User manual

ManualsBrandsdixell ManualsHousehold AppliancesIC200CX Series

1592022700 User manual iCHILL 200CX Rel. 1.0 22/04/2009

Pg.42/114

If the last compressor stops before the pump down pressure switch because of the CO33 time-out (maximum compressor on time after

turning off the P.D. solenoid valve), the ICHILL calculates the AL28 parameter (maximum number of pump down alarm per hour) and if

an alarm occurs the display will show the alarm code, the buzzer and the alarm relay will be on.

If the thermoregulation is stopped via digital input (as remote off) or from chiller/heat pump keys, during the pump down process the

chiller or the heat pump led will blink.

When the next thermoregulation restarts the PD solenoid valve turns on and after 1 seconds, if the pressure probe is higher then CO31,

the compressors start.

If the compressors do not restart within the CO33 time the pump-down alarm will signalled and the compressor are stopped. In this case

if AL30 =0 the compressor can restart only if the pressure switch becomes active, or if AL30=1 and the number of alarms per hour

becomes =AL29 only after the manual reset.

PAR. CO30 = 3 START UNIT WITH PUMP DOWN in CHILLER MODE (No PUMP – DOWN at START-UP)

In Heat pump mode the Pump down process is inhibited and the solenoid valve works in parallel with the compressor.

PAR. CO30 = 4 UNIT START/STOP WITH PUMP DOWN in HEAT PUMP

In Heat pump mode the Pump down process is inhibited and the solenoid valve works in parallel with the compressor.

23.4 PUMP DOWN ALARM DURING COMPRESSORS START- UP

ACTIVATION

If within the CO33 delay time (Maximum pump down restart time) the compressor/s do not restart because of the low pressure, the

instrument will signal B1PL (pump down alarm at the start-up of the circuit 1) or the label B2PL (pump down alarm at the start-up of the

circuit 2). With active alarm the restart procedure is disabled. The alarms can be:

• with Automatic Reset that is not logged, the buzzer and alarm relay are not activated.

• with Manual Reset that is logged, the buzzer and alarm relay are activated.

The parameter AL29 determines the number of pump down alarm events to turn from automatic to manual reset

The Reset is always manual if AL29 = 0

The Reset is always automatic if AL29 = 16

The reset becomes manual after AL29 = 1 ..15 events and the configuration of Par. AL30.

Par. AL30 defines if the reset of the AL29 alarm events can be forced from manual to automatic. In this case the alarm events, after

reaching AL29, is automatically reset but it is logged while the buzzer and the alarm relay are on.

In this way, in case of particularly critical condition, the unit restarts working without the help of the maintenance personnel.

RESET

• The Automatic Reset is activated when the next compressor thermoregulation is requested, in this case the pressure condition of

the pump down must be satisfied.

• The Manual Reset needs to enter the function Menu under the AlrM label. After the reset the next thermoregulation restarts if the

pump down pressure is in normal condition.

ATTENTION

If the pump down function is enabled, during the unit start-up from digital input as pump down pressure switch and also from

analogue input as low pressure transducer, the compressor will restart only if both the inputs are satisfied.

23.5 PUMP DOWN ALARM DURING COMPRESSORS SWITCHING OFF

ACTIVATION

If within the time delay CO33 (maximum pump down duration in off) the low pressure switch or the pump down pressure switch is not

active or the pump down setpoint is not reached, the last compressor is switched off. In this case after this timeout the instrument

signals the B1PH or 2 alarms, in both cases when active the compressor is stopped.

The alarm can be:

• with Automatic Reset that is not logged, the buzzer and alarm relay are not activated.

• with Manual Reset that is logged, the buzzer and alarm relay are activated.

The Parameter AL28 determines the number of pump down alarm events to turn from automatic to manual reset

The Reset is always manual if AL28 = 0.

The Reset is always automatic if AL28 = 16.

The reset becomes manual after AL28 = 1 ..15.