Gardner Denver PUREAIR EWC99C, Руководство по эксплуатации и обслуживанию

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Operate the compressor until the desired discharge pressure is achieved – in case the supply
of air exceeds the demand, bleed some of the discharge air to achieve the target system
pressure.
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Back-out the adjustment stem until the subtractive valve starts to bypass air – the adjacent
pressure gauge should register movement of less than 1 psig. Now the device is ready to
feed a proportional air signal to the inlet poppet valve as the system pressure builds beyond
the present level.
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Tighten the lockout to secure the position of the adjustment stem.
The subtractive valve can be disassembled and the diaphragm and ports cleaned.
Water Pressure Relief Valve (ss) – This device protects the water treatment filtration system against
75 psig overpressure in the line common with the compressor inlet.
Air Pressure Regulator (All Seal Purge) ( n) - This device regulates the pressure of the air buffer
signal fed to all seals. It should be set to 5 to 7 psig.
Water Pressure Regulator (Inlet Seal Purge) (w) - This device regulates the pressure of water buffer
signal fed to the inlet seals. It should be set to 2 to 3 psig.
Pressure Gauge (o) – This 0 to 15 psig device displays the output signal from the pressure regulators.
Shuttle Valve (l) - Also known as a double check valve, the shuttle valve is a device which will take two
(2) supply signals and allow the one with the highest pressure to pass through.
System Pressure Transducer (s) - This device measures the delivery air pressure supplied to the
customer. The AUTO SENTRY W controller uses this measurement for loading/unloading logic. It is
located in the starter enclosure.
Reservoir Pressure Transducer (t) - This device measures the discharge pressure from the water
cooler. The AUTO SENTRY W controller uses this measurement to prevent loaded starts and to monitor
coolant pressure. It is located in the starter enclosure.
Injection Pressure Transducer (u) - This device measures the recirculation water filter discharge
pressure, prior to injection into the compressor. The AUTO SENTRY W controller uses this
measurement, in conjunction with that from the reservoir pressure transducer, to monitor the pressure
losses across the recirculation water filter. The AUTO SENTRY W controller displays a service warning
at 30 psig differential and shuts the package down at 40 psig differential. It is located in the starter
enclosure.
Air Filter Vacuum Switch (ww) - This device senses the air pressure at the discharge side of the air
filter. The AUTO SENTRY W controller displays a service warning when a 25” H
2
0 pressure level triggers
the switch. It is located in the starter enclosure.
Discharge Thermistor (v) - This device measures the compressor discharge temperature. The AUTO
SENTRY W controller uses this measurement for display and shutdown logic purposes. It is located at
the compressor discharge port.
Water Level Switches (z) - This assembly (three level switches) senses water level in the reservoir.
The AUTO SENTRY W controller uses the individual signals to drain or fill the reservoir with water and to
shut the system down if an exceedingly high water level prevails.
Water Solenoid Valves (aa, rr, tt) - The fill (tt) and drain (aa) valves respond to the signal from the
water level switches to fill or drain, respectively, water from the main reservoir. The dump (rr) valve
responds to signals from the PLC to dump the water charge stored in the water treatment reservoir when
the compressor unit is not operating.