Webasto Frigo Top 25-35-40 RT-DS Mode D'emploi page 18

Neutral Zone Operation
(Only with R404A gas)
The neutral zone function makes it possible to keep the "Set Point" temperature stable inside
the refrigeration cell, automatically activating the cooling or heating cycles. The control device
automatically selects the needed function, allowing you to transport materials that must avoid
excessive cooling in the case of cold climates. The function is enabled through the db parameter
db (n, y) (when db = y the function is on; when db = n the function is off).
The cooling function is achieved by activating the compressor when the temperature is above the
"Set Point". The compressor is automatically shut off when the "Set Point" has been reached.
The heating function is achieved by simultaneously activating both the compressor and the
superheated defrost device when the temperature drops below the "Set Point". The compressor
and the defrost device are automatically turned off when the "Set Point" is reached.
Activating the DEFROST cycle
This procedure is to be performed in case of a system performance problem. Such problems are
noted by the excessive accumulation of ice on the refrigeration unit (very damp goods, very low
operating temperature). Activate by pressing the "DEFROST"
2 seconds. The defrost led blinks when the defrost is running (see FIG. 3). The programmed de-
frost has a maximum duration of 5 minutes. When this time has elapsed, a drip time is set before
the refrigeration system automatically starts up again. If the defrost conditions do not exist (e.g.
temperature detected by the probe inside the refrigeration unit is higher than the defrost off set-
ting), the operation is not performed.
System shutdown
When the refrigeration system is not used for extended periods of time, totally deactivate the sys-
tem and control device by performing the shut-down procedure indicated below.
To shut down the refrigeration system, press the "ON-OFF"
The word "OFF" will appear on the display and the control device is deactivated.
Press the "ON-OFF" key once more to restore instrument function.
WARNING: Do not shut down the system while the defrost cycle is running
18
ENGLISH
key and keeping it pressed for
key.
Accessing the programming menus
The two "Programming" menus, with two levels of access, let you modify the Default settings of
many control device operating parameters (see table on the following page). This operation must
only be performed by qualified personnel because programming errors could compromise system
function (before accessing this Menu, carefully study the parameter functions in control unit user's
manual).
To access the first level "Programming" menu (operation needed to modify the values of some
parameters when a defrost device is installed see the table on the following page), press the
"SET" and "DOWN" keys simultaneously. The compressor and defrost lights will start
blinking on the display (see FIG. 3) and the enabled parameters are displayed followed by their
current settings. Use the keys to modify the settings.
To save the new values and move on to the next parameter press the key "SET"
To exit "Programming" press the
matically, wait at least 15 seconds without pressing any key at all.
See the control device user's manual for instructions on how to access the second level "Pro-
gramming" menu.
Saving the hours of compressor operation
There is a counter (in hours) that saves the compressor operation hour count. The resolution is 1
hour and the range goes from 0 to 50000 hours. Saving interval: 5 min.
To display the counter, press the "CLOCK"
hours, appears on the display.
The first value displayed indicates the thousands. Press "CLOCK"
displayed, preceded by a minus sign.
For example: if the value saved is 1511 hours of operation, the first time the button is pressed
"001" (thousands) will be displayed, the second time the reading "-511" (units) will appear.
Repeatedly pressing the "CLOCK" button toggles between the two values.
During display, only the clock led remains on (see FIG.3).
If no key is pressed for 3 sec, the instrument reverts back to normal display.
WARNING: The value saved cannot be reset by the user, only Dixell can reset it using
a special reset procedure.
.
keys simultaneously or to exit "Programming" auto-
, button and the compressor operation count, in
again and the units are