Mineral Insulated Cable

iSE Mineral Insulated Cable

Mineral insulated cable is also called fireproof or copper-conductor copper sheathed magnesia insulated cable in China, known as MI Cable abroad. Due to the particularity of product material and structure, it has high electric property, mechanical performance, environment resistance and environmental protection that the traditional organic insulation cable does not have. It has been widely applied to the basic industry and civil construction.

Main performance of mineral insulated cable:

  • -   Fire-resistant performance
  • -   Strong overload protection
  • -   Large current carrying capacity
  • -   High working temperature
  • -   Waterproof, anti corrosion and explosion-proof property
  • -   Highest standard for Fire Proof Cable
  • -   Suitable for extreme fire safety measurement
  • -   Continously transmitting electricity after 2 hours of fire disaster at 1000°C

Mineral Insulated Cable Structure

Mi Cable is composed of high-conductivity copper conductor, mineral (magnesium-oxide) insulator and seamless copper tube sheath, if the cable is used in the locations where the copper will be eroded it may be added with plastic sheath (optional) at the outermost layer, The continuous working temperature of bare cable reachs 250°C, it cab supply the power for 3 hours continuously at 950°C - 1000°C, in addition, it can work at copper melting point if 1083°C in short time or unusual time (melting point of magnesia: 2800°C)

Test Item GB/T19216 BS6387 IEC331
Fire-resistant test 750°C
(Class A) 650°C 180min
(Class B) 750°C 180min
(Class C) 950°C 180min
(Class S) 950°C 20min
Water spray test Without (Class W) 650°C 15min Without
Impact test Without (Class X) 650°C 15min
(Class Y) 750°C 15min
(Class Z) 950°C 15min
Fire Resistant test MI Cable
Water Spray test MI Cable
Impact Test MI Cable

Supplement: all the test requirement including S6387 are not strict enough, S6387 requires that 3 types of test to be carried out on three new samples respectively, which is incomformity with the actual fire condition, cable fire safety test of British Underground Corporation requires that all the test should be carried out on one sample, 950°C for 3 hours, use steel bar to impact once every 10min, spray with water for 15min (steel bar keeps striking), then bend the sample for 180° at the struck point, make further mechanical shock.

Comparison of the performance

Comparing the performance BTTZ
Mineral Insulated Cable
BTTZ type
Common fire-retardant and fire resistant cable
ZN-YJV type
LSZH fire resistant cable
WDZN-Y JY type
Cable specs. 4 x 120 4 x 150 + 1 x 70 4 x 150 + 1 x 70
Layout conditions Surface wiring is available, without tray or pipeline need enclosed tray or pipeline protection need enclosed tray or pipeline protection
Service life Over 100 years 20 - 40 years 20 - 40 years
Fire-retardant performance No combustion CAT-C fire retardance CAT-C fire retardance
Fire-resistant performance 950°C 180min Cable may be burned at 750°C for 90min, its price will be increased greatly.
Fire - resistant capability Water spraying test Meeting the test requirements Fail to pass this test
Mechanical impact Meeting the test requirements Fail to pass this test
Temperature resistance performance Normal : 250°C; max : 1000°C Max : 90°C; short circuit : 250°C
Environmental protection performance No smoke, halogen or poison Producing a great number of smoke and poisonous gas in burning Producing little smoke or poisonous gas in burning
Occupying the space ⌀ 34mm ⌀ 55mm ⌀ 65mm

Comparison of the price

Comparing the performance Mineral Insulated Cable
BTTZ type
Common fire-retardant and fire resistant cable
ZN-YJV type
LSZH fire resistant cable
WDZN-Y JY type
Cable specs. 4 x 120 4 x 150 + 1 x 70 4 x 150 + 1 x 70
Current carrying capacity 380 360 365
Price per meter (percentage) 100% 95% 102%