RG66000889-REV.00
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The alarms E2 and E4 (E3 and E5 with unit model no.5) in water chillers activate the corresponding antifreeze heater.
Faulty EEprom alarm
Type
Input
Alarm
Delay
Reset
Error
Faulty
EEprom
- - - automatic
EE
It indicates a problem in the storing of data in the non-volatile memory of the unit (EEprom); the regulation process continues
on the basis of the data stored in the RAM. In case of power failure in the unit, the configuration is lost. To overcome this
problem, enter through password the "F" level, then return to normal operation by pressing PRG, so as to force the storing of
all parameters of the RAM in the EEprom. Neither the buzzer nor the alarm relay will be activated.
Defrosting indications, defrosting errors, communication errors and compressors maintenance
Type
Reset
Signal
Circuit no. 1 defrosting automatic
d1
Circuit no. 2 defrosting
automatic d2
Circuit 1 defrosting error
automatic/manual r1
Circuit 2 defrosting error
automatic/manual r2
Error in communication with terminal
automatic cN
Compressor no. 1 maintenance
manual n1
Compressor no. 2 maintenance
manual n2
Defrosting circuit no.1 and no. 2
Any time a defrosting cycle occurs, the display will show 'd1' or 'd2'. In this case, since it indicates a operating status, neither
the buzzer nor the alarm relay will activate; the yellow LED will not increase its blinking frequency. The temperature value
will blink alternatively to the defrosting indication.
Defrosting error on circuit no.1 and no. 2
If a defrosting cycle ends for time-out, but instead an end has been selected for the defrosting cycle when the threshold is
reached or from an external contact, the unit will display 'r1' or 'r2'. This message can be cleared through the alarm reset
procedure or by carrying out a new defrosting cycle correctly. In this case neither the buzzer nor the alarm relay will activate;
the yellow LED on the board will go on blinking at normal frequency. The temperature value will blink alternatively to the
defrosting error indication.
Error in the communication with the terminal
In case of failed communication between the single-compressor board and the terminal (both a local terminal and a remote
one) the unit will display 'Cn'; check the cable and the correct connection between cable and female connectors on the
board. Neither the buzzer nor the alarm relay will activate. The yellow LED will blink at normal frequency. The display will
constantly show the message Cn.
Maintenance of 1st/2nd compressor
When the compressor exceeds a selected operating hours threshold (factory-set value = 0 hour, therefore the control is
disabled) a message prompting maintenance will appear on the display. Neither the buzzer nor the alarm relay will activate.
The yellow LED will blink at normal frequency as well as the temperature value on display alternatively to the maintenance
indication.
5.2 Unit indication sequences
The unit displays messages every 32 seconds. When "µchiller" is in stand-by and there is at least one active alarm
condition, all the LED indicators will remain active except the buzzer. When in stand-by, however, "µchiller" detects probe
and eeprom alarms only; alarms from digital inputs will not be managed.
