Cabinet and Terminal Facility TS2

This specification sets forth requirements for a TS2, type 1 traffic control cabinet assembly. All applicable sections of the NEMA standard publication, TS2, shall also be incorporated by reference.

The cabinet shall be constructed of minimum, .125 inch thick, natural aluminum. The cabinet shall be of clean cut design and appearance having no sharp edges, corners or protrusions. All welds shall accomplish in a workman like manner, and shall be smooth, neatly formed and free of cracks, blowholes or other irregularities. The cabinet top shall slope downward toward the rear of the cabinet to prevent rain accumulation. The main door of the cabinet shall occupy essentially the entire front and shall provide easy access to the interior. The door shall be fitted with a closed cell, neoprene gasket which shall fit tightly against a lip surrounding the door opening, such that entrance of moisture or dirt is prevented. The upper lip shall include a channel to prevent rain from entering the cabinet interior. The door shall be fitted with a strong, tumbler style lock, a three point latching mechanism and shall include a minimum 3/4” diameter handle, which shall include a hasp to allow the use of a padlock if desired. The door shall be hinged on its right side by means of a piano style hinge fabricated of non-corroding material. The main door shall be fitted with an automatically operating mechanism, capable of holding the door open at approximately 90, 125 and 150 degrees under windy conditions.

The roof of the cabinet shall incorporate an exhaust plenum and vent screen. The vent screen area shall face down to preclude entry of moisture.

The cabinet shall contain a ball bearing type, ventilating fan, having a minimum capacity of 100 CFM, controlled by a thermostat and shall include suitable dust filters for the capacity of the ventilating system. The thermostat shall be adjustable between 80 and 150 degrees Fahrenheit. The filters shall be of the dry type and easily replaced. Filters shall be located behind vent louvers located in the lower portion of the main door and shall be held securely in place.

The cabinet shall be equipped with a fluorescent light fixture located on the inside top of the cabinet, near the front edge. The fluorescent fixture shall accommodate a standard, FT15T12 lamp. The lamp shall be controlled by a door activated switch located near the top of the main cabinet door.

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. This auxiliary door shall incorporate a gasket seal in similar fashion to the main door. The panel behind the auxiliary police door shall contain two (2) switches to accomplish the following functions:

• (1) Change from normal operation to flashing, and vise versa.
• (2) Interrupt power to the signal heads.

Each cabinet shall include a terminal facility, which shall incorporate four major sub sections:

• Detector and communication interface terminal panel located on the cabinet left wall.
• Main terminal panel located on the cabinet rear wall.
• Power distribution panel located on the cabinet right wall.
• The detector terminal panel shall be fabricated of .125 inch aluminum and 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. A pressure style terminal block shall be included which shall serve as a termination point for all serial communication cables used to connect to the various components of the traffic controller system. There shall also be pressure style terminal block which shall serve as a termination and distribution point for all outputs from the cabinet power supply required to be connected to the detector racks. All terminals shall be permanently identified as to their circuit reference. All terminal blocks shall be “dead front” type.

All wiring between the detector loop terminal blocks and the detector rack assembly shall be color coded, twisted pairs. The detector loop terminal points associated with each detector rack shall be arranged in a single vertical row of 32 terminals on the detector panel. If multiple detector racks are required, then multiple, vertical rows of terminals shall be provided. The twisted pair connections to the detector racks shall terminate in a 37 pin “D” connector having a positive latch to ensure a reliable connection to the detector rack.

All internal cabinet serial data shall be carried on cables specifically designed for use with RS485 circuits, and all pairs shall be twisted and color coded. Cables shall be of sufficient length to allow rearrangement of the various components within the cabinet, but shall be coiled neatly to present a workman like appearance.

The main terminal facility panel which shall be located on the rear wall of the cabinet shall include wired socket positions for a flasher, load switches, flash transfer relays, controller I/O terminals and buss interface units (BIU’s). It shall be fabricated of .125 brushed aluminum. Each socket or terminal point shall be silk screened with its circuit reference identification.

The main terminal facility panel shall include pressure type terminal blocks, located horizontally along the lower edge for the connection of all field signal wiring. Immediately above the field hookup terminal blocks, a second series of terminal blocks shall provide a simple method of flash programming which shall involve only the use of simple hand tools. All connections between the field hook up terminal blocks and the flash program blocks shall be color coded, and the wiring diagram shall include clear instructions to facilitate the programming of flashing operation. Flash programming shall not involve any changes of the field signal wiring. All terminal blocks shall be clearly and permanently identified as to their function and circuit reference.

Terminal facility panels shall be available in four configurations, as prescribed by NEMA specification TS2, and described as follows:

• Configuration 1: 4 Load switch positions; 2 Flash transfer relay positions; 2 BIU positions; 1 Flasher position.
• Configuration 2: 8 Load switch positions; 4 Flash transfer relay positions; 2 BIU positions; 1 Flasher position.
• Configuration 3: 12 Load switch positions; 6 Flash transfer relay positions; 2 BIU positions; 1 Flasher position.
• Configuration 4: 16 Load switch positions; 8 Flash transfer relay positions; 2 BIU positions; 1 Flasher position.

A bracket or shelf extending at least half the length of the load switch or flasher shall support all load switch and flasher positions. All BIU positions shall be provided with rack style mounting with card edge guides for both the upper and lower edges of the BIU. Each BIU rack position shall have its address pins pre-wired to define the proper operation for each position, and to allow interchange of BIU’s without the need for additional programming.

Each flash transfer relay position shall include an RC network, wired in parallel with the coil connection pins.

An expandable, braided, nylon mesh jacket to provide abrasion protection and to ensure a neat appearance of the assembly shall protect all cables within the cabinet assembly, except the serial data cables. All cables shall be securely fastened in place to provide strain relief.

All main terminal facility panels shall include connection cables to a Type 16 Malfunction Management Unit (MMU), as defined by NEMA specification TS2.

A power distribution panel shall be located on the right wall of 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, lightning arrestor and a mercury buss relay to control the AC power to the signal heads. The lightning arrestor shall be EDCO model ACP-340. The mercury buss relay shall be of the normally open type, and shall have an RC network wired in parallel with its coil circuit. A neutral buss bar having a minimum of 13 positions shall be provided for easy connection of all signal neutral wiring.

The cabinet shall contain an internal test panel which shall contain a switch labeled “Stop Time – Run – Normal”, to facilitate troubleshooting of the controller equipment. In the “Stop Time” position, all timing functions of the controller shall be suspended. The “Run” position shall allow the controller timing to operate without regard for the condition of any other devices within the cabinet. In the “Normal” position, the controller timing functions shall operate normally so long as all other equipment or switches are operating normally. Operation of flash switches or the detection of a fault by the MMU shall immediately apply a stop time input to the controller.

The test panel shall also contain a duplex convenience outlet, separately fused at 15 Amps, and wired directly to the AC input to the cabinet, such that power will be supplied to the outlet even with the main cabinet circuit breaker in its off position.

The cabinet shall include a cabinet power supply meeting the requirements of NEMA specification TS2. The power supply shall be completely enclosed in a brushed aluminum housing and shall be shelf mounted. It shall provide the following voltage and current outputs:

• +12 VDC +/- 1 VDC, 2.0 A
• +24 VDC +/- 1 VDC, 2.0 A
• 12 VAC, 0.25 A

Outputs shall be fused with slow blow fuses of the ratings indicated.

AC power input shall be protected against over current with a 2 Amp slow blow fuse.

LED indicators on the front panel shall denote the presence of 12 VAC, 24 VDC and 12 VDC and the 60 Hz reference signal Test points for logic common and +24 VDC shall also be provided on the front panel.

The cabinet shall include a rack or racks for vehicle detector amplifiers.