I have recently tested an installation, a baggage handling system. I tested from the Local mains (fed from substations) to each control panel for the baggage handling system. The control panel has an isolator and from that isolator it feeds busbars in the panel from which the breakers for the various parts of the baggage handling system are are controlled. The PLC controls contractors which obviously control various parts of the systems motors etc etc.
Now because "SANS 10142 does not intend to cover LV control circuits of machinery or system components that are external circuits between separately installed parts of the machinery or system components" I'm sure the out going circuits from the control panel (motor circuits) and the control cabling is not essentially covered by SANS 10142 and therefore can't be covered by a COC.
But I see in "OCCUPATIONAL HEALTH AND SAFETY ACT, 1993
ELECTRICAL INSTALLATION REGULATIONS" that the definition of an electrical installation is-
"electrical installation" means any machinery, in or on any premises, used
for the transmission of electricity from a point of control to a point of
consumption anywhere on the premises, including any article forming part of
such an electrical installation irrespective of whether or not it is part of the
electrical circuit, but excluding
(a) any machinery of the supplier related to the supply of electricity on the
(b) any machinery which transmits electrical energy in communication,
control circuits, television or radio circuits;
(e) an electrical installation on a vehicle, vessel, train or aircraft; and
(d) control circuits of 50 V or less between different parts of machinery or
system components, forming a unit, that are separately installed and
derived from an independent source or an isolating transformer;