Isolators for Fixed Appliances

[BlueArc]

Need help!

Does an Air conditioner require an isolator if it does not exceed 16A.

Below is an extract from SANS 10142.1 Edition 1.8
6.16.4.1.1 Dedicated circuits shall be provided for fixed space heating and
cooling (air-conditioning units) that are rated at more than 16 A. There may
be more than one unit on each circuit and the power supply to each unit shall
be controlled by a switch-disconnector

I'm having trouble explaining this to an electrician as he says since the AC unit is below 16A it does not require an isolator next to the unit.

[RegElec]

If the unit is permanently wired ie not plugged in then it is a fixed appliance and does require a double pole isolator. The supply can be taken from a plug circuit if it is less than 16A. However if it is over 16A a dedicated air conditioner circuit must be provided for the supply to the air conditioner but that will still need an isolator.

[Dave A]

As 6.16.4.1.1 is entirely silent on space heating and cooling appliances that are rated at less than or equal to 16A, the clause is largely irrelevant when it comes to determining the isolator requirements for such appliances. It is also worth mentioning that the primary point introduced by the clause is the provision of dedicated circuits - the consequences on the arrangement of isolators is effectively secondary.

The hurdles to overcome generally when it comes to isolators for fixed appliances lie in 6.16.1.

6.16.1.3 The power supply to every fixed appliance, except luminaires, shall be supplied through

a) a disconnecting device that disconnects both live conductors in a single-phase supply and all phase conductors in a multiphase supply, or

b) a socket-outlet

that is directly accessible...

6.16.1.5 The disconnecting device shall be positioned

a) within 1.5 m from the appliance, or

b) in a distribution board (if the switch-disconnector is capable of being locked in the open position).

Even where a ...

Perhaps your electrician needs to explain how his proposed arrangement complies with these two foundation sections.