The cable has a long continuous length, no joints in the middle, good flexibility, fire resistance (950℃, 3h), smoke-free, non-toxic, corrosion-resistant, aging resistance, radiation resistance, high temperature resistance, rodent bite resistance, and can automatically eliminate spontaneous combustion Destruction of power and electric power, long service life.

Cable superiority 

1. Excellent fire resistance. The fire resistance level not only meets the international GB12666.6A class 950℃, 90min, but also meets the British BS6387-1994 A class 650℃3h; B class 750℃3h; C class 950℃3h Requirement; At the same time, it can withstand water spray and mechanical impact during combustion;

2. The continuous length is long, whether it is a single-core or multi-core cable, its length can meet the needs of power supply, and each continuous length can reach more than 1000m;

3. Large cross-section, single-core cable cross-section up to 630 mm², multi-core cable cross-section up to 70 mm²;

4. Flexible, the cable can be coiled on the cable reel, with a bending radius of 6-10D, (D is the outer diameter of the cable);

5. It is smoke-free and non-toxic when burned. Inorganic materials (non-combustible) are used for insulation. It will not produce any harmful gas during combustion, and it will not cause secondary pollution. It can be called an environmentally friendly green product;

6. Large overload capacity, the cable not only has a large current carrying capacity, but also has a large overload capacity. According to the wiring instructions, the surface temperature of the cable is usually <70°C. If the wiring is not touchable or in contact with combustible building materials, the temperature of the cable sheath can be increased to 105°C. The long-term working temperature of the fireproof cable can reach 250℃ when overloaded,

7. Corrosion-resistant, organic insulated fire-resistant cables sometimes need to wear plastic or iron pipes, plastic pipes are easy to age and become brittle, iron pipes are easy to rust, and fire-resistant cables have copper sheaths that do not need to be broken down, and copper sheaths are resistant to corrosion good.

8. No electromagnetic interference, when fire-proof cables and information and control wires are laid in the same shaft, they will not interfere with the information transmitted by the signal and control wires and cables under the shield of the copper sheath;

9. The safety is good. The fireproof cable can supply power normally in the flame, start the fire extinguishing equipment, reduce the fire loss, and is particularly reliable for personal safety. Its copper sheath is a good conductor and is the best grounded PE wire, and Continuous to the full length of the cable, greatly improving the sensitivity and reliability of grounding protection;

10. Long service life. Inorganic insulating materials are resistant to high temperatures and are not easy to age. Their service life is many times longer than that of organic insulated cables. Under normal working conditions, their service life can reach more than 100 years;

11. Good economy. Flexible fireproof cables have advanced manufacturing technology and simple installation. Under the same conditions, their overall costs are significantly lower than those of mineral insulated cables;

I. Inorganic mineral insulated cable manufacturing standards

JG/T313-2014 rated voltage 0.6/1kv, and metal sheathed inorganic mineral insulated fireproof cable.

Second, the characteristic standard of mineral insulated cables:

1. BS6387: 1994 performance standard for cables to keep circuits intact under fire conditions (UK)

2, GA306.1～306.2-2001 Ministry of Public Security Fire Standards

3, IEC60332-3 cable burning test under flame conditions

4, GB/T18380.1-.3-2001 cable burning test under flame conditions

5. Determination of smoke density of GB/T17651.2-1998 cable or optical cable burning under specific conditions

6, GB/T17650.2-1998 The test of gas evolution when the material taken from the cable burns

7, GB/T19216-2003 Test method for fire resistance characteristics of wires and cables

8. IEC60331 test method for fire resistance characteristics of electric wires and cables

9. UL2196 cable fire resistance test (United States)

10, IEC60754-2 acid and corrosive gas volatilization

11, IEC60134-2 smoke density test

12, GB31247 Cable and optical cable burning performance classification

Explanation of RTTZ series flexible fireproof wire and cable current capacity:
The continuous load carrying capacity (rated flow) of the wire and cable is an important and complex physical quantity, and the samples of each manufacturer are almost different. Internationally, there are many different factors, which are difficult to explain, but everyone at home and abroad has one thing in common: they all follow the IEC international standards. The company fully refers to the IEC287 standard to determine the ampacity of flexible waterproof wires and cables. The basis is that the ambient temperature is 40°C and the core temperature is 90°C. Due to the excellent high temperature resistance of inorganic insulated wires and cables, can it increase the core temperature, reduce the load surface, and save investment? Of course, it is not recommended by the company alone, because doing so will greatly increase the copper loss and benefit from comprehensive economic benefits. It seems to be cost-effective.

Design Reference

1. Single-core cable and multi-core cable selection

Because the cost performance of multi-wire cables is much better than single-core cables, multi-core cables should be preferred if the working current is less than 300A, and single-core cables should be used for larger cross-sections of 185 mm² and above.  

2. Cable current carrying capacity

The current-carrying capacity of RTTZ cables was stipulated in GB/T16895.15 in the morning, which is reliable. Special reminder, in order to reduce the cost, increase the current carrying capacity, and reduce the conductor cross-section to 1-2 grades, as long as two conditions are met: first, the installation site is safe, and second, the terminal pressure drop requirements are met.  

3, terminal pressure drop calculation
The voltage drop requirement at the end of the cable is specified in the specification (±5%). You can use the simple calculation formula △U=K*I*L*Vo(V) single-phase K=2: three-phase K=√3.
Example 1  Multi-core cable RTTZ-3×70=1×35, cable length 80m
         Calculate current 1=200A    Try to find the terminal voltage drop
         Solution K=√3, Vo=0.59V/A*Km=0.00059V/A*m
         get △U=1.73×200×80×0.00059=16.3V  meet the requirements of the specification.
Example 2  Single-core cable RTTZ-3 (1×240)+1×120, the cable length is 150m
         Calculate current 1=600A
         Solution K=√3, Vo=0.10V.A*Km=0.00010V/A*m
         get △U=1.73×600×150×0.00010=15.57V  meet the requirements.
4. Checking calculation of dynamic thermal stability of cables

RTTZ cable not only has high temperature resistant inorganic insulation, but also has a certain degree of flexibility. It does not need to check the dynamic thermal stability.  

5. Anti-corrosion

The copper sheath and inorganic insulating materials of RTTZ cables have good corrosion resistance, and there is no need to consider anti-corrosion measures in general places. If it is installed underground or in a place with strong corrosive gas, it should be marked that the cable has a PVC protective sheath.  

6. Cable grounding

The copper sheath of the RTTZ cable is a good PE wire, and the common wear surface meets the requirements of the standard. Four cores can replace five cores of organic insulated cables, saving investment. One end of the copper sheath of a multi-core cable should be grounded, and both ends of the copper sheath of a single-core cable should be grounded. When single-ended grounding is used for energy saving, the other end must be electrically insulated. The copper sheath can have multiple grounding points.  

7. Branch box and pre-branch cable

In the trunk-type power distribution system, branch boxes or pre-branched cables can be used. The main cable does not need to be disconnected (to reduce the point of failure), but the cable must be covered with a support, eliminating the need for bridges.  

8. Cable accessories

RTTZ cables are provided with terminal connectors. According to installation needs, terminal connectors and intermediate connectors can also be made on-site. For large cross-section multi-core cables, you can add an intermediate connector. The fire resistance characteristics of the connector are the same as this one. . In order to reduce the difficulty of installation when the cross-section cable is bent, various prefabricated bending joints can be matched. The intermediate joint can also have multiple grounding points.  

9. Calculation of the design length on the cable

RTTZ cable has a certain degree of flexibility, which can automatically eliminate the damage of natural force and electric power, and there is no need to add S and U-shaped connectors at a certain distance. A serpentine shape is naturally formed in the radiation and a certain length is required for the cable head, so the additional length is increased by 1.5m-2m  

10. Cable laying
The cables can be directly covered and bridges are omitted. Multi-core cables can pass through the embedded iron pipes of the floor slab and can be fixed with iron fixtures. For single-core cables, it is strictly forbidden to wear a single iron pipe and tie them with high-permeability closed materials.

11. Cable bending radius

Note: 1. When the cable adopts a tightly compressed core, the diameter of the conductor should be 95% of the nominal diameter; the outer diameter of the metal sheath will be adjusted accordingly to make it smaller. When the insulation is reinforced, the outer diameter of the cable increases by about 5%.
       2. Special large-size 2-core or 3-core cable, in order to reduce the outer diameter of the cable, the conductor core can be semi-circular or sector-shaped, or 2 single-core cables can be used.
       3. The thickness of the embossed copper sheath will be appropriately thinner, but it should meet the electrical performance requirements as PE; if the copper sheath is not required for PE wire, only its mechanical strength must be guaranteed .

Note: * means that the main conductor adopts a sector shape, the fourth core conductor adopts a circular compression, and a single-core cable should be used for multi-core cables of 95 square meters and above.

Note: 1.3+1 core is a special cable, and the 20℃ copper sheath resistance is calculated according to the following formula: R20=0.0178÷π*4÷[D²-(D-2h)²]*1000
Where: D- cable outer diameter; h- cable copper sheath thickness

Cable laying

RTTZ cables can be directly covered and bridges are omitted. Multi-core cables can pass through the embedded iron pipes of the floor slab and can be fixed with iron fixtures. For single-core cables, it is strictly forbidden to wear a single iron pipe and tie them with high-permeability closed materials.  

Precautions for RTTZ cable installation

1. The RTTZ cable installation method is the same as that of ordinary cables. It does not require professionals or installation training. Follow the installation and construction essentials and precautions provided by the manufacturer. The manufacturer can send someone to guide you before installation.

2. The cable reel goes directly to the site for payout, and the payout can be from bottom to top, or from top to bottom.

3. Cable bracket and fixing

a Horizontal hanger allowable span 1) cable outer diameter≤20mm, allowable span 400mm; 2) cable outer diameter>20mm, allowable span 800mm;

b Allowable span of vertical support 1) Cable outer diameter≤20mm, allowable span 1500mm; 2) Cable outer diameter>20mm, allowable span 1000mm;

c Laying in the cable tray, the allowable span of the fixed cable can be referred to items a and b;

d A natural serpentine shape is allowed when the cable is laid, and the single-bending convexity should be ≤2D, and D is the outer diameter of the cable;

e It is strictly forbidden to use magnetic materials, such as iron wires, for the fixing of single-core cable ties;

f Wires and cables cannot pass through a magnetic tube or closed magnetic components of any shape. When they must pass through steel pipes (such as basement to floor), they cannot pass through three-phase and four-wire together. Each steel pipe should be sawn open. Only a seam can pass through.

4. Cable accessories

a Intermediate connector  Extra-long cable or large cross-section multi-core cable (a single heavier weight can be divided into two sections) with a connector in the middle and field connection. The fire resistance level is equal to the main body;

b Right-angle elbow  When the cable is laid in a right-angle turn, it is difficult to bend on site. Prefabricated right-angle elbow joints can be equipped to facilitate on-site construction;

c Terminal connector  According to user needs, it can be equipped with terminal connectors or not accompanied by terminal connectors. When making the terminal head on site, strip off the copper sheath, and strip the end of the insulation about 30mm compressed terminal. Use a megohmmeter to check the insulation resistance between the copper sheath and the conductor. After passing the test, put on a heat-shrinkable tube to protect the unstripped insulation;

5. Cable bending

When the cable is bent, a round wheel gasket with a diameter of not less than 0.5m must be used, and an arc gasket must also be used for bending.

6. Cable segmentation

On-site cables can be divided according to requirements at will, no need to use blowtorch to test.

7. Cable grounding

a There is no special requirement for one or more grounding of the copper sheath of the multi-core cable;

b The copper sheath of a single-core cable should be grounded at both ends (multiple ends are also available). If energy-saving single-ended grounding is required, the other end must be insulated to prevent people from touching it and prevent combustible materials around the cable;

c Cable grounding can be made of copper tape, the copper card is fastened on the copper sheath, and the copper conductor is used to guide the grounding point. If titanium clamps are used, they must be galvanized and plated.

8. Power on the cable

a No. terminals have been made at both ends of the cable. Before connecting to electrical equipment, a gigavolt megohmmeter must be used to test the insulation resistance. Single-core cable detection between conductor and copper sheath, multi-core cable detection, between phase line and phase line, between phase line and neutral line, between phase line and copper sheath, neutral line and copper sheath between.

b The two ends of the cable are connected to the electrical equipment, and the insulation resistance of the system is measured by a kilovolt megohmmeter on the entire system. Only when ≥0.5MΩ can it be powered on.

9. Transportation and storage

a. During transportation, the cable must not be affected by mechanical impact, rain and snow, and moisture;

b. The cable should be stored in a dry warehouse, and there should be no harmful substances or atmosphere that damage the cable in the warehouse;

c. The cables at the construction site should be placed in a dry place;

d. After the construction is completed, the ends of the remaining cables should be reliably sealed.

RTTZ mica tape mineral insulated copper sheathed power cable has an important role in protecting life, materials, and information security. It is used in trunk lines, consumer lines, escape rescue systems, such as emergency lighting, fire detection, alarm systems, elevator systems, Smoke exhaust system, and control circuit, etc.

      1. High-rise buildings

　　 general lighting, emergency lighting, fire alarm, fire-fighting electrical wiring, emergency elevator and lifting equipment wiring, computer room control wiring, main/sub-main power distribution system wiring, dual power control wiring.

       2, airport terminal

　　 General lighting and power supply, emergency lighting, fire monitoring system, fire alarm system, fire electrical wiring.

       3, subway, light rail, tunnel

　　 general lighting, emergency lighting, fire alarm, fire-fighting electrical wiring, ventilation wiring and life-saving system.

       4, shopping centers, hotels, hospitals

　　 general lighting, emergency lighting lines, emergency broadcasting lines, emergency elevators, fire fighting lines and lifting equipment lines.

　　5, conference center, sports center, theater

　　 general lighting, emergency lighting lines, emergency broadcasting lines, emergency elevators and lifting equipment lines.

       6, libraries, museums, data processing centers

　　 general lighting, emergency lighting lines, fire alarm control lines, fire-fighting electrical lines.

　　7, parking lot, underground garage, air defense

　　 general lighting, emergency lighting, fire alarm, fire fighting lines and ventilation lines.

   　8. Places of interest

　　 general lighting, emergency lighting, fire alarm, fire-fighting electrical wiring.

       9, petrochemical, petroleum platform

　　 general lighting, emergency lighting lines, high-temperature places, fire-fighting lines, high-power lines, lines in potentially dangerous explosive areas.

      10. Warships, ships

　　 Power transmission line for generator room, fire monitoring system, fire alarm system, smoke emission and ventilation line, kitchen power line, large power line, dual power control line, emergency lighting, emergency broadcast line, computer room control line.

      11. Iron and Steel Metallurgy

　　High temperature environment power and control lines, emergency power supply, large power lines, power supply lines that cannot be cut off, power transmission lines in the generator room.

      12. Power plant

　　 large power lines, general lighting, emergency lighting, fire alarm, fire-fighting electrical lines.

      13. Power plants, nuclear power plants

　　General lighting, emergency lighting lines, computer room control lines, large power lines, high temperature environment power and control lines, lines in potentially dangerous explosive areas.

　   14、Aerospace

　　General lighting, emergency lighting lines, computer room control lines, large power lines, high temperature environment power and control lines, lines in potentially dangerous explosive areas.

      15, oil depot, ammunition depot

　　 general lighting, emergency lighting, fire alarm, smoke emission, flammable and explosive and ventilation lines.

　   16, industrial and mining

　　 Smoke exhaust fan, high-frequency heating furnace, high-temperature places, fire-fighting lines, large power lines.