In June of this year, we asked the Control Design audience about their preferences when they choose terminal blocks and other I/O modules. Here are a few of the findings.
In terms of the signal types that these terminal blocks and I/O support, a mix of analog and digital I/O was prevalent with a continuing bias toward digital. Some 62% reported mostly digital with some analog, while 22% report a mix of both. About 8 % reported using digital I/O only, and 7 % indicated mostly analog with some digital. Only 1% reported an exclusive reliance on analog I/O.
SEE ALSO: What's an I/O Device?
By comparison, in 2010, 53% reported mostly digital with some analog, with 27% reporting a mix of both, and those using mostly analog was 14%.
Survey respondents that used remote I/O further indicated that 72% of it was in-cabinet mounted, 14% was IP67-rated machine mount, and 11% IP20-rated machine mount. It appears that the bandwagon jump to machine-mount I/O is hardly a mob action. In 2010, survey respondents that used some remote said 69% of it was cabinet mount, 14% was IP67 machine mount, and 8% was IP20 machine mount, so not much change at all.
Finally, the respondents told us that the physical cable connection technique they most preferred was screw clamps (49%), followed by spring clamps (33%), M8/M12 terminal (13%) and IDC (4%).
I/O Supports PoE
Connect digital and analog I/O to your network with eI/O 170E; it has eight 12-bit analog inputs, two optically isolated digital inputs, and two solid-state relay outputs for monitoring and control applications. All are DIN-rail-mount-compatible, and PoE and dc input models are available.
Like it Hot
Special industrial temperature electronic components in the X20 and X67 control and I/O system modules enable operating temperature range of -25 to 60 °C; modules can be stored at -40 to 85 °C. Special CompactFlash cards withstand these extreme temperatures.
B&R Industrial Automation
2007 Series Topjob S current transformer disconnect terminal blocks with Cage Clamp S spring-pressure technology for conductor sizes 20–8 AWG have an intuitive orange three-position (operating, shorting and measuring) disconnect lever. Touch-proof design does not require a separate cover. Four marking locations help ensure wiring accuracy: on the disconnect link, on top of the terminal block and on the sides. Marking is provided via WMB marker tags or a continuous marking strip.
Adam-6266 is a four-channel relay output Modbus TCP with four digital input channels. There are 2 x RJ45 Ethernet ports for daisy-chain connection, Graphic Condition Logic for local and distributed control, user-configurable HTML5 web page, and a free utility and .NET class library.
Advantech Industrial Automation
Industrial Ethernet Multiprotocol technology for distributed I/O is designed to operate across all company’s distributed I/O product families in any application that uses a host system with Modbus TCP/IP (client), EtherNet/IP (scanner) or Profinet (master). On network power-up, the device will recognize the network protocol available to the network.
Support the Lower Levels
BusWorks XTA-120V-6 optocoupler modules have six individually isolated 120 Vac/dc digital (discrete) inputs to sense on/off levels, and provide 5-32 Vdc logic outputs to a fieldbus input module or controller. XTA-MRNO-6 interposing relay module receives 4-32 Vdc logic-level signals from an output module or controller to switch six mechanical relay outputs. These high-voltage relay interface modules monitor or control inductive and other high-power loads with control system input/output modules that only support low-level dc signals.
XI or XN
XI/ON modular I/O system includes XN series with hot-swappable plug-in modules, and XNE series provides integrated I/O modules and bases in higher-density configurations. Base modules for the XN Series connect field wiring for standard XI/ON modules; they’re available for two, three and four-wire connections, as block or slice modules, with spring-cage or screw terminals. XNE modules have push-in, spring-cage terminals only and are compatible with XN spring-cage base modules. Standard fieldbuses include EtherNet/IP, Modbus TCP, DeviceNet, Profibus-DP, and CANopen.
EP9214 power distributor box enables local distribution and switching off of the power supply, providing the ability to supply up to four NEC class-2 circuits via M8 plug connectors. The I/O solution also provides diagnostics and control functionality for up to eight 24 Vdc branch circuits (Us & Up power) per power box. Equipped with 7/8-inch plug connectors, it maintains a total current of 16 A for each control and peripheral voltage with cable cross-sections of 1.5 and 2.5 mm2 (roughly #14AWG).
Blocks in Tiers
PRV terminals consist of four-, eight- and 16-tier marshalling distribution terminals; the 16-way multi-tier terminal block (64 connections per terminal) can distribute more than 1,700 signals per 39 inches of DIN-rail space. PPV terminals comprise the four- and eight-tier power distribution terminals. Both incorporate “push in” connection technology and the PPV/PRV 4/8/16 terminals carry 300 V/10 A/26-16 AWG electrical ratings, and UL and CSA approvals.
G11 AS-Interface I/O modules include two analog outputs each—one for 0–20 mA operation for flat-cable connectivity and one for 0–20 mA with an M12 round connector. A third module has four analog outputs of either 0–20 mA or 0–10 V for flat cable connectivity powered by AS-Interface or an auxiliary power source. The output type of each module can be selected by DIP switch.
Brought to Tiers
Konnect-It single-level terminal blocks handle currents to 175 A, wiring sizes 26 to 2/0 AWG and have a 100 kA SCCR rating. Double-level terminal blocks come in 20 A and 30 A versions and a variety of colors. Options include LED indicators, diode and direct cross level connections, and an added grounding leg. Triple-level terminal blocks handle up to 24 A and wire sizes 24 to 12 AWG. Optional features include NPN and PNP sensor blocks with LED indication and added grounding leg.
Power on Top
PTIO 1.5/S push-in technology terminal blocks have a new top-level location for the power wiring, and are available in three-wire and four-wire versions. The upper level is for signal feed-through, and is available with or without an LED. Continuous bridge shafts allow a quick and simple potential distribution of power using push-in bridges. It has five times the IEC requirement for retention force.
Keep Your Polarity Straight
Cube20S connects 12.9-mm two, four, or eight-channel input and output modules and function modules to base modules with integrated bus nodes. Up to 64 modules can be connected to each bus node with minimal wiring. The backplane’s push-plug mechanism protects modules from reverse polarity. The bases feature a special locking system for DIN-rail mounting, which makes it possible to assemble the complete station outside the control cabinet and then mount it in as a finished block.
1492-JP process terminal blocks are designed to improve the way signal routing and distribution are performed. The blocks provide an integrated shielding connection in feed-through and fuse terminal blocks, removing the need for an additional grounding terminal block. Disconnect terminal blocks are available for maintenance and troubleshooting purposes. These terminal blocks accept a component plug, disconnect plug or fuse plug.
Secure the Connection
ASIUDT NEMA series single-level, feed-through terminal block accepts a crimped ring terminal to eliminate concern of connection security. A snap-on feature is employed for installation of the smaller sizes and slide-on technology assures secure installation of the larger sizes. Models are UL-approved, 10–309 A and 600 V.
Prepare Your Looms
NX-Series I/O provides from two to 16 digital input or output points. Analog I/O is available with two to eight signals per unit for current, voltage, thermocouple or RTD signals. All I/O units have the same height and depth (100x71 mm), and have a detachable front connector with push-in type screwless terminals. I/O wiring looms can be prepared and installed separately, signals can be disconnected for testing and commissioning, and units can be replaced without re-wiring.
Omron Automation and Safety
Keep Old I/O
G4EB2 I/O processor integrates an existing, legacy Pamux G4 digital I/O system with modern Snap PAC controllers and PAC Project software over Ethernet without changing existing I/O or field wiring. G4EB2 directly replaces a 32-channel digital I/O processor in a legacy Pamux system.
Siplus Extreme ET200SP distributed I/O system operates in a range of -40 to 70 °C. It’s resistant to harmful gases including chemical, biological, salt spray and mechanically active substances, is protected against condensation, and operates in elevations from -1,000 to 5,000 m.
Brad HarshIO Profinet I/O modules are PNO-certified to meet Profinet specifications for conformance class B. Fast Start-Up (FSU) technology connects industrial controllers to I/O devices, and Simple Network Management Protocol (SNMP) support extends module diagnostics of network functions, such as port status messages. Media Redundancy Protocol (MRP) increases data reliability.
ST Series modular distributed I/O system operates as a slave device station for CC-Link or Profibus device-level networks. It includes a head unit, power supply and DIN rail to form a remote system, or node, and has a scalable architecture that accepts mix-and-match I/O configurations and I/O concentrations from two to 16 I/O points.
Mitsubishi Electric Automation
Local or Remote
Family of I/O products can be used as local I/O with company’s controllers or as a standalone Ethernet Remote I/O with any system that communicates via ModbusTCP. The SM-CIO100806 provides 10 24 Vdc digital inputs, eight 2 A digital outputs, and six analog inputs. All loops can be powered by the I/O board, if desired. The analog inputs are 15-bit resolution, and support two-, three- or four-wire transmitters. Digital outputs use solid state relays.
LioN-M I/O EtherNet/IP modules have 16 digital I/O channels with universal input/output functionality for direct connections between sensors/actuators and control systems. The universal modules (16DIO universal) provide 16 digital inputs and 16 digital outputs in any desired combination without individual parameterization.
microNCS provides Modbus RTU (RS-485) master capabilities, cost-effective distributed data acquisition and, with expansion I/O, control capabilities. One or both of the microNCS’s Modbus RTU ports can be configured to poll other RTU slaves with all of the network polling functions of a typical Modbus master. An industry-standard OPC interface delivers plug-and-play integration with popular PC-based HMI and SCADA software packages.
Connect at the Sumit
PXM-UIO96-2 96-line digital I/O module offers PCI Express expansion on a PC/104-sized module enabled by a stackable high-speed Sumit connector. It uses a Lattice Semiconductor FPGA with a superset of the company’s universal I/O controller cores. Each I/O line is programmable for input, output or output with read-back operation.
Fuse the Circuit
WTB2-FB130L IEC fuse holder terminal blocks have a current rating to 30 A, and accept ¼- x 1¼-inch fuses. They have a built-in LED circuit to indicate when the fuse blows and funneled wiring entry with finger-safe IP20 terminals. Its marking system allows for fast and easy circuit identification.
The Ins and Outs
SureCross B2Q gateway module for Q45 wireless sensor network has discrete outputs and DIP switches to map inputs from up to two wireless sensors to the gateway’s outputs. Site Survey analyzes network strength and reliability, and conveys results through a bi-color LED; DIP switches have eight defined I/O mapping configurations to automatically map inputs to the outputs. Transceivers provide bidirectional communication between the gateway and device.
Four-channel IO-Link Master equipped with M12 connectors provides EtherNet/IP and Modbus TCP access to IO-Link sensor process, event and service data with Class 1 (implicit) and Class 3 (explicit) interfaces, write-to-Tag/File, read-from-Tag/File, LEDs for device, network and port status, and IO-Link COM1, COM2 and COM3 support at 230K baud rate.
Save Wiring Time
Interfast PLC pre-wiring system can reduce wiring time up to 98% by eliminating the need to wire each point from the input of the PLC to field wires individually, and cable strands can be readily identified inside the control cabinet. Use the configurator from a desktop; no Internet connection is required to determine the connection configuration.
Distributed and Modular
Distributed modular I/O with IP67 protection and industry-standard connectors uses standard three-conductor cables. Up to four slave devices can be connected to each master block, which communicates via industrial Ethernet to the controller. With point-to-point IO-Link, the system is fieldbus-independent and vendor-neutral.