VAC DRI-TRAIN HE-493, Техническое руководство, Страница: 47 / 61

l#IC ______________________
Vacuum/Atmospheres
0
Valves - solenoid and manual
0
Regeneration Timer
0
Leaks
0
Circulator/Blower
0
Replacement of charge in purifier
0
Pressure (in glove box)
5-2.1 Solenoid Valves
Proper operation of the solenoid valves is verified by testing for the
presence of a magnetic field around the body of the solenoid. This is
done by placing a small magnet near the red cap on the solenoid. When
the solenoid is energized, the magnet will be strongly attracted to the
center core and the 60-cycle "hum" in the coil will be felt in the
magnet. If the solenoid is deenergized, only a steady pull will occur.
Reference to Figure 5-1, the HE-493 Schematic Diagram, provides the
necessary information on how to test any given solenoid when so desired.
�o attempt will be made here to explain the basic procedures normal to
tracing the flow of electrical current in the HE-493. This schematic is
straightforward, and a basic knowledge of electrical troubleshooting is
credited to anyone authorized to attempt any kind of trouble analysis of
the HE-493 ORI-TRAIN. Table 5-1 herein provides a list of the valves
and those evident symptoms which might logically point to a failure of
the valve to energize.
In the event of a solenoid valve failure, check the electrical operation
first. If the valve is/has been energized, but the failure symptom
persists, it may become necessary to disconnect the valve from its
plumbing to determine whether or not it is mechanically defective.
If the solenoid is found to be defective, this component may be easily
replaced by disconnecting its leads from its terminal strip and removing
the red plastic retaining cap.
In the event that a new solenoid is to be installed, it may be necessary
5-4
HE-493-7/80