SCM Cuno 2 Aqua, Manual

Page: 38 / 138

EN
OEM Manual – CUBO
2
AQUA
Pag. 36-EN UMT/WG T BT Rev3.0 – 08/10/2021
12 Troubleshooting
Symptom/alarm Possible Cause Check
Probes alarm/ wrong
reading - wrong connection
- wrong configuration
- wrong range (for pressure probe)
- wrong type of probe
- wrong placement of probe
- broken probe
Check the connection and the
configuration of the probe:
- type of probe
- wirings
- probes range (min and max)
- compare the value read by the probe
with the value read by a manometer
Missing communication
between Hecu and PSD
(power+/Inverter)/
ALP01/
ALW24
-Power plus device offline.
-No
communication between
HECU controller and PSD (Inverter
for compressor BLDC)
- check the PSD power supply (it must
be powered)
- check the RS485 wiring between
HECU and PSD
- check the serial address set in the PSD
(dip switch configuration)
- check the PSD address set in the
HECU controller
LT compressor does not
start - Some blocking alarm is forcing off
the compressor
- Regulation status of the unit is
OFF
- Most of evaporators are
performing a defrost (only if
evaporators
controller are
connected to the CDU via RS485)
- Wrong configuration of PSD
(power+ driver)
- Check the active alarm and try to reset
the alarm (consulting the alarms table
suggestions)
- Switch ON the unit
- Check the Defrost setting on mask
FBB15 (only if evaporators controller
are connected to the CDU via RS485)
- Force the download settings from
Hecu Controller to PSD
Parallel compressor
does not start
- Some blocking alarm is forcing off
the compressor
-Regulation status of the unit is OFF
-The LT compressor is OFF
- Wrong configuration of PSD
(power+ driver)
- Check the active alarm and try to reset
the alarm (consulting the alarms table
suggestions)
- Switch ON the unit
- Check the configuration of DSS (Fib05)
- Force the download settings from
Hecu Controller to PSD
Missing communication
between
Hecu and
evaporators
(MPXPRO/ULTRACELLA)/
ALW37
- Wrong connection of serial line
- Wrong serial address setting - Check the RS485 wirings/connection
- Check the serial address set in the
evaporator controller
- Check the protocol and baudrate
(Modbus, 19200bps)
Low SH alarm or DSH
alarm (ALW10/ ALT15/
ALT15) - Liquid is coming back to the
compressor
- Wrong reading of SH probes
(temp. and pressure)
- Wrong reading of discharge temp
probe - Check the SH in the evaporator
- Check the right operation of
Expansion valve in the evaporator
- Check the position of the probe and
be sure they are reading properly
- (for MT Comp or Parallel comp) check
that liquid is not coming back from