NHMC-550A fire-resistant bus duct

NHMC-550A fire-resistant bus ductstructural performance

1. Adopting a reasonable "sandwich" phase line tightly stacked structure design, the bus duct has a compact appearance and small volume, and the bus system has the advantages of low impedance, voltage reduction, and good dynamic and thermal stability.

2. The shell is composed of a mixture of cold-formed thin steel profiles. The side panels on both sides are double layered hollow structures from our factory, which effectively prevent high-temperature gases or open flames from directly entering the interior of the bus duct through tight hollowing. The surface of the busbar trunking shell is galvanized and sprayed with fireproof coating (when exposed to fire, the coating can quickly expand at a geometric speed on the surface of the busbar, forming a dense carbonized insulation layer, sealing all gaps in the busbar shell, and preventing high temperatures from directly entering the inside of the busbar).

The ambient temperature is -5 ℃/+40 ℃, and the average temperature within 24 hours is not greater than 35 ℃.

The relative humidity of the air should not exceed 50% at+40 ℃ and 90% at+20 ℃.

The altitude shall not exceed 2000m.

The pollution level shall be selected as level 3 according to the provisions of GB7251.1-1997 "Low voltage switchgear and control equipment - Part 1".

3. The joint adopts fire-resistant insulation components, which are reliable and convenient to connect.

Reduce the short-circuit electromotive force between phases because the dual shielding effect of eddy currents and circulating currents on the shell greatly reduces the short-circuit electromotive force acting on the phase conductors

How to use fire-resistant busbars and fire-resistant cables reasonably? As fire-resistant cables or fire-resistant busbars are not only used as emergency power lines in case of power grid or line problems, but also as transmission lines in case of fire or other disasters, fire-resistant busbars must be able to ensure normal power transmission at high temperatures. When the ambient temperature reaches 700 ℃ or above, they can also ensure power supply operation for more than 1.5 hours without causing internal insulation reduction and short circuit between lines due to the increase in ambient temperature. When the transmission current of the line is not very high and the space for laying cables is limited with many bends, using fire-resistant cables is more suitable. However, when the transmission current of the line is relatively high, multiple fire-resistant cables are needed, which is inconvenient for construction and future operation and maintenance. When the capacity of the transmission line is large, fire-resistant busbars are generally used

Mainly focus on the density, the more compact the better. Bus duct and bus duct connectionThe IP protection level of the connector: The protection level refers to the process technology, and the connector is a part of the busbar engineering with a high accident rate. The connector has a high number of short-circuit accidents caused by heating, moisture, or water ingress, especially the IP protection level of the connector should be paid attention to. Because GB7251.2-2006 is a direct translation of the standard IEC60439.2-2000, the protection level test in this standard does not mention that the joint between busbars should undergo a protection level test. The 3C certification currently being implemented in China has formulated implementation rules based on this standard, so it depends on the sealing condition of the joint between the sample busbars. Review of fire resistance test report: mainly reviewing the fire resistance performance of the fire-resistant bus duct. Because fire-resistant bus ducts not only have various technical parameters and tests of ordinary bus ducts, but also require the integrity of the power supply line to be maintained when the bus duct catches fire. It is necessary to maintain the normal power supply of main lines such as fire equipment, emergency lighting, backup lighting, and generator power supply. Therefore, the overall grounding technology using the shell as the PE row is effective in anti-corrosion performance. The aluminum profile shell has much better anti-corrosion performance after anodizing for 10u and galvanizing Long term atmospheric exposure tests on different grades of aluminum alloy sheets and galvanized copper sheets in Japan have shown that the corrosion depth of the former is approximately one twentieth that of the latter, compared to steel shells. A reliable insulation method is that there is an insulation layer on the conductive busbar, and there is a certain air gap between the phases. There is also an insulation pad made of DMC material pressed between the conductive busbar and the shell, with triple insulation to ensure the insulation of the bus duct, especially when used in humid environments. The length of large-span design linear bus ducts is not limited by transportation capacity, and their design and production capacity are not limited by length, which can meet the needs of engineering, especially modern factories, for large-span bus ducts. Due to its good rigidity, there is no need to install hangers between 6m spans. Easy to install due to consistent overall dimensions and symmetrical internal structure. It can be arranged on either side, making it easy to invert and easy to install.

Terms of Use

The ambient temperature is -5 ℃/+40 ℃, and the average temperature within 24 hours is not greater than 35 ℃.

The relative humidity of the air should not exceed 50% at+40 ℃ and 90% at+20 ℃.

The altitude shall not exceed 2000m.

The pollution level shall be selected as level 3 according to the provisions of GB7251.1-1997 "Low voltage switchgear and control equipment - Part 1".

In the selection of busbars, there should be the fire resistance time and standards of refractory materials, and of course, the choice of relative durability is good.

Having the same "sandwich" phase line tightly stacked structure design as the "CMC series", the bus duct has a compact appearance and small volume. The bus system has the advantages of low impedance, voltage reduction, and good dynamic and thermal stability, without the possibility of "chimney effect" formation in case of fire.

The shell is composed of a mixture of cold drawn thin steel profiles. The two side panels are our company's double-layer hollow structure. Effectively preventing high-temperature gases or open flames from directly entering the interior of the busbar through a sealed hollow structure. The surface of the busbar shell is galvanized and sprayed with fireproof coating (when exposed to fire, the coating can quickly expand at a geometric speed on the surface of the busbar to form a dense carbonized insulation layer. Seal all gaps in the busbar shell to prevent high temperatures from directly entering the interior of the busbar).

NHMC-550A fire-resistant bus duct

use

1. It is necessary to verify that the phase sequence of the busbar trunking is correct, and the insulation resistance of the busbar trunking is not less than 20M Ω2. Ensure that the busbar trunking is not invaded by liquids or solids3. It is necessary to confirm that the installation bracket is stable and the connecting bolts are reliably connected4. Contact with live equipment components is dangerous!5. When the bus duct starts to transmit power, it must not carry a load6. Check that the total load current does not exceed the main bus current or design currentBus duct connectors refer to differential circuits composed of all branch currents except for bus tie switches and section switches. The small difference of a certain section of busbar refers to the differential circuit composed of all the branches connected to the busbar, including the busbar and section switches, and the current. The large difference ratio differential of the busbar is used to distinguish between defects inside and outside the busbar area, while the small difference ratio differential is used for selecting defective busbars.

parameter
1. Working voltage: AC380V ± 10% 50Hz; Power consumption: 5KW
2. Furnace pressure measurement range: 0-100Pa Measurement accuracy:
3. Air flow rate: 0-50m3/min Measurement accuracy: ≤± 0.5 m3/min
4. Combustion gas source: propane, liquefied gas
5. Gas tank capacity: 50kg × 4
6. Test temperature: Program heating for 60 minutes, room temperature -925 ℃, 120 minutes
7. Room temperature -1050 ℃ 180min Room temperature -1115 ℃ 240min
8. Room temperature -1150 ℃
9. Furnace temperature: ± 15 ℃
10. Internal temperature of the specimen: ± 10 ℃
11. Test piece backfire temperature: ± 4 ℃
12. Temperature sensor:
13. Furnace: 6 armored nickel chromium nickel silicon K-value thermocouples Grade: II
14. Back fire: 6 armored nickel chromium nickel silicon K-value thermocouples Grade: Grade II
15. Timing range: 0-360min

16. Horizontal burning length of sample: 2.4m
Flame retardant testing machine for power cable busbar trunking, sample vertical * large combustion length: 1.6m
Equipment dimensions: length x width x height (3 x 2 x 2.5) m;
Equipment weight: approximately 4000 Kg, installed on site.