9.1.14 Repainting
WARNING
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:
– IIA, IIB: Total paint coating thickness ≤ 2 mm
– IIC: Overall coating thickness ≤ 0.2 mm for motors of group II (gas)
● Limit the surface resistance of the paint used:
– Surface resistance ≤ 1 GΩ for motors of groups II and III (gas and dust)
● Charge transfer limit
– 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)
● 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.
Maintenance
9.1 Inspection and maintenance
SIMOTICS TN Series N-compact 1PQ8
120 Operating Instructions 11/2018