As we said in one of our earlier installments, the I/O and terminal block categories are pretty quiet fronts--
as long as the parts work together.
A recent report from Venture Development Corp. (www.vdc-corp.com) surveyed users of distributed or remote I/O and named the most important features buyers were looking for. Quality/reliability, compatibility, ease of use, and data transfer rates were the top four product criteria, regardless of whether the user was using a distributed control system, PC-based control, or PLCs.
Price, customer support, and customer preference, in that order, were the top non-product or vendor criteria.
Below you'll find some of the latest and greatest in I/O, terminal blocks, signal conditioners, and intrinsic safety. More can be found in the installments that were web-published on September 9 and 16.
DeviceNet I/O Meets IP-67 Rating
DeviceNet I/O modules have onboard rotary addressing switches, network and sensor/actuator level LED diagnostics, and EMC, surge, and reverse-polarity protection. The fully potted, IP-67 I/O blocks have M12 connectors, are configured to handle 8-16 PNP or NPN inputs or eight outputs, and have an output rating of 2 A per port and 12 A per module. Connection to DeviceNet and the power supply is via Mini or M12 connectors.
Data Acquisition Devices
The PXI-4204 and PXI-4220 have integrated signal conditioning, seamlessly integrate with LabView 7 Express, and sample data at rates up to 200 kS/s. The PXI-4220 module is suitable for structural test and aerospace applications, including high-speed strain, load, and pressure measurements. The 100 V input range of the PXI-4204 module makes it suitable for high-voltage applications, such as 14 and 42 V automotive measurements.
Allen-Bradley IDC insulation displacement connection terminal blocks reduce installation time and conserve panel space. They save wiring time by eliminating the need to strip the wire insulation before termination. Wiring options include feed-through and ground blocks in two, three, and four termination versions for up to 14 AWG wires. Dual-level blocks allow two independent circuits to be terminated in the same panel width as a single terminal block, saving panel space.
R1MS eight-point thermocouple/DC input module is suitable for remote I/O and data acquisition applications. It has 1,500 VAC channel-to-channel isolation, noise filtering for 50/60 Hz, and each input channel has a transformer which can withstand 1,500 VAC between the channel and ground. It is available with PC Recorder software to trend, log, and analyze industry standard measurements.
Angled Terminal Blocks
With two levels and a width of 5.2 mm, the compact STTBS 2.5 terminal block with angled wire entrance is suitable when space is at a premium. Each level has two bridge channels that accommodate push-in style jumpers. It handles applications up to 300 V and 20 A and a wire range of 26-12 AWG. Styles include double-level feed-through, ground, double-level interconnected, and feed-through block for electrically neutral circuits.
Signal Conditioner Talks via Ethernet
The WV438 high-density, DIN rail-mount signal conditioner accepts a potentiometer input and provides a proportional, selectable DC output. It is field configurable via DIP switches for any three-wire potentiometer input 100-100k ohms. Outputs can be field-configured for DC signal ranges of 0-10 V, 0-20 mA, or 4-20 mA. With the WVC16 WebView communications interface, the input signal can be viewed over an Ethernet link.
Eurotherm Action Instruments
858/279-5726 www. actionio.com
NCS Net Concentrator distributed I/O network provides 20-bit measurement resolution, signal conditioning, and data rates up to 100 Mbaud. Using a 10/100BaseT Ethernet or Modbus RTU network, it connects transmitters, sensors, control valves, discrete devices, relays and other distributed field devices to a DCS, PLC, or PC. It handles current, voltage, millivolt, resistance, potentiometer, and discrete input signals, and provides current, voltage, discrete and relay control outputs.
Moore Industries Intl.
Surge Protectors Fit Foundation Fieldbus
MA15, FP32, and TP32 surge protectors operate without a voltage drop, causing negligible effects on a Foundation fieldbus system. The MA15 protects the power supply and prevents surges from entering the system via the AC main supply. The FP32 prevents surges occurring on the trunk or spurs from entering the control area or damaging terminators. The TP32 provides protection for field instruments. All meet IEC61158-2:2000.
Digital I/O Boards
The OMG-PCI-DIO series provide 24, 32, 48, and 96 channels of buffered digital I/O for PCIbus computers. Each board contains eight-bit I/O ports configurable as inputs or outputs. A user can customize the combination of inputs or outputs as needed, and the low order bit of the first port can be set to generate an interrupt for status monitoring applications. Windows and Linux drivers are included. Prices start at $159.