Digisol DG-GS4200 Series, Руководство по установке, Страница: 10 / 19

DG-GS4200 Installation Guide
2-2
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 installation 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 are shown below:
Temperature: Relative humidity
Long term
condition
Short term
condition
Long term
condition
Short term
condition
15
～
30°C -10
～
50°C 40
～
65
％
5%
～
95%
Table 2-3 Environmental Requirements: Temperature and Humidity
Caution!
A sample of ambient temperature and humidity should be taken at 1.5m above the
floor and 0.4m in front of the switch rack, with no protective panel covering the front and
rear of the rack. Short term working conditions refer to a maximum of 48 hours of
continued operation and an annual cumulative total of less than 15 days. Formidable