With ordinary care and attention to the operating instructions, the only elements that may require periodic inspection and maintenance are the brushes. Their replacement is infrequently needed because they are made of a special carbon and are of a design that assures proper contact of the brush to the commutator at any setting.
LOW OPERATING TORQUE
The glass-smooth commutator surface, the constant and correct contact pressure of the brush-tap to the commutator and the stable positioning of coif and internal components result in the low operating torque of all POWERSTAT Variable Transformers. The driving torque for the individual units is given in the section devoted to the particular type.
LINEAR OUTPUT VOLTAGE
The angle of rotation from zero to maximum output voltage is given for each POWERSTAT Variable Transformer In the section devoted to the particular series, Output voltage is continuously adjustable from zero to maximum output voltage proportionately over the full range.
The output voltage of a POWERSTAT Variable Transformer can be considered continuously adjustable. The voltage between turns is a fraction of a volt and the brush-tap is always in contact with one or more turns of the winding. Adjustment of output voltage can be made to a fraction of a volt.
RUGGED MECHANICAL CONSTRUCTION
All POWERSTAT Variable Transformers are designed for heavy duty, trouble-free operation. Rigid Inspection at every stage of manufacture gives assurance of a quality-built product. The securely mounted core and coil, extra large aluminum brush heat radiator and durable brush assembly reduce the need for attention or replacement.
POWERSTAT Variable Transformers give reliable performance over extended periods of time even under extreme operating conditions. Materials are constantly being improved to give increased life expectancy.
All POWERSTAT Variable Transformer models are available on special order to meet applicable military specifications. The following are typical of the requirements which can be met:
ALTITUDE: Up to 10,000 feet operating; 50,000 feet non-operating
HUMIDITY: '95 per cent relative humidity for 24 hours
VIBRATION: Per MIL-ST0-810C, Method 514.2
SHOCK: Per Mll:STD-810C. Method 516.2
CORROSION· All metal parts except the commutator protected to withstand 100-hour salt spray per FED-STD-151A
PHENOLIC PARTS: Laminater parts per MIL-P-15035C; molded parts per MIL-M 14F: rods and tubes per Mll-P-79C; and anti-fungus treatment per MIL·T-1528. Type 2.
CONNECTING WIRE: Per Mll·W-16878D