Installing a Raising Main

KR Busway Trunking Support

The trunking supports fix sections of a vertical run to the building structure. This type of fixing support has the following advantages:

Assembly:
- to a wall,
- to a wall bracket,
- to the floor.
Height and depth adjustment;
Spring adjustment to ensure distribution of the load at each floor;
Avoids the transmission of building forces to the busbar trunking (expansion and vibration).

Installation Principles

While installing KR rising mains, specific supports mentioned in the table below can be used along with expansion unit in vertical raising mains. There is no height limitation for rising mains with KR cast resin busway, but the following guidelines for the design of support system must be followed.

Height of busway	Support type
	Fixed	Springs	Guides
	ZA7 / ZA8 (every 1.5 m)	ZA5 / ZA6 (every 3 m)	ZA9 (between ZA5 / ZA6)	Expansion unit (every 25 m)
0 m to 6 m	✔	–	–	–
6 m to 12 m	✔ Only 2 at bottom	✔	✔	–
12 m to maximum	✔ 2 at bottom and after every 25 m	✔	✔	✔

General guidelines:

In any riser, two fixed supports type ZA7/ZA8 are required at the bottom of a riser.
In any riser, a support is required every 1.5 meters. It can be fixed supports, just guides or guides with springs.

NOTE: In special cases, the maximum of 2 meters distance is accepted between the supports locally but need to adjust on other places to keep an average of 1.5 meters.
For small risers up to 6 meters, only fixed support ZA7/ZA8 is required.
For medium risers beyond 6 meters, spring supports ZA5/ZA6 is required with a distance of 3 meters, and guiding supports ZA9 is required in between two spring supports.

NOTE: For risers 6 to 12 meters maximum, only 1 section (at the bottom) must be equipped with 2 fixed supports and other sections must be extended freely across the guides and spring supports.
For large risers higher than 12 meters, previous guidelines must be followed and in the middle of each 25 meters sections, install an expansion unit to compensate the extension, and install 2 units of ZA7/ZA8 after every 25 meters.