World's Smallest Fully Functional Isolated Analog Signal Conditioner Family Continues to Grow

In the 2+ years since Dataforth Corporation of Tucson, Arizona, introduced its miniature SensorLex® 8B isolated analog signal conditioners, the line has expanded to 17 family groups with a total of 102 different models. Originally developed in response to customer requests worldwide for a smaller, lower cost isolated signal conditioner, the SensorLex® 8B provides Instrument Class® performance in a miniature 1.11" x 1.65" x 0.4" (28.1mm x 41.9mm x 10.2mm) module.

The small size is ideal 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 virtually any other embedded industrial data acquisition system. With the SensorLex® 8B, it is 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 the 8B provides Instrument Class® analog output, it makes interfacing to almost any PC/104, CompactPCI, VMEbus, or proprietary data acquisition system board very easy.

Key 8B Features and Specifications Include:

• ±0.05% Accuracy
• ±0.02% Linearity
• 1500Vrms Isolation
• 3- to 5-Pole Low-Pass Filtering
• ANSI/IEEE C37.90.1 Transient Protection
• Field I/O Protection to 240VAC Continuous
• -40°C to +85°C Operating Temperature Range
• CE Compliant
• UL Listing Pending

8B modules interface to a wide variety of voltage, current, temperature, position, frequency, and strain measuring devices and are housed in a solidly potted thermoplastic plug-in-the-panel package. This industrial enclosure 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 mount configuration in the near future.

Modules that make up the SensorLex 8B family include voltage and current input modules; linearized 2-, 3-, and 4-wire RTD modules; potentiometer, strain gage, and both linearized and non-linearized thermocouple input modules; current and voltage output modules with 100Hz bandwidth; voltage input modules with 1kHz and 20kHz bandwidths; frequency input modules, and 2-wire transmitter interface modules.

Except for those models specified, signal bandwidth is 3Hz for most 8B modules. Output noise is as low as 250µVrms on the low bandwidth models. All modules have excellent stability over time and do not require recalibration.

Design-in 8B accessories include a selection of backpanels (2, 4, 8, and 16 channels) that provide screw-terminal inputs and outputs, as well as a DB25 header connector that connects 8B I/O to the user's data acquisition system. The DB25 cables are available in 1, 2, or 7 meter lengths. Moreover, a power supply module in the same 8B form-factor is offered to accommodate input voltages of 7 to 34VDC and provide 5VDC output at 2A to power any combination of 8B signal conditioners. The 8BPWR-2 module plugs into its own socket on the backpanel.

Analog signals the 8B can interface to include millivolt, volt, milliamp, thermocouple, RTD, potentiometer, slidewire, strain gage, frequency, and 2-wire transmitter. Analog output modules provide a wide selection of current and voltage output ranges.

Voltage input conditioners accept signals from ±10mV to ±60V, and current input conditioners accept signals of 0/4 to 20mA. Accepted thermocouple types are J, K, T, R, and S. Type Pt 100 RTDs can be 2-, 3-, or 4-wire. Potentiometer inputs can range from 0-100 ohms to 0-10k ohms. Strain gage transducers can have a resistance range of 100 ohms to 10k ohms, with sensitivities of 2mV/V, 3mV/V, or 10mV/V. Frequency input signals can be TTL or zero crossing with ranges from 0-500Hz to 0-100kHz. The 2-wire transmitter module provides loop power and accepts a 4 to 20mA 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 10V and ±10V.

Linearization of thermocouple signals is accomplished by a hardware implemented piece-wise approximation technique. The difference between sensor nonlinearity and the linearization provided by the 8B module is specified as conformity error. 8B modules use up to five segments to correct nonlinearity, which results in conformity errors as low as ±0.015% span. Cold junction compensation error for thermocouple inputs is ±0.5°C at 25°C ambient.

Each 8B module isolates the field-side input or output signal with an optical isolation barrier rated at 1500Vrms. Common-mode rejection is 120dB; by incorporating a 3-pole filter, normal-mode rejection is 70dB at 60Hz. In addition, field-side inputs or outputs are protected against accidental connection of line voltages up to 240VAC.

Operation and storage temperature is -40°C to +85°C, and relative humidity range is zero to 95% noncondensing. All models are CE Compliant and meet the requirements of EN61000-6-4 (radiated/conducted emissions) and EN61000-6-2 (ESD/RF/EFT immunity). For operation in hazardous environments, North American Class I, Division 2, and European Group II, Category 3, approvals are pending.

Dataforth Corporation was established in 1984 and is a worldwide leader in the design and manufacture of signal conditioning, data acquisition, and data communication products for industrial and institutional markets. The company is ISO9001:2015 registered and offers a broad range of analog and digital I/O modules, 2-wire transmitters, data acquisition systems, industrial data modems, and modem systems.

For additional information and pricing, call 800-444-7644 toll-free, or e-mail at sales@dataforth.com.

Original release: September, 2007