scope:

Description

The enclosures incorporate features to provide for positive drainage, security, and accessibility for monitoring, testing, repairing, and replacing of the components. The enclosures shall provide freeze protection, freeze retardation or non-freeze protection of the components, and be vandalresistant.

Classes

Freeze Protection Enclosures (Heated)

Freeze protection enclosures (Class I and I-V) shall have a minimum thermal resistance value of eight (R8), and a positive means of heat. These enclosures shall be designed and constructed to maintain a minimum internal temperature of 40.0 °F (4.4 °C) using the empirical data obtained in Section 3.6, which is based on an external temperature of -30.0 °F (-34.4 °C). Class I enclosures are designed for components that do not generate positive and/or negative air pressures. Class I-V enclosures are designed for components that generate positive and/or negative air pressures, and include an air inlet and/or outlet.

Freeze Retardant Enclosures (Non-Heated)

Freeze retardant enclosures (Class II and II-V) shall have a minimum thermal resistance value of eight (R8).

These enclosures shall be designed and constructed to be installed in climates where the ambient temperature does not go below 33.0 °F (0.6 °C) for long periods of time. These enclosures offer no guarantee of freeze protection and are for indeterminable temporary freeze protection when the ambient temperature drops below freezing for a short period of time. Class II enclosures are designed for components that do not generate positive and/or negative air pressures. Class II-V enclosures are designed for components that generate positive and/or negative air pressures, and include an air inlet and/or outlet.

Non-Freeze Protection Enclosures

Non-freeze protection enclosures (Class III and III-V) are designed and constructed to provide system security for components when freezing temperatures are not a consideration. Class III enclosures are designed for components that do not generate positive and/or negative air pressures. Class III-V enclosures are designed for components that generate positive and/or negative air pressures, and include an air inlet and/or outlet.

Heat Sources (Class I and I-V)

Heat sources and related equipment supplied by the enclosure manufacturers shall be listed for use in damp or wet locations by an independent third-party certification agency and shall be constructed and installed so that water or other liquids cannot enter or accumulate in or on wired sections, electrical components, or duct work. Heater shall be installed as specified by the manufacturer's installation instructions and local codes.

Drains

Enclosures for use with water conveying systems shall have a means of draining, per Section 3.5.

Access Design

Enclosures shall have a means for accessing the components contained within the enclosures for monitoring, testing, repairing, and/or replacing, per Sections 3.3 and 3.4.

Air Inlets

Class I-V, II-V and III-V enclosures shall have air inlets, per Section 3.1.

Security

Enclosures shall be lockable and vandal resistant.