Repainting; Maintaining Terminal Boxes - Siemens SIMOTICS 1PQ8 Operating Instructions Manual

Maintenance
9.1 Inspection and maintenance
9.1.14

Repainting

Explosion hazard caused by incorrect painting
The paint coat can become electrostatically charged where there is a thick coat. Electrostatic
discharges can occur. There is a risk of explosion if potentially explosive mixtures are also
present at this moment. This can result in death, serious injury or material damage.
You must comply with one of the following requirements when you repaint painted surfaces:
● Limit the total paint film thickness according to the explosion protection group:
● Limit the surface resistance of the paint used:
● Charge transfer limit
● Breakdown voltage ≤ 4 kV for explosion group III (gas and dust)
Suitability test of the paint system for hazardous areas
Proof is available for the electrostatic suitability with explosion-proof machines for the paint
systems ordered by default. Such evidence is not available for paint systems that are non-
standard or specifically requested by customers. Take into consideration that the provided
evidence is not valid for repaintings.
9.1.15

Maintaining terminal boxes

Requirement
The machine is de-energized.
120
WARNING
– IIA, IIB: Total paint coating thickness ≤ 2 mm
– IIC: Overall coating thickness ≤ 0.2 mm for motors of group II (gas)
– Surface resistance ≤ 1 GΩ for motors of groups II and III (gas and dust)
– 60 nC for Group I or Group IIA devices
– 25 nC for Group IIB devices
– 10 nC for Group IIC devices
– 200 nC for Group III devices (values not valid for strongly charge generating processes)
SIMOTICS TN Series N-compact 1PQ8
Operating Instructions 11/2018