Gauteng Electrical Inspection Authority
It is surprising to me that many of the installations in which I am involved in investigating compliance, that the concept of ‘reasonably safe' remains just that - a concept.
In dealing with current Regulatory requirements, every existing installation, which is tested and inspected for the issue of a Certificate of Compliance, must comply with the fundamental safety requirements of the current version of the SANS 109142-1 Wiring Code.
Herein lies the concept of ‘reasonably safe' - and, in my experience, many registered persons only have a vague notion of what must be done!
Before dealing with particular items that seem to be commonplace in the electrical industry, I thought I would deal with the overall requirements and history of this element of compliance:
Let's take a closer look at SANS 10142-1, clause 5 - Fundamental Requirements:-
The requirements detailed under this clause have evolved over the last 34 years of various published editions of the wiring standard. This evolution has resulted in many previous specific clauses being incorporated into a general clause over the years as electrical installations became more intricate.
Simplistically, when testing an existing installation, specific requirements for certain parts of the ‘old' electrical installation were indeed covered by a specific standard at the time of installation. Although it may be perceived that this requirement no longer applies to the installation, it must be carefully evaluated in terms of the fundamental requirements clause, which will be applicable.
Clause 5 starts with a note:-
NOTE: - This clause contains the general safety principles applicable to electrical installations.
Is this reference only applicable to some installations? No! It is applicable to all installations, both new and existing and irrespective of the age of the installation.
Having got this out of the way, let us have a look at a simple case of compliance:
A registered person is faced with a situation where an electrified gate motor has been previously been installed. The date of installation is unknown, but let us assume for argument sake that the motor was installed in 1979 at the time of construction of the electrical installation. During the inspection (now 2012), it has been detected that no switch disconnector had been installed - is it a requirement for a switch disconnector to be installed?
I am told in many instances - incongruous as it may seem - that as this motor was ‘existing' and was previously passed by ‘an inspector' that this part of the electrical installation complies as is! It is, in other words, ‘reasonably safe' and meets with the ‘fundamental requirements of the current edition of the Wiring Code'.
Let us then go back to the Wiring Code in 1978 and see what it has to say regarding this part of the installation when it was installed.
SABS 0142-1978 Clause 6.4.2 Control Gear (Motors and Control Gear) -
Clause 6.4.2.a - A motor, unless it is integral with a submersible pump, shall be supplied from a switch disconnector that is visible from the motor or is lockable.
Well now, had this been passed by an ‘inspector' back then, I would cry foul as the installation of the motor was not compliant back then. So having determined that the installation of the motor with no switch connector back then did not comply, is it any closer to compliance in 2012 as is?
Fundamental Requirement Clause 5.2.7 (SANS 10142-1:2009 Ed 1.7) states:-
Basic Provisions - Disconnecting Devices
An installation shall have disconnecting devices that allow the installation to be disconnected for maintenance, testing, fault detection or repair. In the case of circuits or items of equipment, additional disconnecting devices could be required to allow disconnection for maintenance, testing, fault detection or repair of such circuits or equipment.
How do we know if these items of equipment referred to require such disconnecting devices?
Well, the current Wiring Code is specific:
Clause 6.16.5.1.5 - Motor protection and control:
6.16.5.1.5 Each motor shall be supplied by a manually operated disconnector or any other manually operated disconnecting arrangement such as a withdrawable circuit breaker, a removable link, a fuse or by the removal of a plug from a socket-outlet, which provides at least the same isolating distance, for the sake of safety, as a disconnector that is
a) readily accessible and mounted on or next to the motor, or
b) visible from the motor, or
c) lockable in the open position, or
d) housed in a lockable enclosure other than a distribution board.
The SABS 0142-1978 Clause 6.4.2 Control Gear (Motors and Control Gear) also required the installation of a disconnecting device!
No rocket science required here - a switch disconnector is required in order for a valid Certificate of Compliance to be issued.
Faced with the above, an argument of reasonable safety based on a premise of ‘that which is existing' holds no water.
In next month's column I will deal with some other common issues, with which some of my colleagues in this industry seem to have difficulty.
mark@geia.co.za
