Results 1 to 8 of 8

Thread: The cable between a machine and the wall mounted isolator

  1. #1
    Platinum Member
    Join Date
    Mar 2022
    Location
    South Africa
    Posts
    2,274
    Thanks
    60
    Thanked 103 Times in 98 Posts

    The cable between a machine and the wall mounted isolator

    Something I have never really bothered about, if the machine is supplied with a the cable attached.

    Lets say I install a 32 triple pole isolator on the wall, connected to a 32 amp D curve breaker in the main DB, fed from a 4 mm 4 core+E surfix 30 metres away.

    The machine arrives and it has a 1.5mmx 5 core cabtyre hanging out the machine for connection to the isolator.

    Can you connect the cabtyre directly to the isolator ?

  2. #2
    Gold Member
    Join Date
    Jun 2020
    Location
    Fourways
    Posts
    777
    Thanks
    121
    Thanked 36 Times in 35 Posts
    Interesting, i would say yes, you designed the cable suitable protection. What ever the appliance has is non of our concern as we only test to isolator for fixed appliance in that case.

    However if the manual tells us what size CB to have then I would follow that as manufacturers instructions.

    Still interested as we test to connection points or terminations so then is that the appliance chocolate block or the isolator?? I say isolator as that machine can be changed whenever but the installation wiring is correct.

    Sent from my CPH2197 using Tapatalk

  3. #3
    Platinum Member Derlyn's Avatar
    Join Date
    Mar 2019
    Location
    East london
    Posts
    1,708
    Thanks
    127
    Thanked 160 Times in 150 Posts
    That piece of 1,5mm lead is part of the installation, much the same as a stove.

    One cannot have a 32A breaker protecting a 1,5mm cable. Max is 16A, therefore there are 2 options. Depending on the rating of the machine, either upgrade the lead or downgrade the circuit breaker accordingly.

  4. #4
    Platinum Member Derlyn's Avatar
    Join Date
    Mar 2019
    Location
    East london
    Posts
    1,708
    Thanks
    127
    Thanked 160 Times in 150 Posts
    @Dylboy.

    I must disagree with your statement about only testing to isolator for fixed appliances. The code includes the wiring up to the connection terminals on the appliance.

    As soon as there is an isolator involved, then the wiring between the isolator and appliance is part of the installation.
    This is,however, not the case with a socket outlet.

  5. #5
    Gold Member
    Join Date
    Jun 2020
    Location
    Fourways
    Posts
    777
    Thanks
    121
    Thanked 36 Times in 35 Posts
    I do agree as well but when the cable is on the appliance then I sometimes wonder as then I need to open the back plate of the oven for example and potential to void a Smeg warranty haha

    Sent from my CPH2197 using Tapatalk

  6. #6
    Gold Member
    Join Date
    Jun 2020
    Location
    Fourways
    Posts
    777
    Thanks
    121
    Thanked 36 Times in 35 Posts
    But end of the day the CB must cover that lead anyway.

    Sent from my CPH2197 using Tapatalk

  7. #7
    Junior Member
    Join Date
    Oct 2018
    Location
    Gauteng
    Posts
    20
    Thanks
    2
    Thanked 2 Times in 2 Posts
    Quote Originally Posted by Derlyn View Post
    That piece of 1,5mm lead is part of the installation, much the same as a stove.

    One cannot have a 32A breaker protecting a 1,5mm cable. Max is 16A, therefore there are 2 options. Depending on the rating of the machine, either upgrade the lead or downgrade the circuit breaker accordingly.
    I agree. Unfortunately will have to provide adequate protection for the 1.5mm cable. Being only 1,5mm the appliance does not need more than 16A ... so easiest is to just put 16A c/b in db.

  8. #8
    Platinum Member
    Join Date
    Mar 2022
    Location
    South Africa
    Posts
    2,274
    Thanks
    60
    Thanked 103 Times in 98 Posts
    If we do an installation were we install a cable and isolator, generally we would be connecting the machine or fixed appliance, so the whole circuit from the DB to the appliance terminals will be done by us, however I have noticed in may cases the person who installed the isolator is not the same person who connects the appliance to the isolator.

    Another example would be were an installation is completed, the company disconnects all the machine sand moves, a new company moves in a uses the isolators supplied.

    I would assume the person who connects all new machines would have to supply a supplementary COC for the connection from the isolator to the machine/appliance?

    The same with a geyser, if a plumbers replaces the geyser and replaces the wiring between the isolator and the new geyser. IF the wire from the DB to the isolator is 4 mm fed from a 30 amp mcb, you cant just replace the geyser and the wire from the isolator with a 2.5 mm FTE. The breaker would need to be replaced with a 20 amp mcb.

Similar Threads

  1. LED Ceiling mounted lights surge protection
    By Thys LOW Elektries in forum Electrical Contracting Industry Forum
    Replies: 3
    Last Post: 01-Aug-21, 02:00 PM
  2. 2 x 10mm in Isolator.
    By skatingsparks in forum Electrical Contracting Industry Forum
    Replies: 11
    Last Post: 27-Oct-20, 09:06 PM
  3. Hob Isolator
    By chriskrn1 in forum Electrical Contracting Industry Forum
    Replies: 5
    Last Post: 22-Aug-16, 12:14 PM
  4. [Article] Exe cable glands for braided cable
    By Master Electrician in forum Electrical Contracting Industry Forum
    Replies: 0
    Last Post: 26-Aug-10, 02:47 PM
  5. VIA announces ultra-thin Vesa mounted PC
    By August in forum Technology Forum
    Replies: 0
    Last Post: 12-Oct-07, 11:25 AM

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
  •