Cleveland Motion Controls ULTRA ISC CANTILEVER TRANSDUCER CLTSCM REV AA - Manual (Page 20)

U LTRA S ERIES ISC C ANTILEVER T RANSDUCER T ECHNICAL M ANUAL MAN-70445-0 R EV AA
3 P RODUCT A PPLICATION
The Ultra Series ISC Cantilever Cell Transducer utilizes a twin sensing beam. Conversion from mechanical
strain to an electrical signal is accomplished using semiconductor-based, piezoresistive strain gage
elements. The Full Wheatstone Bridge configuration provides an electrically balanced output yielding twice
the amount of signal swing as half-bridged transducers operated at the same excitation voltage. Integral
span compensation is used to correct for temperature induced gain changes.
Ultra Series ISC Cantilever Cell Transducers can be mounted four different ways: Flange (FL), Stud (S), Pillow
Block (PB) and Bearing (BB) that incorporate their own low friction bearings.
Figure 7 shows these four mounting types. Refer to Section 4.2.2 for more information on Mounting
Configurations.
Although this figure represents mounting types for the Ultra Cantilever Transducer, the
same types of mounting configurations are also applicable to Ultra ISC Cantilever transducers..
TYPE "S"
MOUNTING
TYPE "PB"
MOUNTING
TYPE "FL"
MOUNTING
STATIONARY/DEAD SHAFT
SENSING ROLL
TYPE "BR"
MOUNTING
MACHINE FRAME MACHINE FRAME
STATIONARY/DEAD SHAFT STATIONARY/DEAD SHAFT STATIONARY/DEAD SHAFT
SENSING ROLL SENSING ROLL SENSING ROLL
Figure 7 Cantilever Cell Transducer Mounting Types
The Ultra ISC has been developed for those customers who desire to send the transducer signal directly into
their Controller, PLC, PAC, Drive, or Local I/O. It is responsibility of the customer to write this
software.
3.1 F INAL CALIBRATION
When calibration is done though application software within the target controller, the greatest calibration
accuracy is achieved though the use of individual gain and offset parameters for each of the two transducers
(which generally are used in pairs). By using separate analog inputs and separate gain and offset
parameters, you can correct for any transfer function differences arising from subtle mounting variations
intrinsic to transducer output variations. If however the load cells are summed first and then digitized, the
matching of load cell outputs (as affected by such things as load cell orientation relative to the wrap angle)
becomes more critical.
The tradeoff between hardware cost and accuracy will impact the decision as to which approach users
decide to take.
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