Purchase now: Allen-Bradley 1756-TBCH 36-Pin Removable Terminal Block
Atlantechdrives provides you the 1756-TBCH, a high-density 36-pin cage clamp Removable Terminal Block (RTB) for the ControlLogix 1756 I/O platform. This essential accessory is required for connecting field wiring to high-density modules such as the 1756-IB32, 1756-OB32, and all isolated modules (denoted with an «I») that require more than the standard 20 pins.
- Pin Count: 36 Pins
- Connection Type: Cage Clamp (Screw-down)
- Module Compatibility: 1756 High-Density and Isolated I/O
- Wire Gauge: 22 AWG to 14 AWG
- Housing: Included with deep-well for wire management
Technical Excellence: High-Density Connectivity
The 1756-TBCH is engineered to provide a secure and vibration-resistant connection point for complex I/O configurations. As ControlLogix modules evolved to include 32-point density and individual channel isolation, the standard 20-pin RTB became insufficient. The 1756-TBCH provides 36 independent termination points, allowing for the connection of multiple commons and individual returns. The cage clamp design ensures that the wire is compressed evenly, providing a low-resistance path that is superior to standard pressure plates. Its «Removable» design allows maintenance teams to replace a faulty I/O module in seconds without having to disconnect a single field wire, significantly reducing Mean Time to Repair (MTTR).
Installation Advice: Managing 36-Point Wiring Bundles
Wiring a 1756-TBCH can be challenging due to the high concentration of conductors in a small space. We recommend using 18 or 20 AWG wire with thin-walled insulation to ensure the bundle can fit comfortably within the RTB’s side-routing channels. Always use the provided housing cover to strain-relief the wires. It is a best practice to use wire markers on every conductor before inserting them into the 1756-TBCH; once the block is fully wired, troubleshooting a specific point becomes difficult without clear labels. Ensure the RTB is fully seated and the locking tabs are engaged before powering the chassis to prevent arcing on the module’s gold pins.
Maintenance and Hardware Durability
The 1756-TBCH is a robust mechanical component, but it should be inspected annually for screw tightness, especially in environments with high vibration or thermal cycling. Over-tightened screws can strip the threads, while loose screws can cause intermittent I/O signals or excessive heat buildup. If you are operating in a corrosive environment, check for oxidation on the copper clamps. The 1756-TBCH is designed for hundreds of insertion cycles, but the module-side pins should be checked for alignment if the block feels difficult to seat. Keeping a few spare 1756-TBCH units is highly recommended during new project startups, as they are the most common component damaged during aggressive wiring phases.
FAQs
Q: What is the difference between 1756-TBCH and 1756-TBS6H?
A: The TBCH uses cage clamp screws, while the TBS6H uses a spring-clamp mechanism for even faster wiring.
Q: Does the 1756-TBCH come with the I/O module?
A: No, Allen-Bradley terminal blocks are always sold separately from the I/O modules to allow engineers to choose their preferred termination style.
Do you need more references from this brand? Explore our full catalog of Allen-Bradley here.
This 36-pin cage-clamp removable terminal block is the standard interface for high-density I/O cards like the 1756-IA32.
