Smaller, faster, easier

Trends in terminal blocks are not as fickle as trends in fashion. However, like fashion, everyone wants to keep on top of what's hot and what's not. Easier, faster, smaller, and more economical are buzzwords often used when describing trends in terminal blocks. "Everything is getting smaller and easier to use.

By Antonia McBride, Assistant Editor April 1, 2000
TRENDS IN TERMINAL BLOCKS
  • Smaller, easier to use

  • Reduction in time and cost associated with wiring

  • More intelligent components

Trends in terminal blocks are not as fickle as trends in fashion. However, like fashion, everyone wants to keep on top of what’s hot and what’s not. Easier, faster, smaller, and more economical are buzzwords often used when describing trends in terminal blocks.

‘Everything is getting smaller and easier to use. Plus when you reduce the panel size, you reduce the cost of terminal blocks,’ said Dean Norton, product manager for Wieland Electric Inc. (Burgaw, N.C.).

Control Engineering ‘s new study looks at trends in the current terminal block market. Fifteen hundred CE readers were polled in part to determine which factors are most important in the purchase decision for terminal blocks. Three hundred seventy-six completed the questionnaire for a response rate of 25%. In all, 94% of the respondents recommend, specify, and/or buy terminal blocks. Of those 94%, upon which the rest of the results are based, 74% recommend, specify, and/or buy terminal blocks for in-plant use; and 33% do so for OEM (resale) requirements.

When asked what termination methods were used, and which were preferred, nearly nine out of ten, 89%, of the respondents currently use a screw type termination mix. About six out of ten, 61%, of the respondents also prefer a screw termination method. Screwless, at 28% usage and 15% preferred, came in a distant second. Values add to more than 100% due to multiple responses.

Neater packaging

Companies are moving away from similar looking terminal blocks and are now focusing on what is most useful in different situations.

Insulation displacement connector (IDC) technology, reduces wiring installation time and labor, especially in high-volume wiring applications.

In 1999, PCD Inc. (Peabody, Mass.) introduced its fixed-mount terminal blocks in intrinsic safety blue. According to PCD, these terminals limit the thermal and electrical energy in a hazardous environment and are incapable of causing an explosion in the surrounding atmosphere.

Telemecanique AB1 terminal block from Square D/Schneider Electric (Palatine, Ill.) not only reduces installation time but is available in seven colors. ‘In the plant, the additional colors make it easier to troubleshoot, so products can be repaired faster for optimal efficiency,’ said Larry Sunday, Square D/Schneider Electric product manager.

Wago’s (Germantown, Wis.) series 769 terminal block provides ‘X’ number of connection combinations, which use terminal blocks and plugs, designed to create one self-contained plug-in connection system with unlimited variations.

Compact packages

Among industry segments represented by the survey respondents, availability and ease of installation were the characteristics perceived most important on average when purchasing terminal blocks. Cost, specifications and wide variety of special blocks were close behind.

Just as fitting the clothes to the person matters, with terminal blocks, installation and servicing are more important. Automation Systems Interconnect Inc. (Carlisle, Pa.) carries standard and custom IEC DIN-rail-mounted terminal blocks in a small package in a family of 27 circuits

Phoenix Contact (Harrisburg, Pa.) recently expanded its QUiX (IDC) terminal block line. QUiX is designed to save up to 60% installation time and can be terminated with no special tools or stripping of conductors. The blocks also feature a dual-jumper channel that accepts snap-in bridges to make any combination of points common.

Expanding on the ease of installation in the Compact I/O and MicroLogix 1500 packages, Rockwell Automation (Milwaukee, Wis.) introduced the Allen-Bradley Bulletin 1492 wiring system for 1769 I/O. The Bulletin 1492 wiring system is said to further reduce time and costs associated with wiring allowing plug-and-play installation.

When polled on what requirements for terminal blocks changed most over the past five years, many respondents mentioned density, size, and spacing. These requirements account for changes in attitudes from manufacturers of terminal blocks.

So what is in the future for terminal blocks and end-users? Smaller sizes, easier installation and lower costs will all become important trends end-users can continue to anticipate to help in finding the best fit in terminal block options.

Terminal blocks products

For more information on terminal blocks, visit www.controleng.com/freeinfo .

Additional providers of terminal blocks include Siemens Energy & Automation ; Cutler-Hammer . For a broader listing of terminal blocks manufacturers, go to the Control & Automation Buyers Guide at www.controleng.com/buyersguide .

Electronic circuit

Carlisle, Pa. -Electronic circuit terminal blocks offer standard and custom IEC DIN-rail mounted terminal blocks. The family of 27 circuits offers several functions, including voltage indication, over-voltage protection, kick-back protection and polarity reversal protection. In addition, a prototyping terminal block circuit board is available, which enables the end-user to easily test out a design or to prototype a circuit board for later production. The current bar for the screw clamp terminal blocks is surface-mounted to the printed circuit board. www.asi-interconnect.com Automation Systems Interconnect

Advanced IDC

Burgaw, N.C. -Designated the ‘taris’ IDC (insulation displacement contact) Series, Wieland’s latest system reduces wiring installation time and labor, especially in high-volume wiring applications. The complete product line in the taris Series includes 5-mm and 6-mm width blocks in feed-through, ground, disconnect, fuse, double-tier, and 1-in-2-out versions. In addition, there are several versions with electronic functions, including arc suppression, reverse polarity protection and voltage indication terminal blocks. At 5 mm and 6 mm wide, they are said to be the thinnest blocks in the industry to accept 14 AWG wire. www.wielandinc.com Wieland Electric

ZMAK motor terminal

Richmond, Va. -To save space on the mounting rail for applications in confined areas, Weidmuller Inc. now offers ZMAK, said to be the smallest motor terminal with tension clamp technology currently available. With a width of .197 in. (5 mm) and a UL-rated current of 25 A, ZMAK can be easily snapped onto TS 35 mounting rails. It enables six three-phase ac motors to be connected on a mounting rail of 1.2 in. (30 mm) in length, compared to five motors with conventional motor terminals. A single ZMAK terminal block can connect a three-phase ac motor. It enables correct connection of the three phases -and the protective conductor, with cross-sections of 26-12 AWG and rated voltages up to 300 V. www.weidmuller.com Weidmuller Inc.

Mountable fuse blocks

Cumming, Ga. -As part of a triple level family of terminal blocks, Automationdirect.com released 600 V, 30 A DIN-rail mountable fuse blocks. The blocks are available with a long-lasting neon indicator light for quick troubleshooting. The permanently attached pivoting fuse door is said to simplify and speed fuse replacement without using tools. The IP20 rated fuse blocks also offer lockout/tagout compliance via the lockable extraction door to meet OSHA requirements. www.automationdirect.com . Automationdirect.com

IEC type blocks

Palatine, Ill. -Spring clip termination in the new Telemecanique AB1 terminal blocks from Square D/Schneider Electric are said to reduce installation time by 50%, compared to conventional solutions. The IEC-type terminal blocks are available in seven colors, making it easier for wire tracing. The AB1 is available in 96 models, for a wider range of applications. For an equipment manufacturer or panel builder, the AB1 offers increased versatility and reduced installation time. In the plant, additional colors make it easier to troubleshoot, so products can be repaired faster for optimal efficiency. www.squared.com Square D Company

Intrinsic safety blue

Peabody, Mass. -PCD has announced that its fixed-mount terminal blocks now come in intrinsic safety blue. This internationally recognized color clearly identifies the terminals of the intrinsically safe (IS) circuits of electrical devices. IS circuits limit the thermal and electrical energy in a hazardous environment and are incapable of causing an explosion in the surrounding atmosphere. Also available are ELM Stackable Modular terminal blocks and EL1M, EL2M, and EL3M Multi-tier modular terminal blocks in intrinsic safety blue, specifically for processing, measurement and control applications. www.pcdinc.com PCD Inc.

PLC connections

Irving, Tex. -Entrelec expands its Interfast product line with the introduction of Interfast MS. Interfast MS-a complete system including pre-wired and tested PLC cables, plus ready-to-go, compact, interface modules-allows easy connection of programmable logic controllers to field and control equipment. Cables consist of a PLC swing arm, which plugs into the PLC/IO connections, a cable length specified by the customer, and an interface module connection. Interface modules, supplied in a terminal block housing, include one-to-four wire circuits, isolating relays or optocouplers, or a custom combination of choice. www.entrelec.com Entrelec

Fast, simple wiring

Milwaukee, Wis. -Rockwell Automation has introduced the Allen-Bradley 1492 Wiring System for 1769 I/O modules, a combination of interface modules, pre-wired, and I/O ready cables, specifically designed for the MicroLogix 1500 micro-PLC applications. The Wiring System connects to the 1769 I/O digital and analog modules via pre-wired cables and mounts on a standard DIN-rail. The 1492 Interface Module capability includes feed-through, LED, fused, relay, and expandable options. www.rockwellautomation.com Rockwell Automation

Relay terminal blocks

Schaumburg, Ill. -Omron’s line of Relay Terminal Block products can be connected to anyone’s controller through industry standard MIL connectors on every relay block. Available in 8- and 16-relay versions, visual indication of operation status is either built into the block or available on relay. All relay blocks incorporate lever mechanisms to allow for easy removal and replacement of the relays with no tools. www.info.omron.com Omron Electronics Inc.

Small overall dimensions

Germantown, Wis.- Wago recently announced release of a new addition to the X-Com, series 769 terminal block. The 769 Series provides ‘X’ number of connection combinations which utilize terminal blocks and plus that are designed to create one, self-contained plug-in connection system. Unlimited variations are said to save time and money and allow pre-assembled modules to be plugged into DIN 35-rail mounted receptacle terminals. www.wago.com Wago