Page 3 of 3 FirstFirst 123
Results 21 to 28 of 28

Thread: Do circuit breakers need to be SABS APPROVED

  1. #21
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,923
    Thanks
    576
    Thanked 934 Times in 755 Posts
    I think you can take it that they're the genuine item then and they're not necessarily displaying their SABS compliance on the actual product although I couldn't for the life of me begin to guess why not.

    Their concerns around the lack of main circuit breaker were similar to mine although it is plausible the Eskom protection could fulfill the requirements under certain circumstances. I think the problem with relying on the Eskom MCB for DB overload protection is that there's nothing to stop it being replaced or even being removed by Eskom at any given time if there was alterations to their network for example.
    _______________________________________________

    _______________________________________________

  2. #22
    Full Member MullerR's Avatar
    Join Date
    Jan 2016
    Location
    Lady Grey
    Posts
    44
    Thanks
    3
    Thanked 6 Times in 5 Posts
    Their concerns around the lack of main circuit breaker were similar to mine although it is plausible the Eskom protection could fulfill the requirements under certain circumstances. I think the problem with relying on the Eskom MCB for DB overload protection is that there's nothing to stop it being replaced or even being removed by Eskom at any given time if there was alterations to their network for example.
    6.8.1 Circuit-breakers used as main or local switch-disconnectors

    A circuit-breaker that is used as a main or local switch-disconnector (see
    6.9.4) shall comply with the relevant requirements of a standard given in
    clause 4 for switch-disconnectors, or, alternatively, a switch-disconnector
    shall be positioned on the supply side of the circuit-breaker
    .
    Please correct me if I interpret it wrong. According to 6.9.4 if you use a circuit breaker as a switch disconnector, it must comply with clause 4 for switch disconnectors, BUT if not, a switch disconnector shall be positioned on the Supply side of the Circuit breaker, thus meaning it shall be installed on the incoming side of the circuit breaker. (Supply side = Incoming, Load Side = Outgoing). So the arrangement will be Switch Disconnector, Main Circuit Breaker and then the rest of the circuit breakers for the installation? So my confusion is why is it allowed in certain areas that the upstream supply breaker can be used as the circuit breaker for OC faults if 6.9.4 states the switch disconnector must be installed on the supply side of the circuit breaker? As Bergie Mentioned:
    on a normal db and sub db it is acceptable to have your overload protection upstream,
    , are these two regulations not contravening one another, OR am I interpreting the Supply side of Circuit breaker wrong?

  3. #23
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,923
    Thanks
    576
    Thanked 934 Times in 755 Posts
    Quote Originally Posted by MullerR View Post
    Please correct me if I interpret it wrong. According to 6.9.4 if you use a circuit breaker as a switch disconnector, it must comply with clause 4 for switch disconnectors, BUT if not, a switch disconnector shall be positioned on the Supply side of the Circuit breaker, thus meaning it shall be installed on the incoming side of the circuit breaker. (Supply side = Incoming, Load Side = Outgoing). So the arrangement will be Switch Disconnector, Main Circuit Breaker and then the rest of the circuit breakers for the installation? So my confusion is why is it allowed in certain areas that the upstream supply breaker can be used as the circuit breaker for OC faults if 6.9.4 states the switch disconnector must be installed on the supply side of the circuit breaker? As Bergie Mentioned: , are these two regulations not contravening one another, OR am I interpreting the Supply side of Circuit breaker wrong?
    From my understanding the switch disconnector would only be required to be upstream of the main OCPD if both items are within the DB because it's the DB that requires 2-pole disconnection.
    _______________________________________________

    _______________________________________________

  4. #24
    Bronze Member
    Join Date
    Mar 2012
    Location
    Account_Deleted
    Posts
    165
    Thanks
    122
    Thanked 23 Times in 18 Posts
    What is more worrying is that none of the "major" manufacturers can supply authenticated documentation of:

    Please send me the certification for your following CIRCUIT BREAKERS please:
    Circuit-breakers used as switch-disconnectors (isolators) In < 125 A and Icu < 10 kA

    VC 8036a plus 4.8 of SANS 152d,

    or

    VC 8036a plus SANS 60947-2


    (From Clause 4 (SANS 10142) (Circuit breakers used as switch disconnectors)

    Not one has come back with documentation.

    CBI, Schenker or LEAR circuit breakers cannot be used as Switch-Disconnectors then?

    So if their c/breakers are not compliant to be used as switch disconnectors (which are required by regs) does that mean that most installations does not comply? (Where there is ONLY a circuit breaker and no switch disconnector or "6.9.1.1 - disconnecting device"

    MAKE SURE YOU KNOW THE The difference.
    Last edited by ACEsterhuizen; 27-Jul-16 at 05:38 PM. Reason: more info

  5. #25
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,923
    Thanks
    576
    Thanked 934 Times in 755 Posts
    All manufacturers should be able to supply compliance documentation for their circuit breakers or they should state that they're not rated as switch disconnectors. Maybe try communicating with them again a little more assertively by pointing out it's a legal requirement this documentation is supplied on request.

    Something else that struck me as being odd was in Gilberto's previous post he stated;
    Quote Originally Posted by Gilberto Silva View Post
    .......but he did also mention over the phone that their is specific things in the circuit breakers that he would know definitely its CBI parts but couldn't divulge those details to me.........
    So CBI are basically keeping info on how to spot counterfeit items as trade secrets and even when there's a specific suspicion raised they're not telling customers how to spot a fake. How does that work? All the major players in most industries have entire web pages and published fact sheets available on how to spot pirated or fake items yet Gilberto's comment suggests CBI's policy appears to be the exact opposite.

    Here's a few examples of counterfeit info from several companies;
    Clipsal
    Schneider
    Eaton

    I see there's some info here on counterfeit MCB's but I'm not sure if it was officially provided by CBI.
    _______________________________________________

    _______________________________________________

  6. Thanks given for this post:

    Dave A (27-Jul-16)

  7. #26
    Full Member MullerR's Avatar
    Join Date
    Jan 2016
    Location
    Lady Grey
    Posts
    44
    Thanks
    3
    Thanked 6 Times in 5 Posts
    From my understanding the switch disconnector would only be required to be upstream of the main OCPD if both items are within the DB because it's the DB that requires 2-pole disconnection.
    So my understanding is also correct by implying that the double pole isolator should be installed before the circuit breaker.

    Now I have another point. Most circuit breakers have the symbol Click image for larger version. 

Name:	Symbol_Circuit-breaker.jpg 
Views:	432 
Size:	9.0 KB 
ID:	6378 which is not suitable for isolation according to SANS 10142, Table Q1, but the symbol Click image for larger version. 

Name:	MCB Isolation.gif 
Views:	1692 
Size:	2.6 KB 
ID:	6379 according to SANS 10142, Table Q1 suggests it is suitable for Isolation? Does that mean when you install a double pole circuit breaker Click image for larger version. 

Name:	QF-N-2_13_-10A-6kA_grande.jpg 
Views:	454 
Size:	14.0 KB 
ID:	6380 with the symbol suitable for isolation, it is allowed to be used as the switch disconnector?

  8. #27
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,923
    Thanks
    576
    Thanked 934 Times in 755 Posts
    Quote Originally Posted by MullerR View Post
    ........Does that mean when you install a double pole circuit breaker with the symbol suitable for isolation, it is allowed to be used as the switch disconnector?
    As I understand it that symbol means it is capable of being used as a switch disconnect assuming it has sufficient poles for that particular installation. Also the green toggle on a CBI MCB or SP+N denotes it as an isolator or switch disconnector. TBH I haven't seen an MCB in a long time that doesn't qualify as a switch disconnector, from what I remember the device needs to have positive forced disconnection of the internal switch contacts when it trips and also a certain gap between the contacts when they're in the open position. There may be other requirements as well but I think nowadays most of the major MCB suppliers are fulfilling these requirements with their standard OCPD's such as MCB's and SP+N's etc making them dual purpose.
    _______________________________________________

    _______________________________________________

  9. #28
    Bronze Member
    Join Date
    Mar 2012
    Location
    Account_Deleted
    Posts
    165
    Thanks
    122
    Thanked 23 Times in 18 Posts
    Switch symbols: The horizontal line in the switch symbol of the contacts indicates that they fulfill the isolating function.



    Click image for larger version. 

Name:	switch-symbols.gif 
Views:	554 
Size:	5.4 KB 
ID:	6382

Page 3 of 3 FirstFirst 123

Similar Threads

  1. [Question] Installation of circuit breakers
    By Harry S in forum Electrical Contracting Industry Forum
    Replies: 5
    Last Post: 30-Jan-16, 07:12 AM
  2. [Question] Flash Barrier Protection on Circuit Breakers
    By BlueArc in forum Electrical Contracting Industry Forum
    Replies: 4
    Last Post: 16-Sep-15, 11:15 AM
  3. [Question] Circiut Breakers
    By Martinco in forum Electrical Contracting Industry Forum
    Replies: 14
    Last Post: 22-Apr-11, 02:47 PM
  4. sabs approved socket outlet
    By murdock in forum Electrical Contracting Industry Forum
    Replies: 10
    Last Post: 15-Sep-10, 12:52 AM
  5. Circuit breakers
    By adrianh in forum Electrical Contracting Industry Forum
    Replies: 3
    Last Post: 25-May-10, 12:37 AM

Tags for this Thread

Did you like this article? Share it with your favourite social network.

Did you like this article? Share it with your favourite social network.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •