13-18-604 Page 28
Heat Exchanger Fan/Motor and Starter
- The combination axial fan/motor provides cooling air for the
heat exchangers and electronics box. The starter provides control for the fan motor only, as the latter
includes its own thermally-resettable, internal overload protection. This device is designed to operate
with 3 ph-60 Hz-460 vac electrical power – the necessary electrical wiring has been provided.
Main Motor Ventilation Fan/Motor and Starter
–The combination axial fan/motor cools the main motor
by blowing fresh air over its body. The starter provides control for the fan motor only, as the latter
includes its own thermally-resettable, internal overload protection. These devices are designed to
operate with 3 ph-60 Hz-460 Vac electrical power – the necessary electrical wiring has been provided.
Control Transformer
- This device reduces the incoming power voltage to 110-120 volts for use by
various control components (e.g., 24 vdc power supply, electrical enclosure cooling fans, etc.). Two
primary fuses and one secondary fuse are provided for overload protection.
Power Supply (24vdc)
- This device supplies electrical power to the AirSmart controller and various
solenoid valves.
For Letter References A thru U below, see Figure 4-2, page 29.
Inlet (Poppet) Valve (B)
– This device is located at the intake flange of the compressor. When the
compressor is running, a 3-way solenoid valve, energized by the AirSmart controller, vents the poppet
internals to atmosphere, allowing it to open (normal state). When the compressor is stopped, a sump
pressure signal is fed to the poppet internals, forcing it closed and preventing trapped air and oil within
the compressor from exiting through the inlet filter. See SECTION 10, page 63 for further details.
Minimum Discharge Pressure/Check Valve (G) –
This device maintains a minimum pressure (60psig)
within the air/oil reservoir, thus insuring (lubrication/cooling) oil injection flow into the compressors. It also
prevents the back flow of compressed air from the customer’s piping back into the compressor package
when the compressor is not running. See SECTION 9, page 61 for further details.
Oil Mixing Valve (L)
– This device prevents the compressor from operating at a pressure and
temperature combination that condenses water vapor in the oil system. The servo-driven, 3-way, ball
valve mixes cooled and hot oil, prior to delivery to the oil filter and oil injection line, as commanded by an
algorithm residing in the package controller. See SECTION 5, page 43 for further details.
Pressure Relief Valve (O)
– This device protects the pressure containing components of the compressor
package against high pressure exceeding 188.5 psig. See SECTION 11, page 65 for further details.
Inlet Feed Valve (C)
- This (three-way solenoid) device supplies/vents the required pneumatic signal to
actuate the inlet poppet valve. When energized, it opens (pressurizes) the inlet poppet valve and when
de-energized, it closes (vents) it.
Ball Valve – Oil Drain (N) -
This device allows the drainage of the oil charge held in the reservoir during
oil change operation.