
CMC TECHNICAL REFERENCE MANUAL
1X36003 Version 2.52
1996-1999 Ingersoll-Rand Company
Date of Issue: 18-Oct-1999
13
Capacity - Mass Flow
Power at
Coupling
Amps
Discharge
Pressure
MinLoad User Setpoint
(reset returns control here)
MinLoad
Surge
Index
Increment
MinLoad Control Setpoint
MinLoad Control Setpoint #1
MinLoad Control Setpoint #1
MinLoad Control Setpoint #3
(currently active)
Surge Indexing
Since the setting of MinLoad Control Setpoint is sensitive to many variables in a
compressed gas system, there is potential for the setting to require adjustment throughout
the operation of the compressor. When MinLoad is set incorrectly, one of two things can
happen. When MinLoad is set too high, the compressor will consume excessive power at
MinLoad. When MinLoad is set too low, the compressor is allowed to go past the surge line
and surge occurs.
When Surge Indexing is
enabled, it corrects the
situation when MinLoad is
set too low by automatically
adjusting MinLoad to a
higher value upon a surge.
The indexed setting,
MinLoad Control Setpoint
will remain in effect until
MinLoad User Setpoint is
manually changed on the
Operator User Interface, or
the Reset button is held for
more than five seconds.
When MinLoad User
Setpoint is manually
changed, the MinLoad
Control Setpoint is
automatically changed to
match the new setting and when reset the MinLoad Control Setpoint is reset to the original
MinLoad.
Entering a non-zero number into the MinLoad Surge Index Increment variable enables surge
Indexing.