MTS 318 Load Unit - Manual (Page 20)

318 Load Unit 20 Introduction
LVDT
The LVDT measures the linear actuator’s travel. The LVDT consists of a
transformer with one primary and two secondary coils wound on a common
cylinder. The coil is stationary inside the actuator. A core is attached to the piston
rod of the actuator. As it moves inside the coil, it produces an electrical signal
that represents the position of the piston rod. The phase of the signal indicates the
direction the actuator rod is moving. An LVDT requires an AC conditioner to
process the signal.
Grip Controls The grip controls provide independent clamping control of the upper and lower
grips. The maximum pressure for the grip controls can be set up to 69 MPa
(10,000 psi). The pressure is factory set to 20 MPa (3000 psi); 45 MPa (6500
psi); or 69 MPa (10,000 psi) to accommodate a variety of grips manufactured by
MTS Systems Corporation. A front panel control allows the grip pressure to be
adjusted within the factory setting. A rate control sets how fast the grips open and
close.
318 Load Unit: Specifications
This section provides the specifications of the Series 318 Load Unit.
General specifications
The following table lists general specifications for the Series 318 Load Unit:
P ARAMETER S PECIFICATION
Load frame
Lifts
Locks
Grip control
Hydraulic (optional)
Hydraulic (optional)
Hydraulic (optional)
Service manifold
Maximum flow
Series 298 Actuator Manifold
114 L/min (30 gpm)
Axial actuator
Displacements
Series 244 Actuator
100 mm (4 in)
150 mm (6 in)
250 mm (10 in)
Accumulator Series 111 Accumulator