The low injection water pressure switch (PS3)
Also energized simultaneously are the injection
closing after the timing relay (6TR) has timed
water solenoid valve (SV1) and two timing relays (4TR
closed.
and 6TR). The SV1 valve opens, permitting flow of
injection water. The 4TR begins a 2-minute
The undervoltage relay (UV) contacts opening.
timed-to-close (on-delay) time out. The 6TR begins a
The motor overload (OL) contacts opening.
12- to 15-second on-delay time out.
A fuse (1FU, 2FU, 3FU, or 4FU) failing.
The timing relay (6TR) contacts close in 12 to 15
seconds, making the oil pressure and the injection water
Turning of the selector switch (3SEL) to the OFF
pressure switches (PS4 and PS3) operative in the safety
position.
shutdown circuitry.
Pressing of the remote EMER STOP pushbutton,
The timing relay (4TR) contacts are timed to
provided the selector switch (2SEL) is in the
close in 2 minutes, making the high dew point
REMOTE position.
temperature switch (HDP) effective in the safety
NOTE: If an automatic safety shutdown occurs, the
shutdown circuitry.
remote SAFETY ALARM will be energized by the
The compressor is now running fully loaded
control relay (2CR). If a manual emergency shutdown
occurs, the remote EMER STOP lamp will be lit. When
under control of the receiver air-pressure switch (PS1)
the unit is shut down, both remote and local ENABLE
and with all control and shutdown circuits operative.
RUNNING and MOTOR RUNNING lamps will be
NOTE: The motor will not start when the selector
extinguished Both of these lamps will remain lit during
switch (3SEL) is turned ON unless the pressure switch
the 10-minute unloaded run as a result of high air
(PS1) is closed and the air discharge temperature switch
pressure. Should the compressor not reload and it stops
(TS) is open. This prevents the compressor from
after the 10-minute time out, the MOTOR RUNNING
starting when there is adequate receiver air pressure or
lamp will be extinguished, but the ENABLE
when an abnormal temperature condition exists.
RUNNING lamp will remain lit.
The compressor is stopped in the
Injection Water Level Control
AUTOMATIC-125 psig mode of operation by one of
the following actions:
The level of injection (fresh) water level in the
The high receiver pressure switch (PS1) opening,
separator-holding tank is controlled by the operation of
float switches (LS3 and LS4) and solenoid valves (SV5
which de-energizes the control relay (1CR) and
and SV6).
off-delay timing relay (1TR). The 1TR contacts
time open in 10 minutes; this allows the
If the injection water rises to the high-level switch
compressor to run for 10 minutes in an unloaded
setting, the switch (LS3) closes, energizing the on-delay
condition before automatically stopping.
timing relay (2TR). When the 2TR relay times closed
in 6 to 8 seconds, provided LS3 remains closed, the
The high air temperature switch (TS) closing.
solenoid valve (SV6) is energized to drain the tank
The high injection water level switch (LS1)
If the water level in the separator-holding tank drops
closing.
low enough to close the low-level switch (LS4), the
The low injection water level switch (LS2)
timing relay 3TR is energized. If the 3TR contacts are
allowed to time closed (6 to 8 seconds), provided LS4
closing.
remains closed, the solenoid valve (SV5) is energized
The high condensate sump water level switch
to add water from the freshwater supply to the injection
(LS6) closing.
water system.
The high dew point temperature switch (HDP) in
Condensate Drain Control
the dehydrator closing after the timing relay
(4TR) has timed closed.
The dehydrator condensate sump is drained by the
The low oil pressure switch (PS4) closing after
solenoid valve (SV7) under control of the normally
closed level switch (LS5). When the liquid level in the
the timing relay (6TR) has timed closed
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