The minimum span when the commonly used rectangular busbars are arranged relative to the thickness direction of the busbars

The minimum span when the commonly used rectangular busbars are arranged relative to the thickness direction of the busbars

 

  For example: for a 31 copper busbar bending machine.5kA system, ich takes 80kA, such as for KYN28-12 switchgear a=27.5cm, for TMY100×10 and LMY100×10

Then: L copper MAX≤755 (mm).

L aluminum MAX≤530 (mm).

It can be seen from the calculation that for the 31.5KA system, if the relative arrangement of the 100×10 bus width direction is adopted, if other factors are ignored in the theoretical calculation, the bus support must be controlled within 755mm (530mm), which is 800mm for the cabinet width Switchgear is unrealistic in terms of application. Therefore, this method is generally seldom used in 12KV and 40.5KV switchgear and control equipment, but in low-voltage equipment for structural considerations and to reduce occupied space, it is often used in the side entry line and tie line.

According to the above formula, for several common data, such as the distance between the busbars 210mm, 275mm (12KV voltage grade products) 350mm, 400mm, 460mm (40.5KV voltage grade products), the table is summarized as follows:

The minimum span (mm) when commonly used rectangular busbars are arranged relative to the thickness direction of the busbars:

Short circuit capacity kA/4s 31.5 40

Distance (mm) 210 250 275 350 460 210 250 275 350 460

TMY

100×10 Theoretical value 2100 2280 2400 2700 3100 1680 1830 1900 2160 2475

Recommended value 1800 1800 1800 2200 2200 1400 1400 1400 1800 1800

TMY

80×10 theoretical value 1680 1830 1900 2160 2475 1340 1460 1530 1725 1980

Recommended value 1400 1400 1600 1800 1800 1200 1200 1200 1400 1400

TMY

80×8 theoretical value 1500 1630 1710 1930 2210 1195 1300 1370 1540 1770

Recommended value 1200 1200 1400 1400 1800 1000 1000 1000 1200 1400

TMY

60×6 theoretical value 970 1060 1110 1255 1440

Recommended value 800 800 800 1000 1000

LMY

100×10 theoretical value 1475 1610 1690 1900 2185 1180 1290 1350 1525 1750

Recommended value 1200 1200 1200 1400 1600 1000 1000 1000 1200 1400

LMY

80×10 theoretical value 1180 1290 1350 1525 1750 945 1030 1080 1215 1395

Recommended value 1000 1000 1000 1200 1400 800 800 800 1000 1000

LMY

80×8 theoretical value 1050 1150 1205 1360 1560 845 925 970 1100 1250

Recommended value 800 800 1000 1000 1200 800 800 800 800 1000

    (Table 2)

The minimum span (mm) when commonly used rectangular bus bars are arranged relative to each other in the width direction of the bus bar:

Short-circuit capacity KA/4S 31.5 40

Distance (mm) 275 400 460 275 400 460

TMY

100×10 theoretical value 755 910 980 605 730 780

Recommended value 600 800 800 600 600 600