1/4hp motor

Status
Not open for further replies.

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
430.52 (C) (1) Exception No. 2 would likely permit it.
The manufacturers installation instructions may specify a 15 Amp branch circuit, I have run into this with Bathroom vent fans and installing them on a 20A Bathroom circuit.
Overload relay elements for very small full load motor currents could in theory have such a high resistance that a bolted fault
at the controller load terminals produces a short-circuit current of less than 20 amperes, regardless of the available current at the line terminals. So then in 110.10 would come into play.
 

hhsting

Senior Member
Location
Glen bunie, md, us
Occupation
Junior plan reviewer
430.52 (C) (1) Exception No. 2 would likely permit it.
The manufacturers installation instructions may specify a 15 Amp branch circuit, I have run into this with Bathroom vent fans and installing them on a 20A Bathroom circuit.
Overload relay elements for very small full load motor currents could in theory have such a high resistance that a bolted fault
at the controller load terminals produces a short-circuit current of less than 20 amperes, regardless of the available current at the line terminals. So then in 110.10 would come into play.

Interesting 430.52 exception no. 2 gives power to designer. What would be starting current of 1/4 HP 120V exhaust fan used in lab for kitchen hood?
 
Status
Not open for further replies.
Top