MTS Material Test Systems - Manual (Page 42)

Actuators
After checking the electrical and hydraulic power unit connections, the actuator position control electronics
(the Set Point control on the selected controller) should be checked for signal polarity and control. This is
accomplished by performing the following steps:
1. Clear the area around the piston rod of obstructions.
2. Select the desired control mode (typically load).
3. Clear any active interlocks.
4. Apply hydraulic pressure by completing the following steps:
a. Press the Hydraulic Pressure Low switch to start the HPU and apply low hydraulic pressure to the
actuator (the Off indicator will extinguish and the Low indicator will light).
b. Observe the actuator for any movement caused by hydraulic fluid pressurizing the system. Ensure that
the actuator stabilizes before proceeding.
c. Press the Hydraulic Pressure High switch to apply high hydraulic pressure to the actuator (the Low
indicator will extinguish and the High indicator will light).
5. Slowly adjust the Set Point control on the controller and observe piston movement. The direction and
response should be appropriate for the system configuration. The system phase can be determined as
follows:
• If the Set Point control is adjusted in a negative direction and the actuator retracts, then the system
is set for a positive phase.
• If the Set Point control is adjusted in a negative direction and the actuator extends, then the system
is set for a negative phase.
42 MTS Material Test System Operation
5.0 Installation Guidelines