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5 Connecting to power supply
SOLITRAC 31 • Profibus PA
43834-EN-211203
5 Connecting to power supply
5.1 Preparing the connection
Always keep in mind the following safety instructions:
•
The electrical connection must only be carried out by trained,
qualified personnel authorised by the plant operator.
•
If overvoltage surges are expected, overvoltage arresters should
be installed.
Warning:
Only connect or disconnect in de-energized state.
Note:
Install a disconnecting device for the instrument which is easy to
access. The disconnecting device must be marked for the instrument
(IEC/EN 61010).
The instrument is designed in protection class I. To maintain this
protection class, it is absolutely necessary that the ground conductor
be connected to the internal ground terminal. Take note of the national
installation regulations.
Supply voltage and signal output are carried on separate connection
cables if reliable separation is required. The supply voltage range can
differ depending on the instrument version.
The data for power supply are specified in chapter "
Technical data
".
General requirements
•
Make sure that the cable used has the required temperature resist-
ance and fire safety for max. occurring ambient temperature
•
Use cable with round cross section for instruments with housing
and cable gland. To ensure the seal effect of the cable gland (IP
protection rating), find out which cable outer diameter the cable
gland is suitable for.
•
Use a cable gland fitting the cable diameter.
•
Unused cable glands do not offer sufficient protection against
moisture and must be replaced by blind plugs.
Voltage supply
For power supply, an approved, three-wire installation cable with PE
conductor is required.
Signal cable
Use for the signal output a cable according to the respective bus
specifications.
Metric threads
In the case of instrument housings with metric thread, the cable
glands are screwed in at the factory. They are sealed with plastic
plugs as transport protection.
You have to remove these plugs before electrical connection.
Safety instructions
Voltage supply via mains
voltage
Select connection cable
Cable glands