Terminal blocks and I/O go digital

Oct. 28, 2014
How these innovative devices can help slash machine builders' costs.

In June, we surveyed a portion of Control Design's audience to identify important application trends they see in I/O modules and terminal block technologies, as well as determine the usage of these devices.

In terms of the signal types that these terminal blocks and I/O support, the move to digital is an ongoing trend. About 50% of the respondents reported using mostly digital with some analog. Some 27% report using about half-and-half as compared to 2013, when this number weighed in at 22%. About 9% said they use digital I/O only, up a bit from last year's 8%. Only about 3% reported relying exclusively on analog I/O.

More, More, More

Find more I/O and terminal block products from companies including AMK, Comtrol, SoftPLC and WinSystems at

Nearly 39% of the respondents reported using a centralized I/O system, with some remote; while one-third said their I/O was mainly remote/distributed, with some centralized. Respondents that used remote I/O further indicated that about 63% of it was in-cabinet-mounted; 21% was IP67-rated machine mount; and 14% was IP20-rated machine mount.

Also Read: Think Global I/O, Connect (Sometimes) Local

Lastly, the respondents told us that the physical cable connection technology they most preferred was screw clamps (52%), followed by spring clamps (25%), M8/M12 terminal (19%) and IDC (4%).

Screwless Terminal Blocks
SNK PI-Spring terminal blocks have self-guiding wire entries that allow direct, one-step, push-in insertions with solid wires and stranded wires with ferrules. The terminal blocks let users insert stranded wire by using a screwdriver to open the spring clamp.  

Compact I/O Modules    
BusWorks XT Ethernet remote I/O modules interface discrete and analog I/O directly to a measurement and control network using Ethernet/IP, Modbus/TCP, Profinet or i2o peer-to-peer protocols. Modules have dual Ethernet ports, removable front-facing terminal blocks and DIN-rail, power-bus support. A USB port provides an easy connection to a PC for fast configuration and setup with free Windows software. The modules operate -40 to 70 °C, have noise immunity, surge protection and CE compliance.

Ethernet I/O Modules with Smarts
Adam-6200 Series Ethernet-based remote I/O modules provide distributed control capabilities with peer-to-peer communication and graphic condition logic programmability for programmable control in the module or between modules. Peer-to-peer communication is enhanced with a switch and two RJ-45 10/100 Ethernet ports in each module, supporting daisy-chain connectivity. The internal switch has a physical auto-bypass feature that ensures continuity of the network should the module fail.
Plug Them In    
Pluggable relay terminal blocks include ASIPLCREL24VACDC, a 6-mm wide relay base equipped with a SPDT relay rated at 6 A, 250 Vac with a coil voltage of 24 Vac/dc. ASIUDK-PLC-RII24VDC is a 14-mm wide relay base equipped with a DPDT relay rated at 6 A, 250 Vac with a coil voltage of 24 Vdc. The base snaps on to the industry-standard DIN rail. Connections are made with screw clamp wire terminations, and an actuator serves to lock the relay in place and eject it for easy removal. The relay base has a LED for visual indication of operation.
Jumpers and Cutters
DINnectors terminal block accessories include jumpers used to electrically connect two or more consecutive terminal blocks without reducing the wire capacity of the blocks. The jumpers are available in two, three, four and longer pole configurations. They are made of electrolytic copper with a corrosion-resistant nickel plating. Jumper cutting tools maintain jumper protective coverings. A special cutting tool kit with one handle and five dies is available.
Gateway Coupler    
EK9300 Profinet I/O bus coupler allows a Profinet controller to exchange data with one or more EtherCAT, Profinet, Profibus and, in the future, EtherNet/IP systems. The device supports collecting product data in distributed units with different control systems and supports the exchange of data in real time between two Profinet networks in different IP spaces.
Beckhoff Automation;
Intelligent Master Modules
X20DS438A with IP20 protection and the X67DS438A with IP67 protection are master modules that use IO-Link 1.1 to communicate digitally with four intelligent field devices such as sensors and actuators. The bidirectional digital communication interface exchanges parameter data and diagnostic information to intelligently integrate sensors and switching devices into the control level. IO-Link complements industrial, real-time Ethernet Powerlink.
B&R Industrial Automation;

Cold Junction Compensation
MAQ20 thermocouple input modules have eight differential input channels, which are grouped into four blocks of two channels. Each block has a terminal for sensor shield ground and a dedicated ambient temperature sensor optimally positioned to accurately measure the terminal block temperature in any system configuration, any module orientation and over the operating range of -40 to 85 °C.  
Granular I/O    
PACSystems RSTi is a standards-based granular machine I/O integrated with the company's PACSystems controllers on Profinet, providing a communication link between field I/O and controller. More than 80 different module types are available for discrete, process, motion and specialty applications.
GE Intelligent Platforms;

Modules For Harsh Environments
Brad HarshIO IP67 Ethernet modules are machine-mountable for connecting industrial controllers to I/O devices in harsh-duty environments. The units have 30-mm housings suitable for compact machines where space is limited. I/O channels can be individually configured as inputs or outputs with M8 or M12 connectors for attaching sensing devices or actuators.

Single or Dual
NET Concentrator System (NCS) process control and distributed I/O network comes with an Ethernet (Modbus/TCP) port and dual, independent Modbus RTU (RS-485) ports. The Modbus RTU ports can be configured as Modbus master ports, allowing the NCS to poll other Modbus RTU slaves with the network polling functions of a typical Modbus master. It can be used as a single or dual Modbus master, letting it provide simultaneous Ethernet and dual Modbus RTU master/slave communications.
Moore Industries-Int'l;

Slice of Motion    
NX-Series EtherCAT coupler and slice I/O uses the distributed clock function of the EtherCAT machine network to obtain high-speed, deterministic control. The NX-Series I/O synchronizes with the controller's primary task cycle, so logic motion, safety, vision and I/O can be updated without affecting the control cycle. Digital I/O units range from two to 16 input or output points in 12-mm widths. A full range of analog I/O is available, with two to eight signals per unit, for current, voltage, thermocouple or RTD signals. High-performance models provide 10 µs conversion time per channel and 1:30,000 resolution.
Omron Automation and Safety;

Two For One    
VBA-2A-G10-E2L-1M-2V1-W AS-Interface module provides two outputs. Each output is completely powered by an auxiliary, black, flat cable to deliver up to 2 A per output and up to 4 A per module.

Miniature Blocks
MPT mini-terminal blocks with push-in technology fit on NS 15 DIN rails, and can be used in smaller control boxes. A universal test point supports standardized test accessories independent of bridging, while multiple marker locations identify termination points.
Phoenix Contact;

Small Space, Lots of Functions
Allen-Bradley 1492-JP process terminal blocks have a space-saving, multifunctional design. They tout a 45% space savings per signal loop, compared to traditional feed-through, fuse and grounding terminal blocks, while maintaining similar voltage and current ratings and an integrated shielding connection in feed-through and fuse terminal blocks, removing the need for an additional grounding terminal block. They offer double-hinged fuse blocks for disconnect capability, blown-fuse indication with low leakage-current rating, and three-channel center jumpering capability.
Rockwell Automation;

Compact, Distributed I/O
Simatic ET 200AL compact distributed I/O provides IP67 protection and mounts in small and moving spaces such as assembly lines. The module is 30- or 45-mm wide, with front or diagonal screw-mounting options. It can be installed in any position, directly in a machine or on mounting rails using M8 sensor connections. It provides electronic short-circuit protection, and restarts automatically after a line interruption or module exchange.
Siemens Industry;

Speaks Many Languages
FEN20 in-cabinet I/O station automatically recognizes EtherNet/IPTM, Profinet or Modbus TCPTM protocols on power-up. The unit is available with 16 configurable I/Os, power isolation between I/O zones and an embedded Ethernet switch. The station can be addressed via an external rotary switch or a web server, and supports DHCP and LLDP.

Terminal Blocks Wire Easily
Topjobs rail-mount terminal blocks use company's spring-pressure-connections, which allow direct push-in when using solid or ferruled wires. A locking tab and screwdriver actuation lets users remove stranded wires. The terminal blocks feature multiple options including two-, three- and four-conductor feed-through configurations, and multi-level, angled entry, ground and disconnects. They are rated to 600 V, 85 A, UL/CSA and 22-4 AWG.
Remote I/O System
U-remote compact, advanced IP20 system has hot-swappable slices, an integrated self-configuring web server interface and simple plug-in connections. High-density remote I/O modules have individual channel diagnostics. The modules provide 32 connection points on a single 11.5-mm wide I/O module, and let users wire eight individually pluggable sensors or actuators on one unit. Fieldbus couplers include Profinet, EtherCat, Modbus TCP, Ethernet TCP/IP and others. The high-speed bus works with as many as 256 DI/DOs in 20 μs.

DIN Rail Blocks    
Selos WT series of DIN-rail-mounted, screw terminal blocks have a push-in jumpering system for the company's screw terminals and provide a low- resistance and vibration-proof connection by seperating the steel spring for mechanical fastening from the jumper's copper current bar. The device's dual-channel jumpering permits extended jumper lengths or bridging of multiple potentials.
Wieland Electric;

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. The backplane's push-plug mechanism protects modules from reverse polarity. The bases feature a locking system for DIN-rail mounting.

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.
Sealevel Systems;

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. XNE modules have push-in, spring-cage terminals only, and are compatible with XN spring-cage base modules. Buses include EtherNet/IP, Modbus TCP, DeviceNet, Profibus-DP and CANopen.

Power I/O        
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 and 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 roughly #14AWG.
Beckhoff Automation;
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.
Direct I/O
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.
Belden/Lumberg Automation;

Fuse the Circuit
WTB2-FB130L IEC fuse holder terminal blocks have a current rating to 30 A and accept ¼- x 1¼-in. fuses. They have a built-in LED circuit to indicate when the fuse blows and funneled wiring entry with finger-safe IP20 terminals. Their 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 anal-yzes network strength and reliability, and conveys results througha bi-color LED. Transceivhers provide bidirectional communication between the gateway and device.
Banner Engineering;
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;

Sponsored Recommendations

Engineer's Guide to Advanced Motion and Mechatronics

This guide will examine the remaining differences between stepper and servo motors, new perspectives on motion control, the importance of both gentleness and accuracy with linear...

eBook: Efficient Operations: Propelling the Food Automation Market

For industrialized food production sectors, the megatrends of sustainable practices, digitalization and demand for skilled employees are underpinned by rising adaptability of ...

2024 State of Technology: Report: Sensors, Vision & Machine Safety

Manufacturing rarely takes place in a vacuum. Workers must be protected from equipment. And equipment must be protected. Sensing technology, vision systems and safety components...

Enclosure Cooling Primer

Learn more about enclosure cooling in this helpful primer.