Hardware manual PCD7.LRxx-PG5 room controller │ Document 27-653; version ENG07 │ 2019-03-21
Saia-Burgess Controls AG
Installation regulations and relay contacts
Appendix
A-4
A
A.3 Installation regulations and relay contacts
A.3.1 Installation regulations for switching low voltages
For safety reasons, voltages of max. 50 V may be switched on this module.
The safety standard concerning clearance and creepage distances between
module.
Note that all connections to the relay contacts of module ..A250 must be connect-
ed to the same circuit, i.e. only one phase is permitted per module. The individual
circuits can be protected by separate fuses.
A.3.2 Switching inductive loads
-
ing problems is impossible. These faults must be minimised as far as possible.
While the Saia PCD
®
is immune to these faults, there are other devices that may
It should also be noted that the EMC standards (EMC Directive 89/336/EC) have
been in force since 1996 as part of the harmonisation of standards within the EU.
Therefore two basic principles can be stipulated:
THE SUPPRESSION OF INDUCTIVE LOADS IS ABSOLUTELY NECESSARY!
FAULTS ARE TO BE CORRECTED AT THE SOURCE OF INTERFERENCE
WHERE POSSIBLE!
The relay contacts on this module are interconnected. Nevertheless, it is a good
idea to connect a snubber to the load.
(Often, these are available as standard components for standardised contactors
and valves.)
When direct voltage is switched, it is strongly recommended to attach a
free-wheeling diode over the load. This is true even if theoretically an ohmic load
is being switched. An inductive proportion can always be found in practice (con-
extended.
Transistor output modules are recommended for direct voltage.
To Next Page
Loading...
Need help?
General
