Indicator Elements; Test Mode / Start-Up; Unit Characteristics; Door Contact - Pfannenberg DTS Série Notice D'utilisation Et De Montage

10.2 Indicator elements

The cooling unit has an operational display in the form of a LED on the
external hood of the unit. If the light of this indicator remains on when
the supply voltage is applied it shows that the unit is in the normal
operating mode. If a fault occurs or if the unit is in the start-up or test
mode, this indicator lights up in various flashing sequences which make
it easier to diagnose fault in the unit (see Sections 10.4 and 13)

10.3 Test mode / start-up

The test mode is basically activated after renewed connection of
the supply voltage and is independent of the instantaneous ambient
conditions when the door contact is closed.
First of all the unit runs through a start-up mode lasting 30 seconds
which is followed by a test mode lasting 30 seconds.

10.4 Unit characteristics

Modus Time curve Characteristics
Start-up t = 0s - < 30s No function
mode t = 30s
t = 32s
Test mode t >34s – 64s
The start-up mode is always additionally activated when the door
limit switch is closed (see Sections 10.5)

10.5 Door contact

To avoid an increased production of condensate and for safety
reasons a door limit switch should be connected to the terminals
provided (see circuit diagram (housing cover) or supplement)
By the opening of the switch cabinet door and thus the opening of
the switch all of the motors of the cooling unit are immediately
switched off. After closing of the door the start-up mode (see Sections
10.4) is run through which ensures a restart-up of the cooling unit
with a time lag.

10.6 Centralised fault indication

The signalling of a fault in the cooling unit is effected by the breaking
of a potential-free contact (see Sections 13). In this way a cable
breakage in the fault signalling line is also signalled
10.7 Multimaster – bus
Comfort- or Multi-Controller)
In the multimaster configuration, cooling operation is initiated by
the cooling unit which reaches the operating threshold (T
first. All of the cooling units connected to the multi-master bus switch
to cooling operation. The cooling mode is terminated by the unit
which is the last to go below the operating threshold
(T - 2K).
setp.
10.8 Setting possibilities
By means of a DIP switch (Standard- and Comfort-Controller) or
from a display and control unit (Multi-Controller), various switch
cabinet temperatures as well as limit temperatures can be selected.
14
Internal fan start up
External fan and
compressor start up
Flashing sequence of the
status indicator:
"off-dark-light-dark-off".
Fault signal contact is closed.
Compressor and fans
remains in operation during
the period. Flashing sequence
of the status indicator:
"off-dark-light-dark-off".
Fault signal contact is open.
Should a fault arise during
the test mode, the unit goes
into the fault mode and the
status indicator lights up
according to the fault state
(see chapter on Fault
diagnosis)
(Optional, only for units with
+ 2K)
setp.
The location of the DIP switch on the control board is shown in the
circuit diagram.
The coding options are represented on a display image (Comfort-
and Multi-Controller) or on the circuit diagram (Standard-Controller).
Display image and/or circuit diagram are found on the inside of
the service flap or on the inside of the device hood and are
reproduced on the accompanying sheet.
Starting with a particular set-temperature in the switch cabinet, an
upper limit temperature can be selected which, if exceeded, will
generate an alarm. On units with Comfort- or Multi-Controller, the
lower temperature limit can also be monitored. See accompanying
sheet for factory settings.
CAUTION: Changes to the parameters of the unit set in
the works may be made only by authorised persons!
Isolate the cooling unit from the mains before changing
the DIP-switsch settings. Otherwise the modified settings
won't be accepted.

11 Cleaning and Maintenance

Hazard!
Isolate the cooling unit from the mains before carrying out
any cleaning or maintenance operations.

11.1 Cleaning

The cleaning intervals depend upon the relevant operating
conditions. In particular observe the following instructions.
• Clean the heat exchanger regularly.
• Clean the heat exchanger using a soft brush or pressurized air.
• We recommend that the condensate run-off opening be checked
regularly.
Proceed as follows:
1) Disconnect the cooling unit from the power supply.
2) Remove external cover.
3) Clean heat exchangers
CAUTION:
Protect the electric components against leakage.
CAUTION: Damage to louvres
Do not use any pointed or sharp-edged objects. The ribs
should not be compressed or damaged during the cleaning
process.
CAUTION: Damage to electric connections on the
covering hood
If the covering hood is removed, the electric plug-in
connections on the inside must be removed by hand. During
fitting do not forget to plug-in!
• If the cooling units are provided with a front filter clean the filter
mat regularly. The cleaning intervals or the intervals for replace-
ment of the filter mat mainly depend upon ambient conditions
(air pollution).
• You can rinse the filter mat using water heated to 40 °C and
commercially available mild detergent. It is possible to remove
any dry dirt by knocking the mat slightly, vacuum cleaning it or
blowing it out.
CAUTION: Damage to the filter mat.
Do not wring the filter mat. Avoid too solid a water jet.
• If the filter mat is oily or greasy, replace.
11.2 Maintenance
The cooling circuit, as a maintenance-free, hermetically sealed
closed system, is filled at the factory with the necessary coolant,
checked for leakages and is subjected to a functional check run.
The cooling unit is largely maintenance-free. The components around
the external air circuit require maintenance and cleaning depending
upon the ambient conditions (see Section 11.1).
085 408 064c