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the equipment which must be removed shall require the use of only simple hand tools to
accomplish the removal. To the extent practical, the layout of equipment and terminals
within the various cabinets furnished shall be identical from cabinet to cabinet. The
cabinet shall have a hinged, fold-down back panel to permit easy access to the rear
terminals.
9.1.7
Lamp and Door Switch
The cabinet shall be equipped with two (2) 15-watt (minimum) fluorescent lamp
assemblies, complete with lamps, located to illuminate the face of the equipment in the
cabinet and the field terminals. The lamps shall be controlled by a door-actuated switch
which turns the lamps on when the door is open and off when the door is closed. The
lamp assemblies shall utilize standard lamps that are readily available from commercial
lamp outlets.
9.1.8
Thermostat
The cabinet shall be equipped with an adjustable thermostat located in the upper
portion and connected to control the fan. It shall be manually adjustable within the
range of at least 26 to 77 °C and shall have a calibrated scale. The thermostat shall have
contacts rated sufficiently for use with the fan. The thermostat shall turn the fan on at
the set temperature and shall turn it off when the temperature is 2.5 degrees below the
set temperature.
9.1.9
Electronic Noise Suppression
The cabinet shall have sufficient electrical and electronic noise suppression to enable all
equipment in it to function properly. In addition, the cabinet shall be equipped with
one or more radio interference filters connected between the stages of the power line
surge protector. The filter(s) shall minimize interference generated in the cabinet in
both the broadcast and aircraft frequencies. The filter(s) shall provide attenuation of at
least 50 decibels over a frequency range of 200 kilohertz to 75 megahertz. Filters shall
be hermetically sealed in metal cases and shall be insulated. The filter shall be rated at
least at the rated current of the main circuit breaker, 125-volt, 60 Hertz.
9.1.10
Duplex Receptacle
The cabinet shall be equipped with a duplex receptacle located conveniently for service
personnel and in such a position that no electrical hazard will be presented to such
personnel when using the receptacle. The receptacle shall be of the 3-wire ground fault
interrupt type that will also accept a standard 2-prong, non-grounding plug. The
Section 9
Page 6 of 23
Control Equipment Cabinets
Charlotte Department of Transportation