Technical data
Installation, user and maintenance manual – AY Condensing line, AY series
53
Figure 5.9
Centre distances of mounting holes for Direct Digital Controller (DDC).
LEGEND
Holes for mounting DDC’s to panel
horizontal: 168 mm
vertical: 158 mm
The DDC's operating temperature range is 0 - 50 °C. If the temperature of the room
where the DDC is installed falls below zero, it continues to operate correctly to -10 °C.
However, its LCD display may not be able to display data.
2) How to supply power to the Direct Digital Controller (DDC)
The DDC requires a low voltage power supply (24 V) with 230/24 V AC, 50/60 Hz safety
transformer; the minimum power requirement is 20 VA.
To power the DDC (o a transformer located in an external panel), proceed as follows
(see example in Figure 5.10 DDC - electric supply → 54):
You will need: the appliance disconnected from the electricity supply; the external
electrical panel congured by the installation technician. Necessary equipment and
materials.
Make sure that the external electrical panel is equipped with a 230/24 V AC - 50/60 Hz
safety transformer, of at least 20 VA power.
Remove the DDC's back panel by undoing the 4 bolts securing it (detail "A" - Fi-1.
gure 5.8 Direct Digital Control (DDC) → 52).
Use an electrical power cord (minimum cross section: 2x0.75 mm2.
2
).
Pass the power cord (DDC side) through the hole in the DDC's cover and hook 3.
up as shown in the example, with the following polarities: terminal 1 = 24 V; ter-
minal 2 = 0 V; terminal 3 = ground.
Terminal 3 of the DDC's 4-pole connector (AL) must be, in any case, connected to a
ground plant (r≤0,1Ω). Terminal 2 of the DDC is connected internally to terminal 3, and
is thus also connected to ground. Make the grounding connection on the transformer
terminal connected to terminal 2 of the DDC. if the transformer already has one wire
grounded, it must be connected to this terminal.
On completion, close the DDC's back panel with the 4 bolts.1.