2-2
Table 2-1
Operating environment
Item
Description
Operating temperature
0°C to 45°C (32°F to 113°F)
Relative humidity (noncondensing)
10% to 95%
Requirements on Cleanness
Dust is a hazard to the operating safety of the access controller. The dust accumulated on the chassis
can be adsorbed by static electricity and result in poor contact of metal connectors or metal contact
points. Especially, when the relative indoor humidity is low, electrostatic adsorption is more likely to
happen. This can not only shorten the service life of the access controller but also cause
communications failures. The following table lists the dust concentration limit.
Table 2-2
Dust concentration limit in the equipment room
Physical active substance
Concentration limit (particles/m
3
)
Dust
≤
3 × 10
4
(No visible dust on the tabletop over
three days)
Note: The dust particle diameter is
≥
5
μ
m
Besides the dust specifications, the equipment room of the access controller also needs to strictly meet
the requirements on the concentration of salt, acid and sulfide. These harmful gases can accelerate the
metallic corrosion and the aging process of some parts. The specific limits of the harmful gases such as
are given in the following table.
Table 2-3
Limit on harmful gases in the equipment room
Gas
Maximum concentration (mg/m
3
)
SO
2
0.2
H
2
S 0.006
NH
3
0.05
Cl
2
0.01
Anti-Static Requirements
Generation and damage of static electricity
In the communication network to which the WX5004 is connected, static induction of the access
controller mainly comes from the following sources:
z
External electric fields, such as outdoor high-voltage transmission lines or thunderbolts.
z
Internal environment like flooring materials or the structure of the overall system.
Although the WX5004 is designed to be Electrostatic Discharge (ESD) preventive, excessive static
electricity may enormously damage the card circuits or even the whole device.
