Enofrigo MUSIC Serie Manual De Instrucciones página 83

d3: Defrost start delay
This parameter determines the time that must elapse, when the defrost is activated,
between the stopping of the compressor (electric heater defrost) or the starting of the
compressor (hot gas defrost), and the activation of the defrost relays
on the main and auxiliary evaporators. The delay 'd3' is useful, in the hot gas defrost,
to ensure a sufficient quantity of hot
gas for the defrost before the activation of the cycle reversing valve, in very special
applications (see paragraph "Description of software functions").
Default: d3=0 minutes.
d4: Defrost when the instrument is switched on
Activates a defrost when the instrument is switched on.
Warning: this request has priority over the activation of the compressor and the conti-
nuous cycle.
The possible values are:
d4=0, no defrost is performed when the instrument is switched on;
d4=1, a defrost is performed when the instrument is switched on.
Starting a defrost when the instrument is switched on may be useful in special situa-
tions.
Example: frequent power drops occur in the system, which cause the internal clock to
be reset. This clock calculates the interval between two defrosting operations, restar-
ting from zero. If the frequency of the power failure were, in an extreme case,
greater than the defrost frequency (e.g. a power failure every 8 hours, against a defrost
every 10 hours) the controller would never perform a defrost. In a situation of this type,
it is preferable to enable defrost on start-up, above all if the defrost is
controlled by temperature (probe on the evaporator), therefore avoiding unnecessary
defrosts or at least reducing the running times. In the case of systems with a large
number of units, if selecting defrosts at start-up, after a power failure all the units will
start defrosting, thus causing a voltage overload. To overcome this, the parameter d5
can be used. It adds a delay before the defrost, and this delay must obviously be diffe-
rent for each unit.
Default: 'd4'=0 the instrument does not perform a defrost on start-up.
dd: Dripping time
This parameter is used to stop (in minutes) the compressor and the evaporator fans
after a defrost to facilitate evaporator dripping,
If 'dd'=0 => there is no dripping time, therefore, at the end of the defrost the control
functions start immediately .
Note: if control with 2 compressor steps is selected (with or without rotation, H1= 12 or
13) the dripping acts on both steps.
English - 35
Code CT55900010 Rev. 03 - 07/'06