| Arc Flash Forum https://brainfiller.com/arcflashforum/ |
|
| Mcc cat https://brainfiller.com/arcflashforum/viewtopic.php?f=2&t=1675 |
Page 1 of 1 |
| Author: | toolbbin [ Sun Apr 17, 2011 6:02 am ] |
| Post subject: | Mcc cat |
If the main switchgear is lets say a 4 and their feeding breakers to a mcc are 4 will this automatically make the main cb in the mcc be a 4 also ? 480 volt SG 480volt mcc |
|
| Author: | George [ Sun Apr 17, 2011 7:13 pm ] |
| Post subject: | |
The impedance of the cable between the switchgear feeder breaker and the MCC could change things. It might reduce the arcing current enough to lower the calculated incident energy, or it might reduce the arcing current enough to move the trip time of the protective device out of the instantaneous range and thereby increase the incident energy. The incident energy at the MCC should be calculated. |
|
| Page 1 of 1 | All times are UTC - 7 hours |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|