Service Gear Mounting

[Fulthrotl]

It costs too much and it is too difficult to install rails, but there is lots of time and money to shim and force the equipment into some kind of 'tolerable' alignment.

You should not need a pry bar to get a door to open or close.
Yes some of it is marginal manufacturing, but a lot of it is equipment not being level and true.

i'm currently getting a housekeeping pad ready to pour for switchgear, and was thinking about this....
i have the luxury of not having to pour the pad until the gear is on site, and i can verify actual measurements
of conduit windows, etc.

i was thinking of strut embedments for the anchor bolts. this being california, there is a seismic kit to put on
as well, but i'm thinking the short strut embedments like the sprinkies use for hangers, the serrated stuff
with ears on the side of the strut to lock it in. put two 20' ribbons the length of the pad, and drill and anchor
HV gear, 225kva xfmr, and LV gear with the whole thing....

as far as level goes, that form will be within 1/16", so as long as the concrete is floated well, it should be
flat. the strut embedments will be rail straight and level, so if they are proud a bit of the surface, all should
end up straight.....

 

[infinity]

If I am paying for breakers that rack, then I will gladly pay for channels in the pad.

I agree, another contractor installed several sections of switchgear on uneven pads and the breaker racking was a problem. When it came time for some additional gear the engineers spec'd steel rails in the pad to ensure everything was square and level and the problem never became an issue in the new gear.

 

[mstrlucky74]

I agree, another contractor installed several sections of switchgear on uneven pads and the breaker racking was a problem. When it came time for some additional gear the engineers spec'd steel rails in the pad to ensure everything was square and level and the problem never became an issue in the new gear.

How would the breaker racking be a problem.Trying to rack them in or once they are in it's a problem?

Also with the rail embedded in the concrete. Once the gear is placed on the rails how is it attached securely to the rails?

 

[mstrlucky74]

Yes, I have done that several occasions. One where the existing gear had problems with racking style breakers due to the pad being so uneven. Here's a recent one for a 25000 pound generator where the steel was set with a laser and mounted on strut:

So from what I can see the rebar is mounted on the strut and the bolts coming out of the strut attach to the equipment? Thanks.

 

[mstrlucky74]

Guys isn't it the concrete guys responsibility to make sure the pad is level? That should not be hard for him.

 

[infinity]

How would the breaker racking be a problem.Trying to rack them in or once they are in it's a problem?

Also with the rail embedded in the concrete. Once the gear is placed on the rails how is it attached securely to the rails?

Are you familiar with large racking circuit breakers that ride on a rail system to allow them to be installed and removed? If the gear is twisted due to a crooked pad racking can be a big problem. Depending on the weight of the gear gravity may hold it in place or some sort of bolting on the inside of the gear.

So from what I can see the rebar is mounted on the strut and the bolts coming out of the strut attach to the equipment? Thanks.

The rebar and strut are below the surface of the concrete. The rods sticking up through the steel rails are cut off or removed after the pour. In this installation large springs were welded to the rails that the generator sat on.

Guys isn't it the concrete guys responsibility to make sure the pad is level? That should not be hard for him.

It must be hard because they're usually not level. :roll:

 

[mstrlucky74]

Are you familiar with large racking circuit breakers that ride on a rail system to allow them to be installed and removed? If the gear is twisted due to a crooked pad racking can be a big problem. Depending on the weight of the gear gravity may hold it in place or some sort of bolting on the inside of the gear.



The rebar and strut are below the surface of the concrete. The rods sticking up through the steel rails are cut off or removed after the pour. In this installation large springs were welded to the rails that the generator sat on.



It must be hard because they're usually not level. :roll:

Thanks!!!

 

[plumb bob]

Guys isn't it the concrete guys responsibility to make sure the pad is level? That should not be hard for him.

:lol: :lol: thanks, I needed a laugh after the day I had today

 

[mstrlucky74]

:lol: :lol: thanks, I needed a laugh after the day I had today

Glad I could help.