Not necessarily,
NBC/OBC requires that an EOL be installed no higher than 1800mm from grade. Plate or no plate. If your bell/horn/strobe is at 2300-2400mm, the EOL has to be located in a separate enclosure, at a max height of 1800mm, to be acceptable. If the circuit had only one bell, and was at 1800mm, then it would be deemed acceptable. Audible devices cannot be installed at 1800mm, this you should never find an EOL in one.
Hope this clarifies everything.
This is not correct.
First off, the NBC/OBC does not give height requirements for EOL’s or any other fire alarm device other than manual pull stations. All installation requirements are in CAN/ULC-S524.
And secondly, the height requirement stated in CAN/ULC-S524 of 1800mm is overridden when the EOL is located in a device if it's the only device on a circuit. Clause 10.1.1 starts with "except as permitted by clause 10.1.2" meaning that everything following in that clause does not apply if you are applying clause 10.1.2 . So no height requirement and no separate enclosure. We only have to label the device saying that the EOL is inside it as per 10.1.4.
Here is the actual verbiage of the standard.
10.1 END-OF-LINE DEVICES
10.1.1 Except as permitted by Clause 10.1.2, end-of-line devices for electrical supervision shall be
located in a separate enclosure, installed less than 1800 mm above finished floor level measured from the
centre of the end-of-line device, and located beyond the last device in the circuit or terminated in a control
unit or transponder.
10.1.2 End-of-line devices for one field device on a circuit may be located within that field device provided
that the end-of-line voltage can be tested.
10.1.3 End-of-line devices shall have an identifying label securely attached to the front of the cover plate,
listing the zone served.
10.1.4 Where end-of-line devices are located within a field device, as permitted by Clause 10.1.2, an
identifying mark visible after installation shall be affixed to the field device.