The IL78A Conditioner is a stable, high-accuracy single-channel AC Strain gage conditioner of phase-sensitive carrier-amplifier design.
The IL78A delivers filtered analog output of ±5, ±10 VDC or 4-20 ma or 4-12-20 mA. The IL78A advanced analog design directly addresses the problem of measurement inaccuracy in industrial environments of high electromechanical noise. Exceptional signal stability and accuracy over a remarkably wide range of sensor inputs are achieved through:
• regulated, remotely sensed AC excitation
• precise symmetry and signal phase adjustment
• selectable low-pass active filtering
• wide range zero and span controls
• internal shunt resistor provided
While intended primarily for applications involving transformer-coupling to the transducer bridge (as with conventional rotary-transformer torque sensors), the Model IL78A can also be used when high sensitivity is required or where the electrical environment is especially noisy. Responding only to the modulated carrier frequency, the IL78A rejects extraneous voltages that can cause errors in DC systems, particularly when there is a need to “blow up” a portion of the transducer range.
THE IL78A OVERCOMES ERRORS THAT TRADITIONALLY PLAGUE THE STRAIN-GAGE MEASUREMENT PROCESS
For steady indication and smooth, dependable control action, the IL78A can provide a true average value of the measured variable, even in the face of substantial dynamic content. Model feature are:
• Wide zero and span controls compatible with a wide range of rotary torque transducer and sensor manufacturers.
• Powerful low-pass active filtering - selectable via internal panel switch settings for removal of unwanted high-frequency measurement-signal components and the elimination of aliasing errors, if the module’s output is subsequently sampled.
• Internal 59k Ohm shunt resistor is provided for applications that require calibration or systems checkout when a dead weight method is not available or practical.
• Phase and symmetry controls used to synchronize phase shifts due to sensor and cabling capacitance characteristics. Symmetry used to compensate sensors with non-symmetrical CW or CCW span. • Remote sensed excitation provides automatic excitation compensation control for installations which require long transducer interface cables.