Technical data

19
• DOK-DIAX02-DDC01******-PRJ1-EN-E1,44 • 01.97
3. Electrical Connections - Installation Guidelines
Fig. 3.4: Power supply cable for a DDC 1.2
3.5. Transformers
Transformers for installation in control cabinets (IP 00) and transformers in
housing with protection category IP 55 are available for adapting the mains
voltage to the DDC 1 connecting voltage.
Autotransformers are preferred for adapting voltages (see section 3.3).
Their protection category is IP 00, and their ambient temperature 40°C.
See section 3.6 for available options.
For special mains conditions, isolating transformers are recommended (see
section 3.3).
Protection category is IP 00; ambient temperature 40°C.
See section 3.7 for available options.
Autotransformers are preferrably used for adapting voltages (see section 3.3).
Transformers in the housing permit a decentralized installation. This decreases
the power loss in the control cabinet.
If transformers are built into the housing, then the surface of the housing limits
the acceptable loss of power. DST ... /G/ type transformers have been
especially constructed with a high level of protection for operation within the
housing. See section 3.8 for available options.
200
mains side
(transformer
side)
device side
L1
1
A
L2
2
B
L3
3
C
PE
yel/gn
D
INS172 or
INS108 with
DDC1.2-N050C
SBDDC1
Autotransformers for
installation in a control
enclosure
Isolating transformers
for installation in a
control enclosure
Autotransformers in IP
55 housing