UL has released a new edition of ANSI/UL 2250, the standard for Instrumentation Tray Cables. This new edition of ANSI/UL 2250 is being issued to revise requirements for metal coverings and is available on the UL website.
1.1 These requirements cover Type ITC instrumentation control cables consisting of two or more current-carrying copper or thermocouple alloy conductors with or without either or both:
a) Grounding conductor(s), bare or insulated, and
b) One or more optical-fiber members, all under an overall jacket.
These electrical and composite electrical/optical-fiber cables are intended for use (optical and electrical functions associated in the case of a hybrid cable) on circuits rated 150 V or less and 5 A or less in accordance with Article 727 and other applicable parts of the National Electrical Code (NEC).
1.2 These cables are rated 300 V but are not so marked. Cables for direct-burial are so marked. Jacketed Type ITC cables comply with one of the following 70,000 Btu/h (20.5 kW) vertical-tray flame tests:
a) The UL test referenced in 35.2.1 – 35.2.2 of these requirements. These paragraphs apply the test method described as the UL Flame Exposure (smoke measurements are not applicable) in the Standard for Vertical-Tray Fire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables, UL 1685.
b) The FT4/IEEE 1202 test referenced in 35.3.1 of these requirements. This paragraph applies the test method described as the FT4/IEEE 1202 Type of Flame Exposure (smoke measurements are not applicable) in UL 1685.
c) For limited-smoke cable, either the UL test or the FT4/IEEE 1202 test referenced in 35.4.1 and 35.4.2 of these requirements. These paragraphs apply the test methods described in UL 1685 with smoke measurements included.
1.3 A cable that contains one or more electromagnetic shields may be surface marked or have a marker tape to indicate that it is “shielded”. A cable that contains one or more optical-fiber members has “-OF” supplementing the type letters and is limited (see 14.3) to carrying optical energy that has been ruled not hazardous to the human body.
1.4 All Type ITC cables qualify for exposure to sunlight (a 720-hour sunlight-resistance test is required – see 29.1). A marking is not required; however, where used, the marking consists of “sun res” or “sunlight resistant” on the tag and either on the overall cable jacket or legible through the jacket [see 42.1(i)].
1.5 These cables may have a metal sheath or armor over the required non/metallic jacket.
1.6 These requirements do not cover the optical or other performance of any optical-fiber member or group of such members.
1.7 The overall jacket on Type ITC cable is a “gas/vapor-tight continuous sheath” in the sense discussed in Sections 501.5 (D) and 501.5 (E) of the National Electrical Code, ANSI/NFPA 70, (see 16.1.1).
1.8 Cables that are surface marked “-ER” are for use as exposed runs of not more than 50 ft (15.2 m) between a cable tray and equipment where the cables are supported and secured every 6 ft (1.8 m).
*Description from the UL Website.
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