• We will be performing upgrades on the forums and server over the weekend. The forums may be unavailable multiple times for up to an hour each. Thank you for your patience and understanding as we work to make the forums even better.

SCCR for Panel/System

J

Jsantangelo

Member
Location
Columbus,Ohio
Occupation
Electrical Design Engineer
In doing an SCCR calculation can you do the calculation for a panel or panels only? Do I need to do a SCCR calculation for the complete system including devices outside of my panel(s) (i.e. robot controllers, receptacles, etc.)

Thank you for any help.
 
petersonra

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
Jsantangelo said:
In doing an SCCR calculation can you do the calculation for a panel or panels only? Do I need to do a SCCR calculation for the complete system including devices outside of my panel(s) (i.e. robot controllers, receptacles, etc.)

Thank you for any help.
Click to expand...
The only "approved" sccr calculation method for control panels is found in UL508a and only applies to UL508a panels. You have to follow all the rules in the standard.

One of the rules of the standard says that it "does not include an evaluation of the controlled equipment".

To determine if the downstream devices such as a robot controller have an adequate sccr, you have to calculate the available short circuit current at the terminals to that device and make sure it is less than the sccr of that device
 
You must log in or register to reply here.
Top