Grounding And Overvoltage Protection - Siemens Simatic RTU303xC Series Operating Instructions Manual

Table 3- 2
Step
3.6

Grounding and overvoltage protection

Ground/chassis ground concept
Grounding by trained specialist personnel
Have trained specialist personnel create a grounding and chassis ground concept.
Only allow trained specialist personnel to perform the ground connection on the system.
Keep to the local regulations and those that apply to the system. However it is installed, the
housing of the RTU must be grounded to comply with the local electrotechnical regulations
that apply in the relevant country. The most effective grounding method is a direct
connection to ground with minimum resistance.
Do not ground the RTU using the grounding terminal X10.
Instead, ground the protective housing at the connector intended for this. Ground the
housing with a maximum of 1 ohm resistance from the protective housing to ground. For
information on grounding, refer also to the appendix Protective housing (Page 370).
Overvoltage protection
NOTICE
Protection of the RTU and the system
Via cables, leaving the RTU, the coupling in of strong electromagnetic pulses on the supply
cables is possible, for example, resulting from lightning strikes.
The connectors of the RTU are not protected against strong electromagnetic pulses. For
this, external overvoltage protection modules are required.
Have trained specialist personnel create and overvoltage concept that meets the
electrotechnical regulations in the relevant country.
RTU303xC
Operating Instructions, 06/2019, C79000-G8976-C382-06
Procedure for installation
Execution
1 When using the extension board, remove the co-
vers:
1. Insert the tip of a slotted screwdriver in the gap
above the cover.
2. Lever the cover carefully out of its holder.
2 Insert the extension board into the slot from above
until you hear it click into place.
CAUTION
Connecting up, installation, commissioning
3.6 Grounding and overvoltage protection
Notes and explanations
Recommendation: Store the cover in
a safe place in case it needs to be
used later.
73