I got into a discussion about circuits for battery packs and exit signs. Some of my guys questioned the arrangement of circuits and the application of rule 46-400. Is it OK to use a local lighting circuit to supply battery packs and exit signs? The battery packs and exit signs could not be controlled by a switch of course. Maybe a better way to put or pose the question would be " Why shouldn't battery packs and exit signs be fed from a local lighting circuit?". What technical problems could arise from such an installation? Sure could use some expert advise on this one. Thanks Bill
Is it OK to use a local lighting circuit to supply battery packs and exit signs?
No it is not ok. Rule 46-400(1)(2) is pretty clear about that
Maybe a better way to put or pose the question would be " Why shouldn't battery packs and exit signs be fed from a local lighting circuit?". What technical problems could arise from such an installation?
Well they shouldn't be fed from a local lighting circuit because it would be illegal. Maybe the intent is to eliminate as many potential mistakes as possible such as having a switch or timer in the circuit. Who knows, maybe sometime down the road someone will decide to place the complete lighting circuit on a timer without realizing the exit signs and emergency lighting is on the same circuit. I am just taking a guess at the reasoning though.
Re: 46-400 exit signs#102174 04/25/0510:31 AM04/25/0510:31 AM
Rule 46-400 is pretty clear. I understand that somewhere down the road someone might install a switch, timer or ?... Let's look at it this way. Scenario one. Tie the battery packs to the local lighting lighting circuit. Install the exits on a separate circuit as per 46-400. A failure causes the OCP for the exit sign circuit to trip. The exit signs are not illuminated any more. Nobody really notices the exit signs are out for a period of time. A situation arises where the illumination of the exit signs is critical. BUT they are not on..... Scenario two... Exit signs and battery packs are tied into a local lighting circuit. A fault causes the OCP to trip. The exit signs are now illuminated through the battery packs... Can we have some more discussion on this topic please.
(1) Where exit signs are connected to an electrical circuit, that circuit shall be used for no other purpose.
(2) Notwithstanding Subrule (1), exit signs shall be permitted to be connected to a circuit supplying emergency lighting in the area where these exit signs are installed.
(3) Exit signs in Subrules (1) and (2) shall be illuminated by an emergency power supply where emergency lighting is required by the National Building Code of Canada.
Rationale for Rule 46-400. This Rule establishes the requirements pertaining to the power supply for exit signs.
Intent for Rule 46-400. Building codes provide the requirements for the location of illuminated exit signs.
If an exit sign is required by the building code, we intend that the power supply for the exit sign be provided from a branch circuit that supplies only other exit signs or a circuit supplying emergency lighting. We also intend that, in the area where exit signs are installed, and where emergency lighting is required by the National Building Code of Canada or local building codes, exit signs be illuminated by an emergency power supply. The exit signs shall be permitted to be connected to the emergency lighting in the area. This requirement ensures that the exit sign will be lit whenever the emergency lighting is energized.
The note in Appendix B cautions that the circuit supplying both emergency lighting and exit signs should not be controlled by a switch, time clock, or other means.
ONTARIO BULLETIN #46-1-4
July 1998 Supersedes Bulletin 46-1-3 (November 1996)
Emergency Lighting and Exit Signs
Rules 46-304 and 46-400 (page 196)
The Ontario Building Code prescribes the supply conditions for electric emergency lighting and exit signs in Articles 3.4.5, 18.104.22.168, 9.9.10 and 9.9.11. The wiring requirements for such equipment are in Section 46 of the Ontario Electrical Safety Code.
Section 46 applies to buildings where emergency lighting and exit signs are required by the Ontario Building Code.
Rule 46-304 (4) requires:
“Unit equipment shall be installed in such a manner that it will be automatically actuated upon failure of the power supply to the normal lighting in the area covered by that unit equipment.”
This is not always practical, in areas such as large retail areas, a gymnasium in a school or a manufacturing area in a factory. In these areas most of the circuits could fail and the light levels would be such that persons within could safely exit the building.
For buildings or large areas separated by fire walls, within the scope of Part 3 of the Ontario Building Code, such as the retail area in a store , gymnasium in a school or a manufacturing area in a factory, the phrase "the failure of the power supply to the normal lighting in the area covered by unit equipment" is interpreted to mean failure of the regular power supply to the building. An acceptable method to satisfy the requirement is to supply the unit equipment from a branch circuit in the panel supplying the lighting.
There are separate requirements for the activation of emergency lighting and exit signs in buildings within the scope of Part 9 of the Ontario Building Code.
Part 9: Buildings
Unit equipment installed in buildings within the scope of part 9 of the Ontario Building Code , shall be installed in such a manner that it will be automatically actuated upon failure of the power supply to the normal lighting in the area covered by that unit equipment.
Exit Signs Installed where not required by the Ontario Building Code
There are no special requirements in the Ontario Electrical Safety Code for exit signs installed voluntarily.
To eliminate controversy in the field and to assure a degree of uniformity in wiring arrangements, the following practices are acceptable for wiring exit signs not required by the Ontario Building Code:
(1) Conductors supplying exit signs shall be installed in accordance with Section 12.
(2) Appliances, lamps, or devices other than those required for exit signs shall not be supplied by the branch circuit supplying the exit signs.
(3) Branch circuit overcurrent and control devices shall be operable by or accessible to authorized persons only.
To assure that exit lights are not inadvertently switched off in an emergency, it is desirable that branch circuit connections be made as close to the service entrance as possible.
Responsibility for interpreting the Ontario Building Code rests with the municipal building departments, which should be consulted on questions concerning the requirements of the building code concerning the necessity for emergency lighting and exit signs in any particular building.
Tony Moscioni Electrical Inspector Electrical Safety Authority
Bill I know you wanted to have some more discussion about the benefits of putting the exit lights on a lighting circuit. Tony did a terrific job pointing out all the rules that tell you not to do it. But if I consider your scenario and it accidentally gets connected to a timed or switched circuit the exit lights would go onto battery when you switch out the lights and leave at night. Depending on the type of occupancy the lights could be required to stay on for as little as 30 minutes, that means dead batteries when you come in the morning and a potential for problems. I think you are trying to compare the rational of connecting a smoke detector in a residence to lighting circuit. This works great in a house, if the lights are out you have no smoke detector protection and know something is wrong right away. In theory it might make sense with exit lights, but I think the fire code protects us from this sort thing by requiring the owner/operator/tenant of a facility to test these lights monthly
Emergency lighting 22.214.171.124. (1) Pilot lights on emergency lighting unit equipment shall be checked monthly for operation. (2) Emergency lighting unit equipment shall be inspected monthly to ensure that (a) the terminal connections are clean, free of corrosion and lubricated when necessary, (b) the terminal clamps are clean and tight as per manufacturer's specifications, (c) the electrolyte level and specific gravity are maintained as per manufacturer's specifications, and (d) the battery surface is kept clean and dry. (3) Emergency lighting unit equipment shall be tested (a) monthly to ensure that the emergency lights will function upon failure of the primary power supply, and (b) annually to ensure that the unit will provide emergency lighting for a duration equal to the design criteria under simulated power failure conditions. (4) After completion of the test required in Clause (3)(b), the charging conditions for voltage and current and the recovery period shall be tested to ensure that the charging system is in accordance with the manufacturer's specifications.