4.7.1 Does a remote contactor with a local control switch meet the requirements?

[JamieP]

"shall be provided with a switch, operating in all active conductors, mounted near the appliance in a visible and readily accessible position."

Reading this the switch that is mounted near the appliance in a visible and readily accessable position must operate in all active conductors but a local control switch doesn't actually do this, it opperates in a control circuit

What are peoples thoughts? I frequently see or hear of the contactor arrangement but have always questioned it's compliance

[PeteRig]

Doesn't meet the requirements of 3000:2007 2.3.2.2 I believe

[JamieP]

Neither arrangement does

But neither arrangement has too because a device for isolation is not required. Only a switch.

Unless you're referring to the contactor at the switchboard? That will still have a protective device upstream of it.

[JamieP]

Oh what a dick I am, sorry, meant to quote 4.7.1, will fix this, sorry!

[AlecK]

Correct; the switch required by 4.7.1 is not an isolating switch, so 2.3.2.2 is not applicable.

True the wording suggests that the switching has to be "visible" and "readily accessible";
But very pedantic to argue that this prohibits using a remote contactor together with a visible / accessible operating switch.


The key factors are
- does the switching device operate in all active conductors?; and
- is the means of operation readily accessible?


The purpose is simply to provide a quick and easy means of removing the source of heat in case of fire;
(without having to reach across a burning frypan, as per Note 1).

So in my view, if the arrangement fulfills the purpose and meets the specified parameters, it's acceptable.

[JamieP]

More directed that it seemed to want the switch to switch all actives locally, not to switch all actives remotely

But what you say makes sense, appreciated

[AlecK]

Agree that inference can be taken from the wording.
But certainly not clearly stated, and remote operation not clearly prohibited.

[AlecK]

Further, Note 2 explains that a common switch can be used for several appliance in same room.
(In 2018 edition, this is upgraded from Note to paragraph of clause)

This might stretch the 2m guideline.
But given that open cooking surfaces tend to be high-power appliances, and therefore unlikely to be on same circuit;
it suggests that the means of operating the switching device can be remote from the device.

Also; the term "switch" is defined by IEC as:
" device for changing the electric connections among its terminals "
so includes a relay / contactor.
And for any such device; the operating function is necessarily separate from the switching device