Dust - Hitachi GR2000 Series Installation Manual

Dust conditions for this router must meet the criteria of Table 5-2 in falling-dust
measurement or floating-dust mass density measurement. A sample process of
falling-dust measurement is shown in Figure 5-1.
When the measured value exceeds the acceptable range, and when the conductor
and insulator are heavily covered in dust, appropriate protection, such as shortening
of the periodic inspection cycle, addition of a dust-proof case, and air purification are
required depending on the humidity of the installation site.
Table 5-2 Dust Requirements
Environmental Item

Dust

Falling-Dust Measurement (%/W)
5 or below
Floating-Dust Mass Density
Measurement (mg/m
0.15 or below
Light
Source
3
)