CG-1280 Rev. N 09/13 - General Dynamics SATCOM Technologies

Overview2.4.2.8 Axis Overtravel Limit SwitchesOvertravel is prevented in each direction for each axis of rotation by electrical limitswitches with normally closed (open upon limit engagement) contacts. Theswitches are designed with double break contacts such that movement of theswitch actuator in either direction opens a corresponding set of discrete contacts.In this manner, only one limit switch assembly is required for each axis. Eachswitch is mounted with brackets, including adjustable strikers for each direction oftravel.2.4.2.9 Drive Cabinet Low-Temperature OptionThe standard 7200 ACS drive cabinet is rated to operate in an outside ambienttemperature range of 14° F (-10 °C) to 122° F (+50 °C). For systems where theambient temperature will fall below 14° F (-10 °C), an optional low-temperaturepackage is available for the drive cabinet.For the low-temperature option package, a 200 watt forced air convection heaterwith integrated fan and wall insulation are installed inside the drive cabinet. Overcurrent protection is provided by an individual circuit breaker sized to the wattageand input voltage of the heater. When the thermostat inside the drive cabinetregisters a temperature below 41°F (5°C), the heater is activated and heats the airinside the drive cabinet. An external thermostat shuts the heater off when outsideair exceeds 41°F (5°C). The heated air maintains the internal temperature of thedrive cabinet to within the standard operating temperature range.2.5 Controls and IndicatorsThe controls and indicators for the 7200 ACS are located on the ACU and insidethe drive cabinet. The EMERGENCY STOP button is located on the outside of thedrive cabinet and additional optional emergency stop switches may be provided atother locations.2.5.1 7200 ACU Controls and IndicatorsThe controls and indicators for the ACU are located on the front panel and on therear panel. The following sections describe the functions of the ACU controls andindicators.2.5.1.1 The Power On/Off SwitchThe power on/off switch is located on the rear of the 7200 ACU in the powerentry module. When the switch is set to the on position, power is applied to thepower supply in the ACU.2-21