Exclusive: Dataforth introduces 1/5th-size, isolated analog signal conditioner

Tucson, AZ—Dataforth Corp. recently introduced its new SensorLex 8B miniature, isolated analog signal conditioners, which reportedly provide its Instrument Class performance in a package that is 20% of the size of competing modular products.

By Control Engineering Staff December 7, 2004

Tucson, AZ— Dataforth Corp. recently introduced its new SensorLex 8B miniature, isolated analog signal conditioners, which reportedly provide its Instrument Class performance in a package that is 20% of the size of competing modular products. The company says 8B’s small size is ideally suited for embedded or portable applications, such as mobile test stands, COTS military and defense applications, miniaturized security and surveillance systems, embedded process controls for semiconductor manufacturing equipment, and any other embedded industrial data acquisition system.

8B makes it possible to incorporate high-performance modular I/O on a per-channel basis for any embedded monitoring or measurement and control system. In addition, because it provides an Instrument Class analog output, it eases interfacing to almost any PC/104, CompactPCI, VMEbus, or proprietary data acquisition system board.

8B consists of 15 family groups with a total of 95 models, which interface with a variety of voltage, current, temperature, position, frequency, and strain measuring devices. Housed in a solidly potted thermoplastic plug-in-the-panel package measuring only 1.11 x 1.65 x 0.4 in. (28.1 x 41.9 x 10.2mm), 8B’s industrial enclosure reportedly provides excellent impact properties, dimensional stability over temperature, chemical resistance, and a flammability rating of UL-94 V-0. The line will also be available in a DIN rail-mount configuration in the near future.

Design-in accessories include backpanels, with 2, 4, 8 and 16 channels, that provide screw-terminal inputs and outputs, as well as a DB25 header connector. The DB25 header can be matched with a 1-, 2-, or 7-meter cable to connect sensors and transducers to an external 25-screw-terminal interface board. Also, a power supply module in the same 8B form factor is offered to accommodate input voltages of 12 to 36 V dc and provide 5 V dc output at 2 A to power any combination of 8B signal conditioners. The 8BPWR module plugs into its own socket on the backpanel, which protects the power supply module from transients and reverse wiring errors.

8B’s Instrument Class performance specifications include

Signal interfaces, other models In addition, 8B can interface to many analog signals, including millivolt, volt, milliamp, thermocouple (linearized and nonlinearized), RTD, potentiometer, slidewire, strain gage, frequency, and two-wire transmitter. Available analog output modules provide a selection of cur-rent and voltage output ranges.

Voltage input conditioners accept signals fromhms to 10 k ohms, with sensitivities of 2 mV/V, 3 mV/V, or 10 mV/V. Frequency input signals can be TTL or zero crossing with ranges from 0-500 Hz to 0-100 kHz. The two-wire transmitter module provides loop power and accepts a 4 to 20 mA input signal.

Additional models offer isolated field-side current and voltage outputs. Current output ranges are 0 to 20 and 4 to 20 milliamp, while voltage output ranges are 0 to 10 V and +/-10 V. Accuracy rating is

Linearization of thermocouple signals is accomplished by a hardware-implemented, piece-wise approximation technique. The difference between sensor nonlinearity and the 8B’s linearization is specified as conformity error. 8B modules use up to five segments to correct nonlinearity, which results in conformity errors as low as

Also, signal bandwidth is 3Hz for most models, with exceptions being 100 Hz for current output modules and 20kHz for high-bandwidth voltage input modules. Output noise is as low as 250

Each 8B module isolates the field-side input or output signal with an optical isolation barrier rated at 1500 Vrms. Common-mode rejection is 120dB; by incorporating a three-pole filter, normal-mode rejection is 70dB at 60Hz. Also, field-side inputs or outputs are protected against accidental connection of line voltages up to 240 V ac.

Control Engineering Daily News DeskJim Montague, news editorjmontague@reedbusiness.com