CERTIFICATE OF COMPLIANCE SERIES – PART 9
By Cecil Lancaster, ECA(SA) Regional Director, Bosveld region
The ninth in a 13-part series that gets back to the basics …
Certificates of Compliance:
Because of all the questions and the arguments regarding the Certificate of Compliance (CoC) for Electrical Installations, the ECA has prepared this series of articles in which we endeavour to clarify the requirements strictly in terms of the legal requirements.
The documents referred to are:
- The Occupational Health and Safety Act, No 85 of 1993 (OHS Act).
- The Electrical Installation Regulations of 2009 (EIR).
- SANS 10142-1:2017, Edition 2.0:
SOUTH AFRICAN NATIONAL STANDARD
The wiring of premises
Part 1: Low-voltage installations
All these documents are available in the public domain, the first two from our website http://ecasa.co.za at no cost to our members, and the other directly from the SABS or via our offices.
Part 9: The Test Report. Section 4 – Inspection and Tests – Part 2
Item 6: Disconnecting devices
In this part we will continue with the detailed discussion of the INSPECTION aspect of completion of the CoC.
Please bear in mind that while it may seem trivial to write a response as simple as ‘yes’ into a space, this is very onerous as there are various aspects and requirements to consider.
The essence of this item is to ensure that there is adequate and secure means of making safe an appliance or a part of an installation for purposes of safely working on it, and further to ensure that it cannot be inadvertently switched on by others thus causing injury, death or fire.
For new installations, every aspect of these requirements must apply.
For existing installations, where the Certificate is issued in terms of the basic safety principles and reasonable safety, you will have to apply your mind and decide which are contrary to that, and which will not significantly improve safety.
The detailed requirements for Disconnecting devices are set out in sub-clause 6.9.
Firstly, some definitions of equipment employed as disconnecting devices:
Now, we will consider particular requirements for disconnecting devices:
It is NEVER allowed to break the neutral conductor without also breaking the associated live conductor at the same time.
For a single-phase appliance, both the live and neutral need to be interrupted simultaneously, but in a three-phase or multi-phase only the phases need to be interrupted.
Please note that you may interrupt the neutral as well but ensure that it is not ever interrupted while any of the phases are not! Energisation of phases, even momentary, without a secure neutral connection generally results in over voltages in single-phase circuits, which in turn causes expensive failures of single phase equipment.
As we’ll also see later, disconnection can be achieved by removing a plug from a socket, a lockable or a readily accessible switch disconnector.
Below are some examples of the lockable/locked possibilities and the subject of much debate. Any of these will prevent the inadvertent switching-on while someone is at risk. A keyring has been used for illustration purposes, but up to three padlocks can be used simultaneously; three different persons can lock out the same circuit, and it can only be switched back on once all three have released their locks.
Each DB must have its own Main or local switch disconnector, as the case may be. However, in the event that two adjacent enclosures are used to form a single DB, a common switch disconnector may be used, provided it is apparent and suitably marked.
Then we also need to consider the disconnecting requirements for fixed appliances, as found in 6.16 as follows:
General requirements for all appliances are given here. Specific requirements for types of appliances differ, and override these general requirements.
Below are more innovative ways of locking switchgear in the open position.
- Water Heaters (Geysers)
There are no additional requirements to the above 6.16.1 for the positioning of isolators for geysers, thus it can be within 1.5 m from the appliance (actually within 1.5m from the supply terminals would be preferable), or it may be on the DB provided it is lockable.
When doing CoCs for some older installations, particularly smaller flats, we often find geysers installed above the bathtubs inside Zone 1. In such instances, isolation from the DB suffices, and installing an isolator in the bathroom is not recommended or required, as it brings increased risks. Furthermore, ensure that any current-carrying parts are enclosed (ensure the cover over the terminals are securely fixed).
For new installations, it also needs to be protected by earth leakage, and this is recommended for all such instances.
- Cooking appliances
For stoves and ovens, the isolator needs to be within 500 mm (3 m if labelled clearly) of the appliance, in the same room, and between 0.5 and 2.2 m from the floor.
This is because in case of a grease fire, it must be possible to switch the supply off immediately. For the same reason, the isolator should also not be above the hob.
- Heaters and Air conditioners
While these may be supplied via a socket outlet, it is not the best practice.
For existing installations, a connection via a socket is not by itself contrary to the basic safety principles or reasonable safety thus provided all other requirements are met, this need not prevent the issuing of a CoC.
Any Unit rated at more than 16 A shall be on its own (Specific Aircon) circuit, but more than one may share a circuit, however, each must have its own isolator.
The desire of homeowners to install heated towel rails above baths in zone 1, or within reach from inside the bath in Zone 2 causes much confusion, particularly insofar as isolation is concerned.
The same rules as for water heaters or geysers as discussed above apply, but the added option B2 of using a class II (double insulated) appliance instead is added.
The requirement is that there must be secure means of disconnection, ensuring the safety of someone working on the motor or associated machinery. There are several options as set out below.
Below, two unconventional ways to secure (lock?) a meter box or DB without a padlock. Neither can be released inadvertently, both would require a tool or key to open.
- Electrode water heaters, steam generators and boilers
This part deals with appliances in which the live electrodes are immersed directly into water, and the passing of current through the water is used for heating the water.
As you surely can imagine there are many risks involved here, hence specific additional requirements are prescribed.
Fortunately, these are rarely encountered in the type of installations we normally deal with, and will mostly be found in commercial laundries, dry cleaners, hospitals or similar places.
As a result, this is usually not a major concern, but should you come across one, note the rules below.
Only once you have satisfied yourself that for each and every appliance and DB throughout the installation, the disconnecting devices break the phase conductors, and in single-phase installations the neutral as well, that each one is correctly located as set out above, you may enter ‘Yes’ in the appropriate space on the CoC.
Remember that the main purpose of isolation is to ensure that there is secure means of disconnection to safeguard persons working on the installation and appliances.
We recommend that you also double check the correct voltage and current rating of disconnecting devices at this point.
We will conclude Part 9 here, and in Part 10 we will attend to more inspections.