SCCR For Elevator

[jstandefer@e3electric]

Our customer is saying it is our responsibility as the electrical contractor to label our fused 35A 480V disconnect with a SCCR rating per the Elevator inspectors request. He says it is per NEC 110.24. The elevator controller only has a 5k SCCR and our electrical system is 10k. Everything I find is that the controller itself is not code compliant. Has anyone had this issue? How would I lower the SCCR rating of our disconnect?

 

[jim dungar]

How would I lower the SCCR rating of our disconnect?

You cannot change the rating of your disconnect.
What the inspector probably wants to know is how much short circuit amps are available at your disconnect switch. Has this calculation been done?

You maybe able to lower the amount of available fault current at the elevator controller. The easiest way is to add impedance by increasing the length of the feeder conductors or by adding a transformer.

But you should also see if the elevator controller has a series rating with a specific fuse type. This information can only come from the controller manufacturer.

 

[augie47]

They seem to be addressing a basic requirement of electrical installations but their terminology and Code references are not correct, 110.24 address service equipment marking and you can't "change" the SCCR of equipment.
Most likely what they want addressed is the available fault current at the elevator equipment to assure it is not higher than 5k.
If it's a designed job this should have been addressed by the engineer.

(Mr. Dungar answered as I was typing with a better explaination)

 

[don_resqcapt19]

Unless you are on the 2026 code, nothing in 110.24 would require the disconnect to be marked with the available fault current.