Carel easy, Руководство пользователя

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14
GB
easy/easy compact +030220791 - rel. 2.0 - 30.05.2007
“Direct” mode (cooling) “Reverse” mode (heating)
OFF
ON
set point
rd
1
2
OFF
ON
set point
rd
1
2
Fig. 4.a
Key:
compressor request;
probe 1
Important:
the operating mode can also be set by external
contact connected to the multifunction digital input (parameter
A4=9). In this case, the contact controls operation (direct/reverse) with
priority over parameter r3.
r4: night-time set point delta
Value that automatically increases the set point temperature during the
night-time operation time bands.
r4=0:
night-time set point= St
r4>0: night-time set point= St + r4
Important:
to enable night-time operation, not only does r4 need to be set >0, but
the digital input must also be enabled and confi gured (see parameter
A4=4 curtain switch/night-time operation) or a night-time time band
enables (see par. “4.10 Clock and time band parameters” page 21);
night-time operation does not necessarily mean at night, but rather
the time bands in which the value of the set point is modifi ed. This
usually corresponds to the period in which the refrigerated cabinet is
not used (shop closed) and when the curtain is down.
rd Control diff erential
Value that is added to (or subtracted from, in ‘reverse’ mode) the
temperature set point.
rd= low values:
more precise temperature control;
high compressor On/Off switching frequency in the event of minimum
temperature deviations (with the risk of causing damage).
rd= high values:
less precise temperature control;
low compressor On/Off switching frequency in the event of minimum
temperature deviations.
Important:
the compressor can also be safeguarded using the
parameters that limit the number of activations/hour and the
minimum off time (see par. “4.6 Compressor protection” page 15).
4.4 Duty Setting
Safety function that ensures the operation of the compressor even in the
event of a control probe fault. If alarm E0 occurs, duty setting ensures the
operation of the compressor until the fault is resolved. The compressor,
not being able to be activated according to temperature, works cyclically
with an ON time equal to the value assigned to parameter c4 (in minutes)
and a fi xed OFF time of 15 minutes, see Fig. 4.b.
1.
2.
1.
2.
•
•
•
•
ON
OFF
C4
compressor
C4
OFF= 15 min.
Fig. 4.b
c4: compressor on time with duty setting
c4= 0 in the event of an ambient probe fault, the
compressor will be always off
c4= 100
(c4=99
for easy compact) the compressor will remain always on; and the
15 minute off time is not considered.
0<c4<100
(0<c4<99
for easy compact) at the moment a probe error (E0) is detected, the
duty setting cycle starts from the current status
of the compressor (that is, the status of the
compressor is maintained) and the time already
elapsed is ignored.The compressor times set by
parameters C1, C2, C3 are always observed.
Duty setting and defrost
If the control probe error occurs when the controller is in defrost mode,
the function is not stopped but rather is completed as required; in
addition, the defrost can still be performed when called. During the
defrost, the duty setting timer is not stopped but rather keeps counting
the ON and OFF times.
Duty setting and continuous cycle
If the continuous cycle is operating, the controller instantly exits this status
and activates duty setting (also for safety reasons, given that during the
continuous cycle the low temperature alarm is disabled). To re-activate
continuous cycle operation, the ambient probe fault must be resolved.
If the probe error is no longer present, the unit returns to normal operation.
The compressor again takes on the logic of the control, respecting the
times C1, C2, C3.
4.5 Continuous cycle
The continuous cycle is used to maintain refrigeration continuously
active, regardless of the temperature inside the unit. The function is used
to rapidly lower the product temperature, even below the set point, for
example after fi lling the cabinets. In this phase, the temperature may fall
below the set point by the value set for parameter AH.
To activate or deactivate the continuous cycle from the keypad, press the
UP + DOWN buttons for more than 3 seconds, the display will show “cc”
and the
icon will fl ash (2 fl ashes, pause) ;
cc: continuous cycle duration
This represents the time in hours that the compressor operates
continuously for so as to lower the temperature, even below the set
point. If cc=0 the continuous cycle is not activated. The controller exits
the continuous cycle procedure after the time set for parameter “cc” has
expired, or when reaching the minimum temperature (see the minimum
temperature alarm, parameter AL).
c6: temperature alarm bypass after continuous cycle
This is the time in hours during which all the temperature alarms
are deactivated after a continuous cycle. If the temperature of the
refrigerated unit, after the continuous cycle, lowers due to inertia below
the minimum temperature threshold (set point-AL), the activation of
the low temperature alarm is delayed for the time c6. In any case, the
continuous cycle is deactivated at the temperature (set point-AL).