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CMC TECHNICAL REFERENCE MANUAL
1X36003 Version 2.52
1996-1999 Ingersoll-Rand Company
Date of Issue: 18-Oct-1999
too slow a speed for an extended period. This is ACCELERATE-2. The turbine must
reach the Minimum Slow Roll Speed (approximately 25% of Full Speed) to continue.
12. Once the turbine gets past the Minimum Slow Roll Speed and is less than the Maximum
Slow Roll Speed (approximately 50% of Full Speed), the turbine is in the slow rolling
zone and the compressor is SLOW ROLLING. The User may leave the compressor in
this mode indefinitely. The CMC monitors the compressor speed (through the speed
analog input) in this mode. The Idle/Rated Driver Speed switch is turned to the Rated
position.
13. When the turbine speed exceeds Maximum Slow Roll Speed, the Starting Timer begins
(60 seconds maximum) and is STARTING. This is the same time for motor driven
compressors; therefore, the User must put enough steam to the turbine to get the speed
above the low trip speed before the timer expires. At this point, the compressor has
started and runs as described elsewhere.
Instrumentation for Turbine Driven Compressors
Centac Microcontroller
Turbine
Compressor
Electronic
Governor
Discrete Outputs (DO)
Discrete Inputs (DI)
TTV Solenoid Energize (Driver Permissive)
CR1
Analog Input (AI)
TTV Limit Switch
Driver Speed
Rated/Idle
Switch
on Panel
Door
Common Trip
Start - Momentary
Stop - Momentary
Reset - Momentary
Speed
DI
AO
AI
Solenoid Steam Valve
Trip Valve
TTV Solenoid
Manual Latch
Limit Switch
Steam
Throttle Valve
DO
Speed
Driver Speed Rated/Idle