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Cabinet and Terminal Facility TS1 The controller and all associated equipment shall be furnished completely housed in a sturdy aluminum cabinet. The cabinet shall be of clean cut design and appearance having no sharp edges, corners or projections. The size of the cabinet shall be such as to provide ample space for housing the controller and all associated electrical and auxiliary devices. A hinged door shall be provided permitting complete access to the interior of the cabinet. The door shall encompass essentially the entire front of the cabinet. The cabinet is to be weather proof and dust tight. The door shall be provided with a strong lock and two sets of keys. The door hinges and pins shall be of a non-corroding material. The cabinet shall contain strong mounting shelves for the support of the controller and associated equipment. A solid-state two circuit jack mounted flasher with a rated load of 10 amps per circuit shall be supplied. Where additional load is required, more than one flasher will be provided. The flasher shall flash at the rate of 50 to 60 flashes per minute and be of the "zero switching" type to prevent radio interference. The cabinet shall contain a ventilating fan controlled by a thermostat and shall include suitable dust filters for the capacity of the ventilating system. The filters shall be of the dry type and easily replaced. In addition to the main door of the controller cabinet, there shall be an auxiliary door provided in the main door with a lock and standardized police key. The panel behind the auxiliary police door shall contain two (2) switches to accomplish the following functions:
A convenience outlet and trouble lamp receptacle shall be furnished with each cabinet. The cabinet shall contain an internal test panel which shall have switches as follows:
Each cabinet shall include a terminal facility which shall incorporate four major sub sections:
The detector terminal panel shall incorporate sufficient terminals for the connection of all incoming loop feeder cables, all pedestrian pushbutton wiring and all preemption detector field cables. All field connections shall terminate on pressure style terminal blocks rated at not less than 30 amps per circuit. A ground buss to facilitate the connection of feeder cable shield wires shall be provided adjacent to the field terminal strips. All detector connection wiring shall be terminated on this panel. Terminal points for AC+, AC- and phase greens shall be provided. The "D" connector panel shall provide sufficient terminals for the connection of all incoming and outgoing circuits from the controller "D" harness. All circuits shall terminate on pressure style terminal blocks rated at not less than 30 amps per circuit. The main terminal panel shall include the following: A. Terminal points for all input/output connections for the "A","B" and "C" connectors from the controller. B. Wired positions for a two circuit NEMA flasher and three circuit NEMA load switches in the following quantities:
D. Termination points for all field signal wiring. All wiring to and from the NEMA "A", "B" and "C" connectors shall be routed directly to, and shall terminate on the rear of the main terminal panel by means of a soldered connection to a feed-through style terminal block such that all input/output circuitry shall be accessible from the front of the panel for test or hook up purposes. To insure the reliability of these circuits, no plugs, sockets, printed circuit boards or push on type connectors shall be inserted between the controller plugs and/or sockets and the terminal strip points at which these wires are terminated. Additionally, all load switch input circuits and conflict monitor control circuits shall terminate by means of solder connections to these same terminal strips. Thus it shall be possible to make the interconnections between the controller, load switches and conflict monitor by means of a simple system of jumpers located on the front of the main panel such that alterations may be easily accomplished. All load switch, flash transfer relay and flasher sockets shall be wired with solder connected conductors, properly sized as to their function. Each load switch socket AC+ input shall be wired individually to the main AC signal buss with a minimum 16AWG conductor.All field signal connections shall be terminated to a heavy duty, barrier style terminal strip having minimum 10-32 screws. All terminal connection points shall be clearly identified as to their function and referenced to the terminal facility wiring diagram by means of clear, silk screened legends located on the panel adjacent to the appropriate terminal point. All signal phases shall be equipped with provisions to allow the selection of either red or yellow flash programming. Flash programming shall be accomplished by the simple rearrangement of jumpers which shall require nothing more than simple hand tools to perform. A power distribution panel shall be located on the right side wall of the cabinet in the case of four and eight phase terminal facilities. In the case of a two phase terminal facility, all of the following specifications shall be applicable except that the componentry shall be incorporated on the main terminal facility to conserve space within the cabinet. The assembly shall contain provisions for the connection of the incoming AC service, a main cabinet circuit breaker, a radio interference line filter having a circuit breaker, a lightning arrestor and a mercury buss relay to control the AC power to the signal heads. The main AC service circuit breaker shall be rated as follows:
The lightning arrestor shall be of the hybrid type rated at 20,000 amps and capable of clamping such a surge to a peak of not greater than 350 volts without regard for the rise time of the surge. The arrestor shall be totally of solid state design, with no gas tube type devices of any kind and shall be of two stage unit providing separate protection for the controller and monitor unit. A minimum 200 microhenry inductor shall be incorporated between the equipment line in and equipment line out terminals. The arrestor shall be epoxy encapsulated in a flame retardant material. The mercury buss relay shall have a current carrying capacity at least as great as the main circuit breaker and shall be of the normally open type wired such that under normal stop and go operation of the controller the relay shall be held energized and shall allow current flow to the load switches under that condition. De-energization of the buss relay shall disconnect power to all load switches. Each cabinet shall be equipped with suitable rack(s) to accommodate the required quantity of two channel detector units. The rack(s) shall be fabricated of aluminum and shall provide adequate support and protection for the detector units while at the same time allowing for sufficient air flow through the rack(s) to prevent heat build up. Each rack shall mount no more than eight two channel detector units and an associated power supply. Multiple racks shall be provided if more than eight detector units (sixteen channels) are required. The rack(s) shall be equipped with card edge type socket connectors spaced on 1.25" centers to connect the detectors to the system. All wiring to the detectors shall be done through these card edge connectors. Each detector unit position within the rack shall be fitted with a non conductive card guide on both the top and bottom to guide the card into the socket. Card guides shall be held positively in place in the rack members. Each rack shall be equipped with a plug in power supply capable of providing 24 volt, DC power to a minimum of eight, two channel detector units. Power supplies shall be four channel devices having each channel separately fused to provide protection from over current conditions. Each channel shall be equipped with an LED pilot light to provide a visual indication of channel operation.
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