Gases; Dust - Danfoss VLT CDS 803 Manual

VLT® Compressor Drive CDS 803
Design Guide
EXTREME AMBIENT CONDITIONS
Hot or cold temperatures compromise unit performance and longevity.
-
Do not operate in environments where the ambient temperature exceeds 55 °C (131 °F).
-
The drive can operate at temperatures down to -10 °C (14 °F). However, proper operation at rated load is only guaranteed at
0 °C (32 °F) or higher.
-
If the temperature exceeds ambient temperature limits, extra air conditioning of the cabinet or installation site is required.

5.3.1 Gases

Aggressive gases, such as hydrogen sulfide, chlorine, or ammonia, can damage electrical and mechanical components of a drive.
Contamination of the cooling air can also cause the gradual decomposition of PCB tracks and door seals. Aggressive contaminants
are often present in sewage treatment plants or swimming pools. A clear sign of an aggressive atmosphere is corroded copper.
In aggressive atmospheres, restricted IP enclosures are recommended along with conformal-coated circuit boards.
The electronic components are, as standard, coated as per IEC60721-3-3, class 3C2. For harsh and aggressive environments, coating
as per IEC60721-3-3, class 3C3 is available.
Table 12: Conformal Coating Class Ratings
Gas type Unit
Sea salt n/a
Sulfur oxide mg/m
Hydrogen sulfide mg/m
Chlorine mg/m
Hydrogen chloride mg/m
Hydrogen fluoride mg/m
Ammonia mg/m
Ozone mg/m
Nitrogen Oxides mg/m
Maximum values are transient peak values and are not to exceed 30 minutes per day.
1
Refer to 7.1 Drive Configurator

5.3.2 Dust

Installation of drives in environments with high dust exposure is often unavoidable. Consider the following when installing drives in
such environments:
• Reduced cooling.
• Cooling fans.
• Periodic maintenance.
Reduced cooling
Dust forms deposits on the surface of the device and inside on the circuit boards and the electronic components. These deposits act
as insulation layers and hamper heat transfer to the ambient air, reducing the cooling capacity. The components become warmer.
This causes accelerated aging of the electronic components and the service life of the unit decreases. Dust deposits on the heat sink
in the back of the unit also decrease the service life of the unit.
38 | Danfoss A/S © 2021.05
N O T I C E
3C1
Value Mean value
None Salt mist
3
0.1 0.3
3
0.01 0.1
3
0.01 0.1
3
0.01 0.1
3
0.003 0.01
3
0.3 1.0
3
0.01 0.05
3
0.1 0.5
for ordering the correct protective rating.
Class
3C2
Maximum value Mean value
(1)
Salt mist
1.0 5.0
0.5 3.0
0.3 0.3
0.5 1.0
0.03 0.1
3.0 10
0.1 0.1
1.0 3.0
Mechanical Installation
Considerations
3C3
Maximum value
(1)
10
10
1.0
5.0
2.0
35
0.3
9.0
AJ330233902305en-000201 / 130R0596