HPS Rotary Screw Compressor Units
070.700-IOM (MAR 21)
Page 27
Operation
Table 8: ICM alerts
Description
ICM
alarm
text
Comments
No valve type
Selected
A1
At start-up
A1
and
CA
displays
Controller fault
A2
Internal fault inside electronics
All input error
A3
Not active if
i01
= 2 or
i02
= 2
When
i03
= 1 and AI A > 22 mA
When
i03
= 2 and AI A > 22 mA
Or Al A < 2mA
When
i03
= 3 and AI A > 12 V
When
i03
= 4 and Al A > 12 V
or Al A < 1 V
LOW voltage of
fail-safe supply
A4
If 5 VDC < Fail-safe supply
< 18 VDC
Check Supply
to ICAD
A5
If supply voltage < 18 VDC
If an alarm has been detected, the ICAD display (see
) alternates between showing Actual alarm and
present Opening Degree.
If more than one alarm is active at the same time, the
alarm with the highest priority takes preference.
A1
has
the highest priority,
A5
the lowest.
Any active alarm activates the
Common Digital Alarm
output (Normally Open).
All alarms automatically reset themselves when they
physically disappear.
Old alarms (alarms that have been active, but have physi-
cally disappeared again) can be found in parameter
i11
.
Reset to factory setting:
1. Remove the power supply.
2. Activate down arrow and up arrow push buttons at the
same time.
3. Connect the power supply.
4. Release down arrow and up arrow push buttons.
5. When the display on ICAD (see
) is alternating
between showing:
CA
and
A1
the factory resetting is
complete.
VFD skip frequencies
Warning
Failure to enter skip frequencies could cause cata-
strophic compressor failure or severe compressor
damage and result in serious injury or death.
For identifying elevated energy on
VFD
packages and es
-
tablishing skip frequencies, perform the following steps:
1.
With the HPS running loaded at full speed, physically
check the entire package for elevated energy, includ
-
ing any corresponding extremities such as valves, liquid
injection piping, brackets, tubing, oil cooler, and oil
piping.
2. Decrease the VFD speed by 100 rpm increments and
physically check the entire package for elevated en
-
ergy at each stage until the minimum speed range is
reached.
3.
As you identify the high energy hot spots, check them
with a vibration meter and for any readings that meet
or exceed one in. a second, skip that frequency range
in the controls panel for the VFD, eliminating the ability
of the package to operate within that frequency range.
4.
It is necessary to set the skip for each identified range
to as narrow a frequency band as possible, only making
it wider until full range is accommodated.
Refer to
070.902-IB, Vibration Severity Guidelines
for ac-
ceptable package vibration readings.
Review skip frequen‑
cies in
Normal start-up procedure
1.
Confirm system conditions permit starting the
compres sor.
2. Press the
RUN
key.
3. Allow the compressor to start-up and stabilize. Press
the
AUTO
key immediately below the Vi ratio label
on the operating display screen. Press the
AUTO
key
im mediately below the SV POS label on the operat-
ing display. The compres sor is now operating in the
automa tic mode.
4.
Observe the compressor unit for mechanical tightness
of the external piping, bolts, and valves. Ensure that
the machine is clean from oil and refrigerant leaks.
If any of these occur, shut down the compressor and
correct the problem as necessary using good safety
precautions.
5.
Ensure manway bolts remain finger tight after the com
‑
pressor unit is in operation, because the manway bolts
loosen as a result of pressurization.
Warning
Overtightening components could result in a fire,
serious injury or property damage.
Do not apply the manway bolt torque specified for
an unpressurized unit while the unit is pressurized.
Applying this torque when the manway is pressurized
can overstress the manway gasket. Overstressing
the gasket can lead to gasket failure and/or a system
leak.
Trained technicians are required for servicing.
Restarting the compressor unit after control
power interruption (plant power failure)
1. Check the variable setpoints.
2. Follow the