19
The k-value depends on the fan size used. This value can
be found in the table below.
k-values
Fan size
Plug fan
225
47
250
60
280
75
315
95
355
121
400
154
450
197
500
252
560
308
630
381
710
490
4.10.2 - Frequency converters
It is recommended to install a frequency converter with an
integrated operating switch. If a separate operating switch
is installed on the unit and near the frequency converter,
this can be located in the supply voltage for the frequency
converter. If the frequency converter is not installed near
the unit/operating switch, the operating switch can be
placed in the control power circuit, that switches the supply
voltage to the frequency converter via a relay. To connect
the frequency converter, please refer to the wiring diagram
for the converter installed. Ensure that the EMC directives
are observed and pay attention to the shielded cables.
The frequency converter must always be correcly set to
suit the motor and type installed. Observe the instructions
of the supplier of the frequency converter. Special attention
should be given to the following parameters:
• Correct application of the general motor data
-
Pay special attention to the motor frequency.
-
For subsynchronous operation (lower than the
network frequency) it must be set in accordance
with the motor nameplate.
-
For supersynchronous operation (higher than the
network frequency) it must be set for the
maximum admissible frequency of the motor/
impeller assembly (this applies above all to plug
fans.)
• Operating type, square variable connection
• It is recommended to cut out so-called overmodulation
• Setting of the normal start-up/shut-down times.
• Check for possible condensate/moisture. Condensate
may form in the period before the first start-up of the
AHU as a result of weather change and/or humid air
from the building. Remove all condensate from the
construction components and dry the electrical
components using warm (dry) air (e.g. with a hair
drier).
• Do not work on electrical components including
control panels, switches, VFD untill you are sure ALL
POWER IS OFF and no resudual voltage can leak from
capacitors or solid state components. Lock open and
tag electrical circuits during servicing. If work is
interrupted, confirm that all circuits are deenergized
before resuming work. Risk of injury or death by
electro shock. High voltage is present on motor leads
even though the motor is not running when a VFD is
used. Open the power supply disconnect before
touching motor leads or terminals.
Please ensure that the duct silencers are always correctly
supported on the floor or suspended from the ceiling.
Make sure that the following weights are taken into
consideretion:
Duct silencers
Unit type
Weight, kg
0405
30
0506
35
0606
45
0707
50
0808
70
0909
75
1010
105
1111
110
1212
135
1412
170
1416
230
The duct silencer can also be used for units installed
outside. After installation they must always be insulated on
the outside to ensure that they are water- and steam- light.
The pre-installed air intake and discharhe hood (if used)
must be removed first. Install the corner frame, supplied
separately, at the opening og the silencer, before installing
the silencer. Finally replace the air intake and discharge
hood at the opening of the silencer. Here too the duct
silencer must be sufficiently supported, as show in the
drawing below.
4.12 - Lighting
• Check the connection voltage.
•
Check the operation of the switch. The switch must be
connected in accordance with local regulations.
4.11 - Silencers
The silencers for the 39SQ are supplied separately on a
pallet as duct silencers. For this use the connection profiles
recommended and use the method described in chapter in
4.1.5 - “Duct connections”. The connection to the rest of
the duct system can also be made in this way, as show in
the drawing below.
