stop the analyzer as described in section 2.1, “How to stop analyzer”. Then, pull out the inner case.
The restrictor for reference gas line should be replaced when it is clogged (if gas flow is reduced to
less than 5 mL.) Be careful when handling the restrictor to prevent it from being clogging with
foreign matter since the restrictor diameter is very small.
Never touch the restrictor directly. If the restrictor is dropped or touched in error, rinse it with
acetone for about 10 seconds and mount it after drying.
After restrictor replacement, apply soapy water to the connections of the pipe and joint and check for
a gas leak. After confirming that there is no sign of a gas leak, check the gas flow to the restrictor
(5 to 20 mL).
Photo 4-1 Replacement of restrictor Illustration of disassembly
4-2. Replacement of switching power supply
The switching power supply is classified into two types for magnet driving and for circuit use.
As shown in the Photo 2-3, SW power supply (1) is used for magnet driving and SW power supply
(2) for circuit use. To replace the switching power supply, perform “how to stop analyzer” given in
section 2-1. Turn OFF this instrument power switch and disconnect the AC power cable. Then,
pull the inner case out of the instrument as described in section 2-3, and remove the mounting board
on which the switching power supply is mounted by loosening 2 screws from the top. Disconnect
the primary and secondary connectors. Remove 4 screws and insulation washers fastening the
mounting board and switching power supply to remove the switching power supply from the
mounting board. When mounting a new switching power supply, reverse the removal procedure.
Be sure to attach insulation screw washers required for mounting the new switching power supply on
the mounting board. For replacement of switching power supply (1), check the magnet driving
pulse (section 5-2), and for switching power supply (2), check voltage for the printed circuit board as
shown in section 5-1.
4. REPLACEMENT OF PARTS
Pipe
Cap screw
Filter
Packing
Restrictor
Packing
Joint
Do not turn this wrench.
Turn with wrench.
ZAJ ZAJ