2009-192 - Laserfiche WebLink

Home Browse Search

FORT PIERCE ENGINEERING, INC. IRC Maintenance approved by the electrical design engineer. Install suppressor in a listed enclosure near the electrical panelboard, and trim excess lead lengths. Wind small coil in the branch circuit conductorjust downstream of the suppressor connection. Coil to be 5 to 10 turns, about 1 " diameter, and securely tie-wrapped. This series impedance will improve the effectiveness of the suppressor in clipping fast rise time voltage transients. On DC Circuits Extending Outside Building: Adjacent to the FACU, and also near point of entry to outlying building, provide "pi"-type filter on each leg, consisting of a primary arrestor, series impedance, and a fast acting secondary arrestor that clamps at 30v-40v. Some acceptable models : Innovative Technology D2S33-2ML, Simplex 2081 -9027/-9028, Transtector TSP8601 , Ditek DTKxLVL series, Citel America B280-24V, Leviton 3824-OWM, Northern Technologies DLP-42. Submit data on others to the engineer for approval . UL 497B listing is normally a prerequisite for their consideration. Devices using only MOV active elements are not acceptable. 1 . 14 Systems are to be provided with a separate and independent source of secondary power. The system shall have a minimum of 24 hours secondary power capacity, plus 5 minutes of full alarm load. Include a copy of system battery sizing calculations with the shop drawing submittal to the engineer. Use manufacturer's battery discharge curve to determine expected battery voltage after 24 hours of providing standby power. Then use calculated Notification Appliance Circuit current draw in the alarm mode to determine expected voltage drop at EOL, based on conductor resistance per manufacturer's data sheet or NEC 2005, Table 8. Remember to double the ohms per foot since two conductors are required to power the circuit. Also, add any inherent voltage drop caused by the system ' s power supply. The voltage drop at EOL must not exceed 14 % of the expected battery voltage, after the required standby time plus alarm time. (Typically, for a 24 volt system, this limits the voltage drop from the battery to the EOL to 3 volts). Determine "worst case" voltage at far end of each NAC, by subtracting its calculated V-drop from the expected battery voltage. The result must be no less than the minimum listed operating voltage for the alarm notification appliances used. All of these calculations must be placed on a dedicated sheet of as-built drawings for future reference by fire alarm service technicians NAC voltage drop is to be verified during system tests. 1 . 15 Fire/smoke/CO detectors used shall be of the following types: 1 ) photoelectric smoke detectors for office building ceilings; 2) photoelectric duct smoke detectors for HVAC ducts; 3) 135°C heat detectors and CO warning system for maintenance building and storage bays. 1 . 16 Manual pull stations shall be provided at each point of egress in the office building and in accordance with the prescriptive requirements of NFPA 72 in the maintenance building and storage bay building. 2.0 Reserved. 3.0 Monitoring of Signals by Supervising Station : 16965 FIRE DETECTION & ALARM SYSTEM Page 4 OF 10