Last edit: 19/06/2023
C22.2 N°286: 2023 is the now reference standard for the construction of Industrial Control Panels in Canada. It is the equivalent of UL 508A for USA.
In the past, the reference Standard was C22.2 N°14: Industrial control equipment. But that was not really a Standard for the conformity of control panels for machinery, since it was written for the conformity of electrical components like contactors (manual motor controllers in North American technical language).
The second edition was published in 2017 and it contained a different approach to cable ampacity, compared with UL 508A. The latter does not require cable ampacity compensation for more than 3 cables next to each other. That means a copper AWG 10 conductor has an ampacity of 30 A; please refer to Table 28.1 of UL 508A. If 9 conductors run inside a control panel wiring thought, the ampacity is still 30 A.
Table 7 of C22.2 N°286 second edition was quite different comparted with Table 28.1 of UL 508A. A copper AWG 10 conductor had an ampacity of 27 A if the control panel was ventilated. That ampacity has to be corrected for the number of conductors in a wiring thought according to table 8. That means, if 9 cables run inside a control panel wiring thought, the ampacity becomes 19 A: it is downgraded!
An extreme situation was for a non ventilated panel: in case of 9 copper AWG 10 conductors running in a wiring thought, the ampacity becomes 13 A! Quite a difference with respect to 30 A according to UL 508A.
The new edition (third) of C22.2 N° 286 was published in June 2023. It has a completely revised Table 7, quite similar to Table 28.1 of UL 508A. From this point of view the two standards are aligned.
New aspects contained in the third edition of C22.2 N° 286:
- expansion of requirements for connection means;
- additional requirements for ferrules and pigtail adapters;
- clarifications for requirements for Class 2 (non-safety control devices) components;
- additional compliance criteria for panels and assemblies for use outside of the assumed 0-40° C ambient range;
- expansion of the short-circuit current rating {SCCR) determination criteria;
- revisions to required SCCR markings;
- removal of motor control centre requirements; and
- addition of strain relief and abnormal operations tests.