A
I am trying to gather as much information on this topic as i can. I have talked to my engineering peers, electrical inspectors and anyone else i can get relevant information from.
The question i am trying to answer is what options are available for installing (legally) a industrial control or automation system with a low SCCR.
As an example, a new piece of equipment is purchased and it comes with a max 5 KA SCCR label at the incoming power circuit breaker. The utility service is 2.5MVA 480VAC. After factoring in conductor length the available fault current at the point of interconnect is still 20 KA. What options does a owner or client have to deal with the situation. This is the options i have come up with so far
1) have the manufacturer revaluate the equipment or replace components in an attempt to get a higher system SCCR.
2) add additional supply cable length (although we could be talking about a lot of cable in some situations)
3) Install a properly sized isolation transformer
(although depending on the system power requirements it may not be possible to meet the power demands of the system and stay under 5KA SCCR).
This is the options i have come up with so far. I have had some people suggest current limiting fuses can be installed between the system and the utility to lower the available SCCR (using peak let through charts from the fuse vendor). And others have advised me that this is not an acceptable practice.
And i am referring to a system that would be installed in either Canada/US
I would appreciate any comments or feedback
The question i am trying to answer is what options are available for installing (legally) a industrial control or automation system with a low SCCR.
As an example, a new piece of equipment is purchased and it comes with a max 5 KA SCCR label at the incoming power circuit breaker. The utility service is 2.5MVA 480VAC. After factoring in conductor length the available fault current at the point of interconnect is still 20 KA. What options does a owner or client have to deal with the situation. This is the options i have come up with so far
1) have the manufacturer revaluate the equipment or replace components in an attempt to get a higher system SCCR.
2) add additional supply cable length (although we could be talking about a lot of cable in some situations)
3) Install a properly sized isolation transformer
(although depending on the system power requirements it may not be possible to meet the power demands of the system and stay under 5KA SCCR).
This is the options i have come up with so far. I have had some people suggest current limiting fuses can be installed between the system and the utility to lower the available SCCR (using peak let through charts from the fuse vendor). And others have advised me that this is not an acceptable practice.
And i am referring to a system that would be installed in either Canada/US
I would appreciate any comments or feedback
