RTTZ(YTTW) Flexible Mineral Insulated Cable Product Brief

The RTTZ(YTTW) cable is renamed from the original YTTW cable and has been standardized with the national standard: GB/T34926-2017 "Mineral Insulated Cables with Mica Tape Sheath and Copper Braid Jacket for Rated Voltages of 0.6/1kV and Below." The conductor of the RTTZ cable is made of multi-strand copper绞 wire, insulated with high-temperature-resistant synthetic mica tape mechanically wrapped, and densely filled with alkali-free glass fiber outside the insulation layer. The sheath is made by wrapping copper strips and then welding them into a copper tube, followed by continuous rolling and corrugation forming. For applications where the metallic sheath cannot be exposed, a polyolefin (low smoke, halogen-free) sheath can be added externally.

Product Name & Applicable Voltage

Product Name: RTTZ(YTTW) Cable Products

Rated Voltage:

Model and Specification Range

Model Descriptions and Product Examples

1Product Representation Example

For example:

Copper-core mica tape mineral insulated corrugated copper sheath cable, rated voltage 450/750V, specification 7*1.5mm², indicated as RTTZ-450/750V 7*1.5.

Copper-core mica tape mineral insulated corrugated copper sheath PVC jacket cable, rated voltage 0.6/1kV, specification 4*95m㎡，represented as RTTVZ-0.6/1kV 4*95.

Name and Applicable Voltage

1. RTTZ Cable's Performance and Advantages

Superior fire resistance properties:

The fire resistance rating not only meets the national standard GB12666 but also withstands water spray and mechanical impacts.

Continuous Length:

Whether single-core or multi-core, the cable length can meet the power supply requirements, with each continuous length exceeding 1000m.

Section size large:

Single-core cables can have a cross-sectional area of up to 630mm², while multi-core cables can reach 70mm².

Flexible

Cables can be coiled on drums, with a bending radius of 6-10D.

Smoke and odorless when burning:

Insulation is made from inorganic materials, producing no harmful gases upon combustion and causing no secondary pollution, making it a genuinely eco-friendly green product.

High overload capacity:

Cables not only have a high current carrying capacity but also offer substantial overload capability. According to wiring specifications, the cable surface temperature is typically s70°C. If the wiring is not touchable and does not come into contact with combustible building materials, the cable sheath temperature can be raised to 105°C. During overload, the long-term working temperature of fire-resistant cables can reach 250°C.

Corrosion-resistant:

Excellent shielding performance, copper sheath with good corrosion resistance; in special environments or where copper is prone to corrosion, it is recommended to add an extra layer of low-smoke, halogen-free, or plastic outer sheath over the copper sheath. Under the shielding of the copper sheath, there is no electromagnetic interference, which will not disturb the transmission of information through signal, control wires, or cables.

Good safety performance

Fire-resistant cables can supply power normally in flames (power normally supplied for over 3 hours at 950℃), activate fire extinguishing devices, and reduce fire damage. The copper sheath is an excellent conductor, which can be used as an earthing wire, enhancing the sensitivity and reliability of the earthing wire protection.

Long service life

Withstanding high temperatures and resistance to aging, it boasts a lifespan of over 100 years under normal operating conditions.

Simple transportation and installation:

Flexible fire-resistant cables are easy to transport, install, and have simple installation accessories, similar to standard cables.

Economic performance:

Flexible fire-resistant cables, due to their advanced manufacturing process and easy installation, are more cost-effective than mineral insulated cables under the same conditions.

2. RTTZ Cable Laying and Installation Precautions

1) RTTZ cables can be installed just like standard cables, without the need for special professionals or installation training. In case of necessity, the manufacturer will send technical personnel to assist with installation. Please follow the video tutorial for installing terminal heads and intermediate connectors:

2) Cables can be directly delivered to the site and laid out according to the direction indicated on the cable drum.

3) Cabling Support and Fastening Brackets

a. Horizontal hangers allow span: Cable outer diameter 20mm, span 400mm; Cable outer diameter >20mm, span 800mm; b. Vertical brackets allow span: Cable outer diameter 20mm, span 1500mm; Cable outer diameter >20mm, span 1000mm; c. For cable trays, the allowable span for fixing cables can refer to the above; d. It is strictly prohibited to use magnetizable materials for fixing single-core cables, such as wire; e. Single-core cables cannot pass through magnetizable tubes or closed magnetic components individually; in this case, plastic or resin tubes and components, such as glass fiber trays, can be referenced.

4) Cable accessories, such as intermediate connectors installed on-site, have the same fire resistance level as the main body. When making field terminations, strip the insulation of the conductor at the end by about 300mm, crimp the cable line ferrules, and use a megohmmeter to test the insulation resistance between the copper sheath and conductors as well as between conductors. After passing the test, fit a heat-shrink tube or wrap it securely with insulating tape to protect the fire-resistant insulation layer.

5) When laying cables on-site and encountering turns, they should be bent in a circular arc; twisting and 90-degree bends are strictly prohibited.

6) Ensure the cable is pulled smoothly during installation; strictly prohibit pulling the cable hard when it gets stuck to avoid damaging the copper sheath.

The RTTZ cable series utilizes pre-fabricated branch trunk wiring methods. Both single-core and multi-core cables can be made into pre-fabricated branch cables. Typically, cable manufacturers measure the connection points, main trunk cable, and branch cable lengths on-site to directly process and shape them at the factory. This makes on-site installation and laying straightforward and convenient.