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Siemens
VAV compact controller KNX/PL-Link G..B181.1E/KN
CE1P3547en
Building Technologies
2017-03-23
7
Safety and EMC optimization
7.1 Safety
notes
This section contains general regulations and the regulations for mains and
operating voltage. It also provides important information regarding your own safety
and that of the entire plant.
The warning triangle to the left means that observance of all relevant regulations
and notes is mandatory. If ignored, injury to persons or damage to property may
result.
Observe the following regulations during engineering and project execution:
∂
Electrical and high-voltage directives of the respective country
∂
Other country-specific regulations
∂
House installation regulations of the respective country
∂
Regulations issued by the utility
∂
Diagrams, cable lists, disposition drawings, specifications and instructions as
per the customer or the contractor in charge
∂
Third-party regulations issued by general contractors or building operators
The electrical safety of building automation and control systems supplied by
Siemens depends primarily on the use of
extra low-voltage with safe isolation
from mains voltage.
Depending on the type of extra low-voltage earthing, a distinction is to be made
between SELV and PELV as per HD 384, “Electrical plants in buildings“:
Unearthed
=
SELV
(
S
afety
E
xtra
L
ow Voltage)
Earthed
=
PELV
(
P
rotective
E
xtra
L
ow
V
oltage)
Observe the following for grounding G0:
As a rule, earthing and non-earthing of G0 is permissible for AC 24 V operating
voltage. Decisive are the local regulations and customary procedures. For
functional reasons, earthing may be required or not permissible.
AC 24 V systems should always be earthed
if this does not contradict the
manufacturer’s specification.
To avoid earth loops, systems with
PELV may only be earthed at one point of
the system,
normally by the transformer, unless otherwise specified.
Safety note
General
regulations
Safety
SELV, PELV
Earthing of
G0 (system neutral)
Recommendation on
earthing G0