Hỗ trợ trực tuyến
Liên kết website

Standard of Cable Tray Scale

Chia sẻ :

NEMA VE 1 TESTING METHODS 
 
Compliance with these standards is not regulated by NEMA or any other U.S.-based entity as required by the National Electronic Code (NEC). This standard is a recommendation for cable trays. Cable tray manufacturers can test their products in an independent laboratory to suit this standard. However, in Canada, this standard is mandatory compliance like the NEC in the United States. Some important aspects of the NEMA VE 1 standard:
  1. Power factor and safety load The safety load is determined based on the results of testing a series of cable ladders. Tests must be conducted at the same length and on different lengths with a safety factor of 1.5 to determine the load leading to broken elevator. In this way, the load is determined based on the average performance of the samples in many trials and is well calculated.
   2. Noise The NEMA VE 1 standard does not specify any limitation on the deflection of cable support components. Therefore, it will definitely need a thorough design system.
   3. Resistance Connector The resistance of the connections is limited to a maximum of 330 mΩ.
The NEMA VE 1 rating is based on the Imperial 1 measurement system. The numbers represent the length of the ladder lift: 8 = 8ft (2.4m) 12 = 12ft (3.6m) 16 = 16ft (4,8 m) 20 = 20 ft (6,0 m) 2. Letters indicate the type of work load. A = 50lbs / lin.ft (75kg / m) B = 75lbs / lin.ft (112kg / m) C = 100lbs / lin.ft (149kg / m)
   Example: A 20B ladder lifter requires a minimum working load of 75 lb / ft on a 20ft (ie, 112kg / m in about 6.0m).
NEMA Test Method According to NEMA VE-1 / CSA 22.2, there are two methods of testing the load of the cable tray (Safety Factor 1.5): • Load leading to destruction: Damage load / 1.5 = load capacity factor = test load • Load remaining deflection: 1.5 x length x load factor = test load after 15 minutes when total test load is removed, deflection the rest is measured.
 
To ensure the quality of construction works and bring confidence to customers, we - Viet A Equipment Joint Stock Company has put the products of cable trays in their trials and has met the standards NEMA VE1.

---------------------------------------------