By Patti pool, new products editor
We need signal conditioners to ensure that sensor accuracy, transmission and signal type are compatible with the rest of the control system. Signal conditioners are the workhorses in control systems that enable system accuracies that cant be achieved in any other way. For instance, they perform conversion, isolation, amplification, filtering and linearization of analog sensor signals.
So, how do we make signal conditioners simple to use? One avenue to take is plug-and-play, commonly known as a transducer electronic data sheet (TEDS). Standard P1451.4 is the most recent addition to IEEEs family of smart transducer interface standards. P1451.4 provides a relatively simple mechanism for building plug-and-play into traditional analog sensors.
The standard specifies the format and content of self-identifying parameters stored in the TEDs. The standard also defines two mixed-mode interfaces, analog and digital, that will enable various types of automatic sensing systems to access the sensors self-identification data.
A number of manufacturers have included P1451.4-compliant TEDS on their sensors for several years. Sensor data are thus electronically available for interrogation, and signal conditioners have been adapted to do that interrogation.
Plug-and-play eliminates the need to read and enter data from a paper calibration sheet. The calibration sheet stays with the sensor.
Theres also no cable confusion. Plug-and-play technology enables the signal conditioner to read a sensors type and calibration information, as well as tell you exactly where your sensor is located.
With a TEDS sensor that automatically provides calibration data to an active signal conditioner, a technician unfamiliar with calibration procedures can swap a sensor quickly without hurting the integrity of the system operation.
Burning location data onto each sensors TEDS will help you to inventory your sensorsgreat for large installations where looking for the right sensor could be a headache.
Plug-and-play implemented according to P1451.4 makes plugging sensors from one manufacturer into signal conditioners from another much easier for the end user.
Enhanced version of the SCM5B48 isolated and field-configurable accelerometer input signal conditioning module provides excitation to piezoelectric sensors with built-in microelectronic amplifiers, commonly known as ICP, IEPE or LIVM sensors. The module provides a constant current excitation to the sensor and then isolates, filters and amplifies the sensor output, yielding a high-level analog voltage output. The excitation current, signal gain and filter high-pass and low-pass cutoff frequencies are field-configurable through a set of switches. Dataforth; 520/741-1404; dataforth.com
Model LVDT-8A signal conditioner board offers eight channels of signal conditioning on one board, providing enhanced capability of simultaneous outputs that directly correspond to the sensed positions in a real-time environment. Use the board in factory automation environments such as machining, inspection, automotive and weighing.
Acces I/O Products; 858/550-9559; accesio.com
MSXB 078 digital I/O expansion hardware combines simultaneous operation on all channels with an isolated ground to protect your application ground currents. It provides 16 digital inputs and 16 digital outputs on an HD62 connector, with headers for alternate connectors. Eight MSXB 078 boards connected to a single DAP board provide 128 digital inputs and 128 digital outputsall operating simultaneously and with a ground isolated from the PC.
Microstar Laboratories; 425/453-2345; mstarlabs.com
K-System modular components provide signal transfer protection between field devices and control systems and conform to SIL ratings. High-density, intrinsically-safe isolators for hazardous areas, signal conditioners for non-hazardous areas, limit alarms and logic controls come in one housing style, and keyed removable terminals ensure proper connection. Modules mount in any orientation to panels, DIN rails, motherboards, or to this companys PowerRail.
Pepperl+Fuchs; 330/486-0002; am.pepperl-fuchs.com
JumpFlex Series 857 6-mm-wide, DIN-rail mount signal conditioning and relay modules include 12 different typesboth configurable and dedicated. Signal types supported include current, voltage, HART protocol, RTDs and thermocouples. Configurations include splitter, single and multi-channel, repeater, and loop-powered modules. Configurable modules are programmed via dipswitch (for current, voltage and temperature) and/or FDT/DTM software (temperature only). They have pre-marked modules for easy circuit identification, marking tag holder for module identification and built-in indication for power or signal status.
Wago; 262/255-6222; wago.us