Terminal Blocks and I/O Grow Up

Several Trends Occurring in the Design and Development of These Products Are Used by Machine Builders for Their Control Applications

By Rick Pedraza

This month's roundup of I/O products shows several trends occurring in the design and development of terminal blocks and I/O systems used by machine builders for their control applications, including more functionality and wider applicability.

Bishop & Associates, a research firm specializing in the connector market, reports that the terminal block market grew 5.4% in 2005 to $2.01 billion, with Europe consuming 44% of the world demand. North America is second with a 22% market share, while China, Japan, Asia Pacific, and the rest of the world share the balance of 33%, says the report. Forecasts show the terminal block market increasing to $2.6 billion by 2010.


Worldwide shipments of distributed/remote I/O for industrial markets totaled $3.2 billion in 2005, and are forecast to reach nearly $4.3 billion by 2010, according to a new study conducted by Venture Development Corp.

The Europe, Middle East, and Africa (EMEA) market was the largest consuming geographic region of distributed/remote I/O in 2005, accounting for 47% of worldwide shipments. North America accounted for about 25%, Asia-Pacific for 24%, with the remaining shipments going to the Latin American (Mexico, Central and South America) market.

The study says the most significant trend related to bus/network connectivity "remains the ongoing shift to Ethernet networks and the displacement of proprietary buses/networks by open buses/networks in general."

Other trends include higher data converter resolution, higher data sample rates, transparent interchangeability with equivalent connectors, blocks and modules, and the proliferation of safety buses/networks.

Our roundup reveals that the number of new products and systems that connect via industry-standard protocols is gaining momentum. Most of the products found below feature Ethernet or fieldbus connectivity with detachable connections. Nearly all of the new terminal blocks on the market support DeviceNet, Profibus, CANopen, Modbus, and AS-Interface.

Product Roundup:

Connectivity Now
IP20 BradControl block I/O system connects industrial I/O devices to a PLC or PC controller over an industrial network. The ribbon cable-based expansion bus handles inter-module communication, operates at 11 MBaud, is 6.5 m in length, and can accommodate up to 10 groups of modules. The expandable system accommodates a maximum of 512 channels of I/O as discrete inputs, discrete solid state outputs, discrete relay outputs, analog inputs, and analog outputs.
Woodhead Industries
(847) 236-9300

Device Couplers
TG200 TrunkGuard fieldbus device couplers are available with four, eight, or 10 fieldbus spurs, and work with Foundation fieldbus H1 and Profibus-PA interfaces. Couplers can be DIN-rail mounted, or enclosed in IP66-rated, glass-reinforced polyester or stainless steel enclosures. Up to 32 fieldbus devices can be accommodated in one segment. Automatic segment termination activates when the coupler is the last fieldbus junction device in the segment.
Moore Industries-Intl.
(818) 894-7111

Thick and Thin
netFlex-10M cables perform more than 10 million flex cycles in c-tracks and robotic applications. DeviceNet Thin and Mid specification can be ordered as premolded cordsets with Mini or Micro connectors. Mid-spec standard cable has a maximum trunk length of 300 m for 125 kbit/s and 200 m for 250 kbit/s. 600 V Thick Tray cable allows placement in the same cable tray as power cables and is available with Mini connectors as single or double-ended cordsets.
(804) 379-2010

Dedicated to Speed
VBA I/O modules for AS-Interface specification 3.0 support extended addressing with four inputs and four outputs for up to 62 nodes per network. G2 node provides IP67 protection in a low-profile flat housing, with M12 quick-disconnect I/O. G4 node provides IP65 protection, input wires that can be field cut to length, and vibration-resistant, cage-tension-spring terminals for I/O connection. KE switch cabinet module is IP20 protected with a 22.5 mm housing for minimal enclosure space requirements.
(330) 486-0001

On-Machine I/O
1732 Armor Weld­Blocks combine I/O circuits, power supply and network adapters in one sealed IP69k housing. Blocks of 24 VDC digital I/O mount directly on equipment near sensors or actuators. Nickel-plated, cast-aluminum resists the effects of weld slag and magnetic fields created by high currents at weld points found in close proximity to the weld head. The light protective housing makes it suitable for end-of-arm robotic applications.
Rockwell Automation
(440) 646-4084

Process of Elimination
750-670 I/O module includes stepper motor and servo drive control in a compact 12-mm package. Integrating stepper motor and servo drive control into the fieldbus node (PLC or PC-based) eliminates the need for a separate motion controller. Communication is via RS-422 interface, and is controlled by a variable output frequency of 0-500 kHz. It has 24-bit resolution and eight LEDs for status indication and diagnostics.
(800) din-rail

Back to Base 
Advantys OTB distributed I/O system includes three communication bases for various fieldbuses, CANopen, Ethernet TCP/IP or Modbus RS-485 serial line. Each communication base is 55 mm wide, includes 20 I/O totaling 12-24 VDC inputs, six relay outputs and 2-24 VDC solid-state outputs. The system uses a nanocontroller platform and can be fitted with most expansion I/O modules. Expansion and interface modules enable configurations of up to 132 digital I/O and up to 48 analog I/O channels, or a mix of both.
Schneider Electric
(800) 392-8781

Snap to It
Snap-AITM-8 thermocouple input module accepts up to eight channels of temperature or mV input from a variety of thermocouples, or any -75 to +75 mV device input. It offers resolution to 0.1% of range (75 µV), accuracy of up to 0.8 °C, factory calibration, and built-in cold-junction compensation. Transformer isolation reduces noise and installation problems, and 4,000 Vrms optical isolation (4,000 V of transient protection for 1 ms) from other modules on a Snap rack, and is UL and CE approved.
Opto 22
(800) 321-opto

Stack 'em Up
EtherStax Model 2113 features 96 channels of discrete I/O  with Modbus TCP/UDP/IP communication to a host controller. Dual network ports support 10/100BaseTX copper and 100BaseFX fiberoptic connections, and provide a redundant communication path for critical applications. An embedded web page makes configuration menus accessible with any web browser to eliminate programming. Stackable aluminum enclosure resists shock and vibration. Nearly 300 I/O stack in an 8x7 ft footprint.
(248) 295-0880

Gleaming the Cube
Cube67 modular fieldbus system supports Ethernet/IP and Profinet. Bus nodes have an integrated web server for easy installation and servicing. Decentralized IP67 I/O system features parameterizable and pluggable digital and analog inputs and outputs, and safe outputs to reduce connecting time and components.

New Terminals on the Block
IEC terminal blocks provide transparent interchangeability with a wide range of equivalent connectors, blocks, and accessories. Blocks are molded from a UL 94V0 material, with metal clamping bodies made of a nickel-plated copper alloy. Screws are plated to prevent corrosion, and all materials are RoHS compliant. Models range from single level to two and three levels, sliding link and disconnect blocks, fuse blocks, sensor blocks, miniature and sub-miniature, pluggable, and high current.
(877) 650-5160

Switch Channels
EL6601 switch terminal enables connection of peripherals with Ethernet connectivity into EtherCat networks. The terminal provides transparent and collision-free Ethernet communication of connected devices through the system and can be installed at any point within an EtherCat node. Standard Ethernet frames are tunneled through the EtherCat protocol. The connected master acts like a Layer 2 switch, redirecting the Ethernet frames to the respective devices according to IP address information.
Beckhoff Automation
(952) 890-0000

Push-in Terminal Blocks
P Series terminal blocks with push-in connection technology provide secure and reliable terminations. PDU 2.5/4, PDU 6/10 and PDU 16 have wiring ranges of 20-10 AWG, 14-8 AWG, and 14-4 AWG. The push-in connection system is suitable for flexible wires with crimped-on ferrules with or without plastic collars, and ultrasonic bonded wires. Features include feed-through and ground terminal blocks with two, three and four connections, as well as dual-level, disconnect, and isolating neutral terminals.
(804) 794-2877

Step on the Accelerometer
SCM5B48 accelerometer input module isolates, filters, and amplifies sensor output, yielding a high-level analog voltage output. Excitation current, signal gain, and filter high-pass and low-pass cutoff frequencies are field-configurable through a set of slide switches. Six poles of filtering result in +100 dB of normal-mode rejection for frequencies above cutoff. Features include input protection to 240 Vrms continuous, with an operating temperature range from -40 to +85 °C.
(800) 44-7644

According to Spec
IEC terminal blocks meet UL, CSA, and IEC specifications and are rated for Code 1 factory wiring only, and Code 2 factory and field wiring. Screw clamp is available from 20-232 A; spring clamp from 20-50 A; and miniature panel mount from 20-35 A, in both spring and screw clamp. Eight colored terminal blocks provide easy circuit identification. Blank, standard, or custom markers are available from 5-20 mm wide.
(724) 775-7926

Speedy Conversion
X20 analog input modules offer a high conversion resolution. Each channel can be configured for 0-20 mA or ±10 V. The module has a conversion time of 50 µs, and includes an internal electronic slave pointer for minimum and maximum values. Various sampling methods can be configured using definable trigger conditions or a direct start from the CPU. Sample rates can be configured from 100 Hz to 20 kHz.
B&R Industrial Automation
(770) 772-0400

Communication Is Crucial
SX5L communication terminals use network variables for transmitting and receiving data over LonWorks. The network can be connected in star, loop, bus or a combination. Modules have detachable finger-safe terminal blocks to protect against electrical shock and can be DIN-rail or panel mounted. Terminals available include digital I/O, analog input, PT100 ohm, pulse input, and remote-control relay control.
(800) 262-idec

Digital I/O
Adam-4150 and 4168 digital I/O modules provide high noise immunity (1 kV surge protection on power inputs, 3 kV EFT, and 8 kV ESD protection), broad operating temperature range, power input range 10-48 VDC, LED display to monitor the status of the address settings; digital filter function; digital output support pulse function; and Modbus RTU protocol.
(877) 294-8989

Analog Combination I/O Modules
F2-8AD4DA-1 16-bit analog combination I/O module has eight channels of current input sinking and four channels of current output sourcing. The ranges on the module are 0–20 mA input and 4–20 mA output. F2-8AD4DA-2 is a combination I/O module with eight channels of voltage input and four channels of voltage output. The ranges on the module are 0–5 V and 0–10 V input and output, and they support selectable input resolutions of 16 bit, 14 bit, and 12 bit, with output ranges fixed at 16 bit.
(770) 889-2858

I/O Module Uses Standard Server
DIN/panel-mount Ethernet bus coupler module uses Modbus TCP/IP for data transfer between controller and sensor-level devices. DIN-rail or panel-mounted, the bus coupler consists of a base module for the fieldbus interface and diagnostics. The Ethernet module offers the benefits of Modbus TCP/IP while maintaining diagnostic and wiring features of the standard bus coupler. It has a data transmission rate of 10/100 Mbps via a CAT5 twisted-pair cable. An RJ45 socket is provided for fast 10/100 BaseT4 connections.
Wieland Electric
(800) wieland

Smart Slave Simplifies Troubleshooting
DRT2 smart DeviceNet slave monitors both I/O status and network communications status, and lets users remotely monitor and diagnose low network voltage, communication errors, and short circuits for connected devices. When combined with configuration software, users can connect and monitor the factory floor network over an Ethernet connection without needing any control programming or interruption.
Omron Electronics
(866) 88-omron

Connector Family in B and C Sizes
Minifast B and C cordsets and receptacles are available in six to 12-pin configurations for power and signals to factory automation equipment. Paired with 16 AWG cable (18 AWG also available) the six-pin minifast offers a full 9 A of current-carrying capability, and the 12-pin minifast can handle 6 A.
(763) 553-7300

Built-in Conditioner
Compact FieldPoint cFP-AIO-600 analog I/O modules take advantage of built-in signal conditioning to connect directly to high-voltage, mA, and low-voltage signals, thermocouples, RTDs and strain gauges. The modules feature 2,300 Vrms transient overvoltage protection between the input channels and the backplane. The modules feature plug-and-play operation.
National Instruments
(800) 258-7022

DPS3000 Series scanners monitor up to seven individual inputs. DPS3200 and DPS3204 channels can be programmed to accept different inputs, while DPS3100 and DPS3104 are limited to one input type on all channels. All models automatically can scan and display each channel, show elapsed time, display the channel with highest or lowest reading, scan each channel’s deviation from a preset setpoint, or show differential between a master channel and other inputs.
Omega Engineering
(800) tc-omega