90 amp compressor question

[Stevenfyeager]

At a tire store, the salesman is telling me that the new compressor needs a 90 amp breaker. The stores only three phase 208 Delta panel is 100 amps only. It’s packed with balancing machines , car lifts and two older compressors.
My amp meter reads not more than 30 A on each of the three legs but the two existing compressors were not kicking on for me at that time. His specs say wire size number six with 48 FLA. specs says circuit breaker size 90 amp industrial breaker. It also requires a fusible switch heavy duty with dual element time delay fuse of 60 A.
I’ve never wired for this heavy duty compressor before. Any advice would be greatly appreciated. Thank you.

 

[norcal]

No such thing as 208 delta.

 

[Johnhall30]

The only code compliant way to ensure this service is sized appropriately is do a 30-day load study and find the maximum demand, and use 125% of that.

Add your new compressor FLA (48 Amps)

Determine if the compressor will be a continuous load (125% of 48 Amps if so)

If you are under 100 Amps then the service is ok

 

[roger]

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