Choose Your Weidmuller Terminal Block Series

Terminal Block Overview

For all applications that require connecting wires together, you just can't make a better choice than Weidmuller's DIN-Ral Mounted terminal blocks. There are five excellent reasons for making Weidmuller DIN-Rail Mounted Terminal Blocks your choice for demanding applications.

1. Efficient Use of Space

DIN-Rail systems allow designers to package increased functionality in less space than ever before!

Some of the Thinnest modular terminal blocks available

The WDU 2.5 and ZDU 2.5 are only 5 mm (0.195 in.) thick! You can install 60 of these feed-thru terminal blocks per foot of DIN mounting rail. Only slightly larger are the SAK 2.5 and IDU 1.5 terminal blocks at 6 mm in width. No matter which Weidmuller modular terminal block you choos, t will offer a significant improvement over barrier-type terminal strips and channel mounted terminal blocks.

Mounts on industry standard DIN mounting rail

Weidmuller terminal blocks mount on industry standard DIN-rail, proiding an excellent complement to other rail-mounted products like power supplies, contactors, etc. They can easily be combined to create the configuration required by your application.

2. Safe and Secure Connections

Accidental contact with live circuits or metal parts can damage equipement as well as cause serious injury to personnel. With Weidmuller terminal blocks, every effort has been made to elimiate the potential for accidents. The design of most of Weidmuller's modular DIN-rail mounted terminal blocks reduces the exposure to current carrying components and helps insure the safety of the equipment operators.

Insulated, touch-safe design

All current carrying parts are completely insulated for touch-safe, dead-front operation. Screws are recessed to avoid the potential for shock or injury.

Insulated, recessed parallel jumpers

Jumpers for the W-Series, Z-Series, and I-Series terminal block product lines are fully insulated and installed in a recessed center channel. The ability to do double row jumpering reduces the need for external jumper combs. With the WDU 2.5 terminal block, innovative pluggable jumpers allow up to three rows of jumpers to be inserted into the the jumper channel.

3. Fast and Easy Installation

Weidmuller understands that careful design yields increased eficiency for customers. We pay attention to the details that make your installation easier.

Screw and tension clamp terminals feature funneled wire entries and molded wire stops to insure that properly stripped wires will be inserted to the proper length and clamped securely. Weidmuller's screw clamp terminals are shipped with clamps in the open position to reduce installation time. Tension clamp and IDC terminals provide wire entry from the top for ease of installation even in confined locations. The IDC blocks also eliminated the need for wire stripping.

The marking aras on Weidmuller's modular DIN-rail mounted terminal blocks allow application specific (or custom) marking, thereby reducing the need for other labels.

As an additional service, SCS also offers fully customized and pre-assembled complete terminal block rail assemblies on DIN rail cut to your specifications. All you have to do is fasten the pre-assembled DIN-rail system to your panel and wire it up! Click here for more information on the terminal block rail assembly services provided by SCS.

4. Wire termination technology that set the standard

The clamp must reliably connect the wires, both mechanically and electrically, with an insulation material that keeps it safe for users.

Weidmuller is the acknowledged leader in wire termination technology, with three distinct types of terminations -- screw clamp, tension clamp, and insulation displacement clamp (IDC)

Screw clamp technology

The Weidmuller screw clamp works well with nearly all sizes and types of wire and requires no special wire preparation. Just strip the wire, insert it into the block, and tighten the screw clamp. The design deliers a secre and reliable connection that is second to none.

High Contact Force:

Even the best materials are not effective without the necessary contact force between the wire and the current bar. High contact force is achieved by the design of the Weidmuller screw clamp system. A torque of 6.02 in. lb (0.68 Nm) on the WDU 2.5 clamping yoke provides a contact force of 169 ft. lbs (759 Nm). Clamps with a low contact force allow the conductor to move or pull-out, with the potential for contamination of the connection point and increasing contact resistance.

Self Locking Design of the Weidmuller Cage Clamp

High contact force is only effective if it is continuous. As the clamping screw is tightened, the clamping yoke draws the conductor to the current bar (2). Once the proper torque is applied, the upper part of the clamping yoke opens and locks clamping screw in place (3). This design makes the Weidmuller cage clamp mechanism highly resistant to vibration and insures your termination reliably stays connected.

Serrated Clamps and Current Bars:

In addition to high continuous contact force, all clamps and current bars in the Weidmuller cage-clamp terminal block product lines have serrated surfaces to increase the force required to pull out the wires. This means that your installation is more reliable and stable when maintenance personnel are working on the equipment.

Tension Clamp Technology

The Weidmuller tension clamp works well with nearly all sizes and types of wire and requires no special wiring preparation. Just strip the wire, open the tension clamp, insert the wire, ad release the tension clamp. This design delivers a secure and reliable connection for any application and is especially suited to installations where vibration may be a concern for the designer.

Flexible Design of Weidmuller Tension Clamps

The tension clamps have a top entry orientation, which means te wire and screwdriver entries are in the same plane. This design feature, combined with the large wire opening allows for quick and easy installation. In addition, the tension clamp will accept solid or stranded wires, as well as stranded wires with ferrules. (Click here for more information on wire ferrules)

Low Voltage Drop:

High, continuous contact forces keep the voltage drops low. The voltage drops across the Weidmuller clamping system is considerably lower than the limit required by VDE 0611.

Gastight Connections:

Even when using flexible wires without ferrules, the Weidmuller clamping system is gastight according to DIN 41640, Part 76 for aggressive atmospheres. Gastight means that corrosive gases cannot get between the wire and the current bars, thus keeping contact resistance and voltage drop to a minimum.

Even when using flexible wires without ferrules, the Weidmuller clamping system is gastight according to DIN 41640, Part 76 for aggressive atmospheres. Gastight means that corrosive gases cannot get between the wire and the current bars, thus keeping contact resistance and voltage drop to a minimum.

Maintenance Free Clamps:

Once a Weidmuller clamp has been securely tightened, you can forget about it! The clamping system has been verified by thermally aging the yoke at 130 deg C for a period of 168 hours. Subsequently, the clamping system was subjected to a vibration test at 20 times the acceleration due to gravity for another 168 hours. Even after this testing, the pull-out force was still 6 times the minimum value according to VDE 0611, and the voltage drop remained unchanged! You can trust the Weidmuller clamping system to be one of the most stable and reliable in the industry.

5. The Best in Terminal Block Materials are used for Weidmuller Modular Terminal Blocks

The materials chosen by Weidmuller for their terminal blocks are distinguished byt their durability under a wide range of conditions.

Steel is chose for strength

The mechanical system in the Weidmuller screw clamp is made from hardened steel for superior strength and has been electro-plated with a zinc-chromate coating to inhibit corrosion. The mechanical system in te Weidmuller tension clamp are made from stainless steel for superior strength and longevity.

Copper for conductivity

The current bars in all of Weidmuller's modular terminal block product lines are made of copper (Cu) and have been plated with a tin-lead coating. The tin-lead (Sn-Pb) plating guarantees exceptionally good contact while providing excellent corrosion resistance. The result: even after years of operation, voltage drop and contact resistance are negligible.

Choice of Insulating materials

All insulating materials used by Weidmuller for modular electrical terminations are asbestos-free and contain no cadmium based color pigments. Furthermore, no flameproofing agents with a halogen or phosphorus base are used. The insulation material of the SAK-Series modular terminal block product line is available in polyamide or melamine.

Wemid for safety

The insulation material used in Weidmuller's W-Series, Z-Series, and I-Series modular terminal block product lines is Wemid, a thermo-plastic material that combines the non-burning characteristics and wide operating temperature range of melamine with the robust mechanical properties (or flexibility) of polyamide. Wemid withstands a continuous operating temperature of up to 248 deg F (120 deg C) and has earned the highest possible flammability rating in its class: UL 94 V-0 (non-burning).

Thermoset plastics:

All thermoset plastic (KrG and KrS) materials used in Weidmuller's modular terminal block product lines are specified and controlled in accordance with DIN 7708 and other international standards. Thermoset plastics have high dimensional stability, negligible water absorption and an excellent comparative tracking index.

Melamine (KrG) is an aminoplastic molding compound with type FS 150 organic filler to DIN 7708, which is characterized by a high continuous operating temperature and high fire resistance. It is UL 94 V-0 (5 V-A) (non-burning) rated.

Thermoplastics:

Polyamide (PA) is the most commonly used plastic for modular terminal blocks. PA absorbes very little water, which makes the terminal blocks flexible and resistant to fracture. Its electrical characteristics are comparable to those of the thermoset plastics, while trade-ffs must be made regarding its burning behavior and continuous operating temperatures. Many Weidmuller terminal blocks are made of thermoplastic materials: Polyamide 66 having a UL 94 V2 (self-extinguishing) rating.

Completing the DIN-Rail Terminal Block Assembly

Mechanical - The accessories you need to complete your terminal block rail assembly

These accessories are used to mount the assembly. Required accessories include the DIN-rail, end plates and end brackets. Partitions are optional.

DIN-Rail for Mounting Terminal Blocks

The terminal blocks mount onto the DIN-rail and the rail is mounted onto the panel. The length of rail required is the sum of the width of all the components placed on the rail. Include in your calculations the width of terminal blocks, end plates, end brackets, and partitions. Add a tolerance of 0.2mm per terminal block and 50 mm for mounting slots or holes. You may also want to leave additional space for future expansion and the associated terminal blocks that may be required.

End Plates

End plates must be used for the last block in an assembly or whenever the open side of a terminal block abuts a smaller block. Pro-tip: Colored end plates may be used to identify the boundaries of circuits on a rail assembly.

End Brackets

End brackets are used on both ends of the DIN-rail terminal block assembly to hold the blocks in place on the rail. Therefore, two end brackets will be required for each grouping of terminal blocks.

Partitions

Partitions provide visual and electrical separation between groups of terminal blocks in an assembly.

Electrical - Accessories for making the right connections

These accessories are used to modify the electrical circuit or connections. They include jumpers, test plugs (and associated test sockets), and fuses.

Jumpers (or Cross-connections)

Jumpers are used to distribute current to other terminal blocks. Jumper assemblies are inserted into the jumper recess of a terminal block and fastened to the current bar. Feed-thru terminal blocks can typically accommodate two separate jumper assemblies (for example WQV jumpers). Some blocks, such as the WDU 2.5, can accomodate up to three of the ZQV-series pluggable jumpers. Jumpering does not add to the thickness of the block and will not change your rail assembly length calculations.

Test Plugs and Sockets

Test plugs and sockets make it possible to attach test equipment to the terminal block. This may be require for factory acceptance testing or may make your application more functional by providing convenient access test points for your maintenance personnel.

Fuses - Cartridge-type fuses for Weidmuller modular fused terminal blocks

Fuses for Weidmuller fused terminal blocks are available in 4 sizes: 5 x 20mm, 5 x 25mm (pop-up indicating type), 1/4" x 1-1/4", and 13/32" x 1-1/2". These fuses cover a wide range of current ratings as well as providing options for the speed with which the fuse will "blow". Click here for a selection of Weidmuller's W-Series modular fused terminal blocks.

Identification - Marking your terminal blocks

By marking your terminal blocks and rail assemblies, you create a well-organized, easy-to-read service panel. Weidmuller offers a variety of tags pre-printed with symbols, letters, or numbers, as wel as blank tags for custom printing requirements. These tags can be marked horizontally or vertically, depending on the mounting orientation of the terminal block rail assembly. Click here to see the selection of marking options.

Tools and Wire Ferrules

Weidmuller also offers a variet of tools to simplefy the assembly, including screwdrivers, wire strippers, and wire ferrule crimping tools. A full line of ferrules are available for use with stranded wire.

Good tools simplify the installation process. Using a properly sized screwdriver with the correct sized blade, for instance, will help insure the proper torque on the screw and minimize the chance of damage o the screw and/or terminal block. Wire strippers should be easily adjustable to the proper strip length required.

Wire ferrules, while not required for many installations, simplify the insertion of the finely stranded wire into the terminal blocks. They are particularly useful when the fine stranded wire is frequently disconnected and reconnected. This increases the likelihood of a "whisker" on the outside of the block. This condition can cause intermittent signal errors that can be difficult to troubleshoot. If you use wire-end ferrules, choose the ferrule attachment tool (or wire-ferrule crimper) with the proper die configuration for the ferrules and wire size being used in the application.