Circuit Breaker HP rating Question

[gappvembe]

Hi,
My boss has come up with a question I don't have an answer to. We are using Allen-Bradley Circuit Breakers (Cat. 1492-CB3 G200). The thing that bothers him is that while the Breakers are rated at 20A, they have labeled after them 10HP.
Below that in even smaller print they have listed "AC 480Y/277V 3ph". Any way you slice it, 20 Amps do not protect a 10 HP, except for the one rated at 460 Volts per Table 430.250. Then again it's not an even 20 Amps, but 14 Amps.

http://literature.rockwellautomation.com/idc/groups/literature/documents/ca/a115-ca905_-en-d.pdf

 

[zog]

That breaker is rated for 600V max the HP rating is based on the 600V rating.

 

[jim dungar]

Hi,
My boss has come up with a question I don't have an answer to. We are using Allen-Bradley Circuit Breakers (Cat. 1492-CB3 G200). The thing that bothers him is that while the Breakers are rated at 20A, they have labeled after them 10HP.
Below that in even smaller print they have listed "AC 480Y/277V 3ph". Any way you slice it, 20 Amps do not protect a 10 HP, except for the one rated at 460 Volts per Table 430.250. Then again it's not an even 20 Amps, but 14 Amps.

http://literature.rockwellautomation.com/idc/groups/literature/documents/ca/a115-ca905_-en-d.pdf

It means, the breakers are rated to act as switches and short circuit protection for 10HP not necessarily running overcurrent protection.