N.Y. Comp. Codes R. & Regs. tit. 9, § 1500.5 – Electrical requirements.

(1) New electrically operated interior fire alarm systems shall be constantly supervised by the continuous flow of an electric current through the system. Any interruption of electric current through the system or any circuit trouble shall cause a trouble signal to be sounded which is audible to an authorized person satisfactory to the department. Such trouble signal shall sound until silenced by manual means or restoration of supervisory current flow by correction of circuit trouble. Silencing of trouble signal by manual means shall automatically transfer such signal to a red lamp. Trouble signal shall be operated from the auxiliary source of power, except that where a single source of power is permitted, the trouble signal shall be operated from a side or phase of the power supply separate from that operating the signaling system. Sounding devices not readily susceptible to electrical supervision, such as vibrating bells, will not be required to be so supervised provided such sounding devices are alternately connected to separate circuits and are approximately equally distributed throughout the building.
(2) New electric equipment shall be designed and constructed to operate satisfactorily at voltages of 25 per cent above or below normal, or in accordance with generally accepted standards as set forth in the appendix to these rules.^*
(3) Circuits used for the transmission of alarms shall be used for fire protection purposes only and shall be arranged and installed so that there can be no interference with the operation of the sounding devices.
(b) Electrical wiring.
(1) New electrical wiring for fire alarm systems shall have a rating of not less than 300 volts, except that on systems designed for operation at 50 volts or less, electrical wiring having a rating of not less than 150 volts may be used for circuits where the input is limited to 100 volt-amperes with current not exceeding five amperes.
(2) Sizes of such electrical wiring shall be in accordance with generally accepted standards as set forth in the appendix to these rules. ^*
(3) New electrical wiring shall be satisfactorily protected against damage due to corrosion, moisture or mechanical injury.
(4) New electrical wiring shall be protected by a metallic raceway or armor, except that such raceway or armor shall not be required for wiring installed at least seven feet above the floor for circuits where the input is limited to 100 volt-amperes with current not exceeding five amperes on systems designed for operation at 50 volts or less.
(5) New raceways, boxes, fittings and cabinets containing fire alarm conductors shall not contain wiring used for any purpose other than fire protection.
(c) Power supply.
(1) A new fire alarm system shall be supplied with electrical energy from a main source and, in case of failure of the main source, from an auxiliary source, except that where electric service of three, four, or five-wire type is obtained from a reliable underground network distribution system, the auxiliary source shall not be required. The following are acceptable sources for main and auxiliary power supplies: central electric power station (local utility company) and an electric generator or one set of storage battery units continually charged; two electric generators; two sets of storage battery units continually charged; one electric generator and one set of storage battery units continually charged. A sufficient number of heavy duty primary batteries of suitable type and of adequate capacity shall be permitted as the auxiliary source of power supply when approved by the department.
(2) One source of power shall be connected to the fire alarm system at all times. The auxiliary source shall be automatically controlled so that when the primary source fails, the auxiliary source will be connected automatically to the system and the transfer shall be indicated by a signal. Immediate steps shall be taken to return the system to the primary source of supply.
(3) A new fire alarm service connection to a central power station supply shall be made as close as practicable to the main service entrance with either of the following arrangements: connection made on the street side of the service switch, or connection made on the house side of the meter and as close to the meter as possible without intervening interrupting devices.
(4) Between fire alarm service connection, as described in paragraph (3) above, and the control board, only one set of protective devices will be permitted; no additional devices are permitted.
(5) A new fire alarm service connection to a power supply other than that from a central power station shall be made with only one set of protective devices in addition to any set of devices used to protect the main source of supply.
(6) Fire alarm system protective devices shall be contained in a locked or sealed metal cabinet which shall be conspicuously identified. The use of open link or screw plug fuses shall not be permitted.

(a) General.