Technology Update
By Jim Bachle
My earliest recollection of attempting to connect wires is of the early 1960s. I had witnessed the connection of wires to a "post" terminal and was sure that I could easily perform this task. I carefully separated the strands of the wire, formed a fork, placed them under the nut and began to tighten. After this task was accomplished, I plugged the transformer of my new Lionel train into the wall and flipped the switch. To my horror, I was greeted with the flashes and crackling of electricity. The consequences of my actions were enough to convince me that this magical "stuff" called electricity was not for me!
Over the years, my fear, but not my respect, diminished. I remember the "twisted-conductor/ball-of-tape" through to the "solder/heat-shrink" phases vividly. Tech classes in school and early field experience taught me the magic of NEMA-style terminal blocks and crude (by today's standards) connectors.
The mid-1980s brought IEC-style connectors into my world. I discovered high-density units with all kinds of exotic configurations and options. As a designer, I was in heaven. All of the possibilities of such high-density connectors thrilled me. The new era in control was fast upon us — bigger no longer meant better.
Primary aspects of the industry interconnect going into the new millennium are the ability to provide maximum flexibility and the ability to alter design and function within an accelerated time frame. The cause of these requirements is varied: changes in component technology, model changeover in a manufacturing environment or elimination of scheduled maintenance shutdowns in an effort to maximize throughput.
Exciting new component designs allow the use of universal connectors that can be utilized with printed circuit boards, rail-mounted terminal blocks and multiconnection devices. Previously, each manner of connection required components that were application-specific. Prior efforts to provide a plug-and-play solution were either a merger of rail-mounted terminal blocks and headers/connectors or components that were designed to fulfill a specific purpose. The ability to alter design criteria and function of the control scheme was a major undertaking that often involved a complete dismantling of the system.
Advancements within the enclosure industry currently make it possible to replace expensive "heavy connectors" with connectors and terminal blocks that occupy less space and dramatically reduce component costs. Wiring can be routed through a bottom "gland" in an enclosure and final connection is accomplished within, thus eliminating the requirement for the expensive gaskets and housings used in typical "through-wall" connectors.
Products in the interconnect industry that can meet the demands of greater flexibility with a wider variety of applications will increasingly be the most valued, in terms of both total cost and increased efficiencies.
JIM BACHLE is Electrical Products Manager, WAGO Corp., N120 W19129 Freistadt Rd., Germantown, WI 53022; (800) 346-7245; Web site: www.wago.com.
PCB Terminal Blocks
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The BLIDC 3.5 and BLIDC B 3.5 Connector Plugs feature IDC technology. The BLIDC 3.5 is available in two- to 16-pole versions, with or without mounting flanges for the secure connection of the plug to the pin header. The socket is said to enable 90° or 180° wire outlet angles from the same connector. The BLIDC B 3.5 "bus" version can reportedly be installed anywhere along the wiring, as required. Ratings for the products are 300 V, 7 A, with maximum cable size of 22 to 20 AWG. Also available are 3.5 mm plug connectors with screw or tension-clamp connections. Weidmüller Inc., Richmond, Va.
Terminal Blocks
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Female Connectors and Double-deck Terminal Blocks have been added to the X-Com System. The products are available as modular feedthrough and ground-conductor terminal blocks. They offer two plug-in connections within a reported thickness of 59 mm from the mounting rail top surface. Product design parameters are said to allow for maximum voltage/current ratings of 300 V, 10 A. Wire range is reported at 28 to 12 AWG. WAGO Corp., Germantown, Wis.
PCB-mount Terminal Blocks
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These PCB-mount Terminal Blocks are CSA-, VDE- and UL-listed and are reportedly manufactured under ISO 9002 certification. Styles include Euro, barrier, pluggable and spring types. Modified and customized variations are also available. Eby Co., Philadelphia, Pa.
Spring-clamp Terminal Block
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The 5.00 mm Type 609 Spring-clamp Terminal Block is said to ship wire ready and provide an easy-to-terminate, gastight connection. A tooless operation and a unique design are said to provide constant contact resistance and auto adjustment of spring force at each wire size. It is UL-listed and meets VDE requirements. With a wire range from 28 to 14 AWG, the pluggable block is rated to 250 V at 15 A, and is available in two to 24 poles. RIA electronic Inc., Eatontown, N.J.
Eurostyle Terminal Blocks
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The 8801 and 8802 Eurostyle Terminal Blocks are offered in 5.08 mm terminal pitch. The 8801 style is 10.00 mm high and is rated 10.0 A for maximum 16 AWG wires and 300 V continuous service. It has a continuous operating temperature range of -40° to 110°C. The 8802 style has a 35° entry, and is rated 17.5 A for 12 AWG wires. It too is rated for 300 V continuous service and has a continuous operating temperature range of -40° to 110°C. Both are UL-recognized and CSA-certified. Molex Inc., Lisle, Ill.
Terminal Blocks
Screw and Screwless Terminal Blocks with printed circuit-, rail- and panel-mounting options meet IEC standards and specifications. Eurostyle printed circuit configurations with conventional and depluggable options, double-deck PC connectors, surface-mount blocks with solder tabs, fused rail-mount blocks, plug and socket sets, transformer connectors and porcelain connectors are available. They are manufactured in ISO 9001-registered facilities and reportedly meet all safety approvals. Americor Electronics Ltd., Elk Grove Village, Ill.
Stackable Terminal Blocks
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These Terminal Blocks have contact pitches of 3.50 and 3.81 mm for board-mounting. They are reportedly molded to length, providing from two to 25 positions. Applications include security and alarms, HVAC equipment, elevators/ escalators, process controls, industrial machinery, power supplies and instrumentation. The products include housing interlocks in configurations for side- and top-wire entry, and accept wire sizes from 30 to 14 AWG (solid or stranded). Contact current and voltage ratings are 12 A and 150 V. AMP, a part of Tyco Electronics Corp., Harrisburg, Pa.
PCB Terminal Blocks
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Quix-Combicon PCB Terminal Blocks are said to utilize insulation displacement connection technology for a fast connection. Using a 5.08 mm (0.20") pin spacing, the products reportedly mate with all industry-standard 0.20" PCB-mount headers. Two to 16 positions are available, and a screw flange for additional security to the mating header is optional. The pluggable blocks accept 18 AWG wire and have a current-carrying capacity of 10 A at 300 V. Phoenix Contact Inc., Harrisburg, Pa.
Terminal Blocks
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The WKC/TKM Knife Edge Disconnect Series is designed to allow circuit testing without disconnecting wires. Built-in test points with a lever-disconnect switch are featured. Two types are included: the 5 mm WKC1/TKM35, designed for 24 to 18 AWG conductors, and the 6 mm WKC2.5/ TKM35, designed for 16 to 14 AWG conductors. Standard accessories include mounting rails, end and partition plates, covers, test plugs and marking accessories. Wieland Electric Inc., Burgaw, N.C.
Barrier Blocks
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The C3XM and C4XM Barrier Blocks are designed with integral protective covers, which are said to enable operation of each position while making the assembly safer. They have a current-carrying capacity of 15 A per pole at 300 VAC, and the tin-plated brass terminals accept 22 to 14 AWG wire. The green or black bodies are molded of polyamide 66, rated UL 94V-0. They are available in 0.300 or 0.375" pitch and two- or three-pole versions. E-Mark Inc., Shelton, Conn.
Compact Terminal Blocks
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The 32500 Terminal Blocks have 0.325" (8.25 mm) center-to-center spacing, and include offset pins in many terminal choices: base-mount, PC pin, wire wrap, turret and right-angle terminals. They are made from polypropylene material and have a UL and CSA 94 V-0 flammability rating. Rated 15 A, 300 V, they can accommodate a wire range from 22 to 14 AWG. One to 26 terminal positions are available. Top-termination or screw hardware options are also available, as well as custom-designed blocks. Curtis Industries Inc., Milwaukee, Wis.
Electronic Circuit Blocks
Electronic Circuit Terminal Blocks are designed for industrial control and automation applications. Standard and custom IEC DIN rail-mounted products are available. Several functions are featured, including voltage indication, over-voltage protections, kick-back protection and polarity-reversal protection. A prototyping terminal block PCB that enables the end user to test a new design or prototype a PCB for later production is also available. Automation Systems Interconnect Inc. (ASI), Carlisle, Pa.
PCB Terminal Blocks
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Two- and three-pole PCB Terminal Blocks reportedly interlock to any required length. The special "safe wire" metal plate locks down over the wire, reportedly eliminating fraying and breaking of stranded wire. Made from UL 94V-2 thermoplastic with temperature ranges up to 105°C, the products reportedly accept wire ranges from 26 to 14 AWG. The voltage is rated to 250 V at 10 A, and they are constructed of plated steel and tin-plated brass. Hoffman Products, Bohemia, N.Y.
Modular Terminal Blocks
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These PCB-mount Terminal Blocks are available in horizontal and 45° entry modular styles. Designed for use on high-density PCBs, the 45° entry blocks feature easy-access termination points and are constructed with the screw heads on the top of the blocks. Both designs are available with two and three terminal positions that can be interlocked to a maximum of 24 positions, and both accept 22 to 14 AWG wire. Termination points have a wire guard that helps prevent damage to conductors. Keystone Electronics Corp., Astoria, N.Y.
Power Distribution Blocks
SnapBloc Power Distribution Blocks are said to snap together and lock into place without tools. They are available in 24 connector styles for conductor sizes 14 to 500 MCM, and can be used with any combination of aluminum or copper conductors. The modular products reportedly utilize connectors that are UL-listed and CSA-certified for 600 V, and feature one-piece electrical continuity, a 90°C temperature rating and single or double main cable entry with two, four, six or 12 taps. They are manufactured from 6061-T6 aluminum alloy, and are electro tin-plated. ILSCO, Cincinnati, Ohio
Harsh Environment Blocks
These Terminal Blocks are manufactured with nickel plating and stainless-steel screws. They are reportedly suitable for the harshest environments. The blocks are said to be designed for durability, which is said to allow an increased reliability for connections. Woertz-USA, Colmar, Pa.
