MTS Series 201 Actuators - Manual (Page 35)

Series 201 Actuator Operation
Series 201 Actuator Product Information 35
Operation
This section discusses the operation of the Series 201 Hydraulic Actuator and the
optional displacement transducer.
Series 201 Actuator Operation
Actuator piston rod movement is accomplished by supplying high-pressure
(21MPa [3000 psi] maximum) hydraulic fluid to one side of the actuator piston
and opening the other side to a return line. The pressure differential across the
piston forces the piston rod to move. The amount of hydraulic fluid and the speed
and direction of piston rod movement is controlled by a servovalve (For
additional information, refer to the servovalve Product Manual ).
When hydraulic pressure is applied to port A and port B is opened to the return
line, the piston rod extends from the actuator. When hydraulic pressure is applied
to port B and port A is opened to the return line, the piston rod retracts. The force
applied to a specimen attached between the actuator piston rod end and a reaction
mass is the product of the applied differential hydraulic pressure and the effective
piston area. For the effective piston area, refer to the specification tables .
Optional Displacement Transducer Operation
The internally mounted displacement transducer provides an indication of the
actuator piston rod displacement. The displacement transducer can be either an
LVDT (linear variable differential transformer) or Temposonics magnetostrictive
position sensor.
All displacement transducer adjustments are made at the factory. There are no
field adjustments.
Port A
Port B