Code letter on motor name plate

[No hacks allowed]

In sizing a motr diconnect. What doees the code letter on the motor mean? I know that you dont just size the disconnect according to the R.L.A. Please embelish.

 

[guschash]

Look at table 430.7(B)

 

[FrancisDoody]

Disconnect

Disconnect

There are two ways to figure the motor disconnect. The first being Horsepower and the second being those described in 430.109 (B).

The motor diconnect must be horsepower rated and capable of deenergizing the LRC of table 430.251.

The disconnect must be sized to 115% of the full load current (FLA) in order to handle the in-rush current per 430.110.

The code letter is required by the NEC and designates the highest horsepower with the rotor-locked. Generally you would only use this in special circumstances.

 

[jim dungar]

The code letter is used to look up a multiplier which is then used to determine the amount or locked rotor kVA per horsepower.

 

[No hacks allowed]

Yes but why are there two sets of #s, which size do you use?

 

[augie47]

Code Letter

Code Letter

Yes but why are there two sets of #s, which size do you use?

If you are refering to 430.151(B) {two sets of numbers}, one is for design E motors. The higher in-rush on design E motors is one of the reasons, I believe, you seldom see them.

 

[don_resqcapt19]

The higher in-rush on design E motors is one of the reasons, I believe, you seldom see them.

You never see them because they never were any manufactured.
Don

 

[augie47]

e motors

e motors

my error. I thought they were around , but scarce.
even foreign equipmet ??