Owner's manual

Series 322 Load Unit

Introduction

Force The force transducer (also called load cell or force sensor) measures the amount

of tension or compression and rotational torque applied to it. It has four strain

gages that form a balanced Wheatstone bridge. When forces are applied to the

bridge, it becomes unbalanced and produces an electrical signal that is

proportional to the force applied to it. The force transducer is a resistive device

and requires a DC conditioner to process the axial signal from the Wheatstone

bridge.

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.