MTS Landmark Tabletop - Manual (Page 68)

Hydraulic Power Off
Hydraulic Power is prevented from energizing the circuit via the hydraulic service manifold. Full access to the
test area is allowed in this mode.
Specimen Installation and Setup
The controller provides a means for creating a specimen installation mode. This mode typically uses the
Channel Limited Channel (CLC) control method. The primary control channel is Displacement (stroke) with
maximum limits set on applied force. Tuning parameters unique to this mode optimize manual control during
this mode. In addition, a maximum velocity command is set.
The handset has the ability to have a configuration specific desired response to the thumbwheel encoder on
the handset for a precise level of control.
In conjunction with the controller and specimen installation mode using the handset, the load frame itself has
two operation modes: full flow, and actuator velocity limiting restricted flow. A switch on the load frame control
panel activates a solenoid which controls a hydraulic circuit within the load frame hydraulic service manifold.
In the actuator velocity limiting mode, oil flow to the actuator is directed through an orifice which limits actuator
velocity to 10 mm/second or less. This switch circuit is integrated with the test area enclosure door switches.
The enclosure has doors on the front and rear of the test area which are locked and confirmed secure with
a keyed latch mechanism. Power must be applied to the door switches to allow entry into the test area. Power
is applied to the door switches when the system is in the actuator velocity limiting mode. When either of the
doors is open, the system will not permit the operator to return the load frame into full flow mode or put the
controller in program run mode. If the solenoid door latch is defeated and the door is opened during normal
operation, the system will detect this and activate the limited actuator velocity mode and put the controller
into program interlock mode.
Specimen Installation and Setup–Interrupt Operation
To interrupt operation:
1. Switch the system to the CLC manual control mode.
2. Activate the handset control.
3. Prior to gaining access to the test area, switch to velocity limiting mode on the load frame control panel.
Specimen setup or removal can now take place inside the test area enclosure.
Specimen Installation and Setup–Resume Operation
To resume normal test mode:
1. Close the door.
2. Switch to full flow mode.
3. Deselect the handset control.
4. Put the system into the control mode desired for the start of the test.
68 MTS Landmark™ Tabletop Load Units Product Information
Operation