Disconnect Switch Replacement

[powereng1]

This is my first time working on a disconnect switch replacement project for a local client. The high of the existing disconnect is 21 FT and that is from the top of its foundation to the center line of the disconnect 4-hole pad (as well as the center line of the bus). The new switch is 0.125 inches higher so I am unsure how to transition from the bus which is at 21 FT to the disconnected terminal which is .125 higher. Can anybody suggest any ideas?

Thanks in advanced.

 

[DRWeig]

Can you tell us voltage, amps, bus dimensions?

Best to you,

Goober Dave

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[powereng1]

The voltage level is 345KV, 3000A, bus 5", bus high 21FT. Thanks

 

[waross]

Drill all connecting holes out another 0.0625 inches. There may already be enough clearance in the bolt holes to bolt up without extra drilling.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[jghrist]

I don't think that the centerline of the old disconnect terminal would be at the same height as the centerline of the bus. If the bus terminal connector is center-formed and placed on top of the switch pad, the bottom side of the bus terminal (center of bus) would be at the same height as the top of the switch pad, not the center of the pad. If it was placed on the bottom of the switch pad, the top side of the bus terminal (center of bus) would be at the same height as the bottom of the switch pad. If the bus terminal were not center-formed, the center of the bus would be offset from the switch terminal pad.

In any case, unless the connecting bus is very short, it wouldn't have to bend much to make up for 1/8" of height difference.

I'm assuming a horizontally mounted switch and horizontal bus. Waross must be considering vertical mounting.

 

[collies99]

We use flex linjs from ips to switch. Have you made a field inspection ?

 

[collies99]

If it is horizontal mount, rotsing column and fixed column all have leveling bolts, and should be movable up or down by the amount stated. Please see instalation manual ninimum / maximum height. Your maybe the median if taken of a spec sheet.