The difference between BTTRZ cable and BBTRZ cable

The difference between BTTRZ cable and BBTRZ cable

Flexible mineral insulated fireproof cables BBTRZ and BTTRZ are new products without corresponding models corresponding to national standards, and there is only one word difference between the two product models, and the difference between them is often unable to be distinguished at the first contact. So what is the difference between them?

Letter meaning of BTTRZ and BBTRZ models

The origin of BTTRZ

BTTRZ series product structure

At the earliest, the only mineral insulated fireproof cable in my country was the BTTZ series of copper sheathed magnesium oxide mineral insulated cables, which are synchronized with the international standard. The series of cables consist of one or several conductors and compressed oxide cables in the same metal sheath. Compact composition of magnesium powder. Because this product uses Class 1 solid copper rods as conductors, the flexibility of the cable is harder than our commonly used plastic power cables, so it is named "rigid" mineral insulated cables.

It is precisely because of the "rigidity" of BTTZ that my country pioneered the copper sheathed corrugated mica tape mineral insulated structure cable used in the construction field. Because it uses the Class 2 stranded conductor of the plastic power cable, the conductor has a "flexibility" that exceeds BTTZ. In order to create new sales highlights, manufacturers have distinguished them from "rigid" mineral insulated cables by their reputation as "flexible" mineral insulated cables.

Knowing the origin of the above types of cables, then the model distinction is easier. In the naming convention of Chinese cable models, flexible core conductors have always been represented by the first letter "R" in the pinyin of "soft". Therefore, BTTRZ is actually on the basis of BTTZ, adding an R word that we are used to, which represents the "flexible" mineral insulated cable. Later, the Ministry of Housing and Urban-Rural Development of the People’s Republic of China issued the People’s Republic of China Construction Industry Standard JG/T313-2011 "Metal Sheathed Inorganic Mineral Insulated Cables and Terminals with a Rated Voltage of 750V and Below" in 2011 (updated to 0.6/ 1kV), the structure product was determined to be named YTTW. It is a bit embarrassing that in the process of using YTTW, people found that it was seriously inconsistent with our usual naming method, and many people could not accept it. What about our R? In China, flexibility must have R to appear reasonable, right? With a series of calls from the people, the National Standardization Committee finally issued GB/T34926-2017 "Rated voltage 0.6/1kV and below mica tape mineral insulated corrugated copper sheathed cable and terminal", the standard renewed the flexible copper core corrugated copper The sheathed mica tape mineral insulated structure cable is named RTTZ, and many details have been further optimized. So far, this series of mineral insulated cables has the support of national standards and is already in a state of vigorous development. After more than ten years of market test, I believe it will occupy a larger market share in more mature applications.