Ingersoll-Rand EP 20-ESP, Руководство оператора/инструкция по эксплуатации и перечень запасных частей

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3.5 SETTING NEMA 1 PRESSURE SWITCH
1. Open isolation valve, allowing control system to
sense “line” pressure.
2. Start the compressor.
The compressor should load if the line pressure is
lower than then the maximum discharge pressure stat-
ed on the compressor data plate. It may be necessary
to vent air from customer system load unit.
3. Slowly close the isolation valve allowing the air line
pressure to rise to the maximum discharge pressure
or “trip” setting of the pressure switch.
4. Remove cover from pressure switch (See Figure
3.5-1). Adjust as required by turning range adjustment
screw clockwise to increase and counterclockwise to
decrease trip setting (See Figure 3.5-2). When 1PS
trips, the compressor will unload. When the line pres-
sure falls to the reset point of 1PS (about 12 psig/.8
bar), the unit should reload. The pressure switch dif-
ferential is adjustable and factory set at about 12 psig
(.8 bar) to meet the requirements of the average appli-
cation.
Limited receiver and line storage may require a wider
differential. Sufficient receiver and line storage can
accept a narrow differential. If adjustment is required,
turn differential adjustment screw clockwise to
decrease the differential and counter-clockwise to
increase the differential.
5. Vent air from customer system to confirm switch
operation is satisfactory.
6. Replace switch cover and place unit in service.
CAUTION
When adjusting differential, adjust switch so that
maximum discharge pressure does not exceed
maximum discharge pressure stated on the
compressor data plate.
FIGURE 3.5-1 LOCATION OF PRESSURE SWITCH
FIGURE 3.5-2 NEMA 1 PRESSURE SWITCH (1PS)
PRESSURE SWITCH
RANGE
ADJUSTMENT
SCREW
DIFFERENTIAL
ADJUSTMENT
SCREW