Basic 'feed through' terminal blocks have one wire connection point on each side, with a conductive bar between them. This electrical portion resides inside an insulated housing. Some terminal blocks mount directly to back panels, while other styles install on DIN rails or may be stacked side-by-side to save space. Designers must select terminal blocks with the right voltage, ampacity and physical sizes to match the application.
Standard terminal blocks can be bulky and consume valuable panel space. The classic screw-type connections often have screws and washers that can be lost, or they may require ring or fork lugs to be crimped on to wire ends. Screwing down each terminal connection point requires tools and takes a tremendous amount of time. Once assembled, the screws must be correctly torqued to ensure a proper connection. Too loose will cause the wire to overheat or disconnect, while too tight can result in a stripped screw or snapped screw head. Some designs use a spring cage-type connection, which is a screwless design that can accept a bare wire, or a wire with a pin ferrule crimped on to the end. However, this style still requires a tool for both wire insertion and wire release, which is still not optimal, taking up time and requiring the proper tools to accomplish.
Dinkle offers DKN Series screw-type terminal blocks and AK Series spring cage type terminal blocks, because some users and industries have specific technical, commercial, or historical reasons for continuing to use these traditional products. However, each of the potential issues with screw-type and spring cage type terminal blocks can be overcome by using newer DP Series multi-level push-in design (PID) terminal blocks offered by Dinkle (Figure 2).