25.2 Recommendations for mains power supplies
25.2 c) ‘To facilitate local isolation during maintenance, suitable means should be provided for the double pole isolation of the low voltage supply circuit that serves the power supply and the control equipment(see 29.2e)’
29.2 Electrical safety recommendations
29.2 e) ‘ Means should be provided for double pole isolation of the mains supply to all parts of the system; the isolation facilities should be suitably sited , in the vicinity of the equipment served, for use by maintenance technicians without the need for access to remote parts of the building. It should be possible to lock the facilities in both the normal and isolate positions to prevent unauthorised use. See Clause 25.’
29.2 f) ‘Every isolator, switch and protective device that can isolate the supply to the fire alarm system, other than the main isolator for the building, should be labelled either; FIRE ALARM; Protective device serving only the fire alarm with no switch FIRE ALARM, DO NOT SWITCH OFF; in the case of a switch (whether incorporating a protective device or not) that serves only the fire alarm circuit.
29.2 g) Every isolator, switch and protective device that is capable of disconnecting the mains supply to the fire alarm system should be situated in a position inaccessible to unauthorized persons or be protected against unauthorized operation by persons without a special tool.
Note 4 A special tool, may for example, be a key actuator (sometimes called “secret key”) for a mains switch device. Disclaimer: The information given on this data sheet is for guidance only and is not intended to be comprehensive. Any person using the product for any purpose other than the intended purpose without obtaining the written confirmation from Zeta Alarms Limited as to the suitability of this product does so at their own risk As Zeta Alarms Limited has no control over the treatment of the product, the standards of preparation or other factors affecting the use of the product, company cannot be held responsible for its performance. Nor would it accept any liability whatsoever or howsoever arising from the use of the product unless specifically agreed in writing with an authorized representative of the company. The information contained on this sheet may be modified, and updated by the company from time to time, and without notice in the light of experience and the Zeta Alarms Limited policy of continuous product improvement.
