IET logo
 
IET
Decrease font size
Increase font size
Topic Title: Domestic Smoke Alarm Circuit
Topic Summary: 1.00mm2 or 1.5mm2
Created On: 05 October 2017 09:22 AM
Status: Read Only
Linear : Threading : Single : Branch
 Domestic Smoke Alarm Circuit   - sdltn - 05 October 2017 09:22 AM  
 Domestic Smoke Alarm Circuit   - broadgage - 05 October 2017 09:30 AM  
 Domestic Smoke Alarm Circuit   - AJJewsbury - 05 October 2017 09:40 AM  
 Domestic Smoke Alarm Circuit   - sdltn - 05 October 2017 10:45 AM  
 Domestic Smoke Alarm Circuit   - WiredScience - 05 October 2017 12:12 PM  
 Domestic Smoke Alarm Circuit   - AncientMariner - 05 October 2017 07:01 PM  
 Domestic Smoke Alarm Circuit   - Zoomup - 07 October 2017 09:01 AM  
 Domestic Smoke Alarm Circuit   - geoffsd - 05 October 2017 07:15 PM  
 Domestic Smoke Alarm Circuit   - geoffsd - 07 October 2017 01:03 PM  
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 05 October 2017 09:40 AM
User is online View Users Profile Print this message



AJJewsbury

Posts: 15839
Joined: 13 August 2003

Requiring 1.5mm2 for a simple smoke alarm circuit doesn't seem sensible (the DPC for the 18th Ed tries to side-step the issue by claiming that 'small power' circuits (e.g. bathroom fans) can count as 'lighting') so personally I wouldn't have a problem with smoke alarms wired in 1.0mm2.

In terms of showing compliance with the letter of the 17th Ed, I'd suggest either putting the smokes on the same protective device as a frequently used lighting circuit (often recommended anyway as it reduced the chances of the smokes supply being interrupted for an extended length of time - either accidentally or deliberately) or (looking a bit further down table 52.3) claim that the smoke alarm circuit comes under 'signalling and control' rather than 'power' and so the 1.5mm2 limit doesn't apply (but 0.5mm2 instead).

- Andy.
Statistics

New here?


See Also:



FuseTalk Standard Edition v3.2 - © 1999-2017 FuseTalk Inc. All rights reserved.

..