30
COMPONENT DESCRIPTION
START-UP
Line Pressure
Dry Side
Wet Side
LEGEND
FIGURE 3-3.
108MM 15-50hP VFD MPC CONTROL SYSTEM (START-UP) R00
When the compressor is started, a 10-second load delay is activated to ensure the compressor is up to
proper speed and minimum design pressure has been achieved. At this time the system is in a blowdown
condition, during which control air is supplied back to the inlet valve to keep it in a closed position and a
controlled amount of air is vented out of the sump tank. A predetermined blowdown orifice and an inlet
bypass orifice will maintain the unload sump pressure, nominal 30–40 psig (2.1–2.8 bar).
. At this time, the motor speed is at the minimum set point (VFD only).
Summary of Contents for UD Series
Page 6: ...vi About This Manual ...
Page 12: ...4 Introduction ...
Page 42: ...34 Component Description ...
Page 52: ...44 Operation ...
Page 66: ...58 Troubleshooting ...
Page 74: ...66 Parts Catalog 8 5 COMPRESSOR FRAME AND DRIVE ASSEMBLY Figure 8 1 AS801 25UD 50UD VFD R00 ...
Page 76: ...68 Parts Catalog 8 6 CONTROL ASSEMBLY OPEN Figure 8 2 1072190415 609 R00 ...
Page 78: ...70 Parts Catalog 8 7 STARTER ASSEMBLY ENCLOSED Figure 8 3 AS802 405060 PANEL R03 ...
Page 94: ...86 Parts Catalog 8 15 COOLING ASSEMBLY AIR COOLED Figure 8 11 AS804 50UDAC INLINE R00 ...
Page 100: ...NOTES ...
Page 101: ...NOTES ...