DG-GS4526P Installation Guide
10
In addition, salt, acid and sulfide in the air are also harmful to the switch. Such
harmful gases will aggravate metal corrosion and the aging of some parts. The site should
avoid harmful gases, such as SO
2
, H
2
S, NO
2
, NH
3
and Cl
2
, etc. The table below details the
threshold value.
Gas
Average (mg/m³)
Max (mg/m³)
SO
2
0.2 1.5
H
2
S 0.006
0.03
NO
2
0.04
0.15
NH
3
0.05
0.15
Cl
2
0.01
0.3
Table 2-2 Environmental Requirements: Particles
2.1.1.2 Temperature and Humidity
The switch install site should maintain a desirable temperature and humidity.
High-humidity conditions can cause electrical resistance degradation or even electric
leakage, degradation of mechanical properties and corrosion of internal components.
Extreme low relative humidity may cause the insulation spacer to contract, making the
fastening screw insecure. Furthermore, in dry environments, static electricity is liable to be
produced and cause harm to internal circuits. Temperature extremes can cause reduced
reliability and premature aging of insulation materials, thus reducing the switch’s working
lifespan. In the hot summer, it is recommended to use air-conditioners to cool down the
site. And the cold winter, it is recommenced to use heaters.
The recommended temperature and humidity is shown below:
Temperature: Relative
humidity
Long term condition
Short term condition Long term condition
Short
term
condition
15 ~ 30°C
0 ~ 50°C
40 ~ 65%
5 ~ 95%
Table 2-3 Environmental Requirements: Temperature and Humidity