7TB712.91

What is this terminal block used for?

It is a 12‑pin pluggable field-wiring terminal block used on compatible B&R System 2003 equipment to bring power and signal wiring (such as CAN bus connections and 24 VDC supply) onto the device in a neat, removable connector.

What type of connection does it use?

It uses spring (cage) clamp connections, allowing conductors to be secured without tightening screws and helping maintain consistent contact force over time.

How many pins and connection points does it have?

It is a 12‑pin terminal block, providing twelve separate connection points for field wiring.

What conductor size is it intended for?

It is specified as a 1.5 mm² class terminal block, intended for typical control-cabinet wiring sizes up to that range (depending on conductor type and any ferrules used).

Which B&R System 2003 devices commonly use this style of 12‑pin terminal block?

This 12‑pin TB712-style terminal block is commonly referenced for B&R System 2003 devices such as the EX270 CAN bus controller and certain Power Panel units (e.g., PP21/PP41 families) that require separate 12‑pin field terminal blocks. In these cases, the spring-clamp version is the B&R 7TB712.91.

Is the terminal block typically included with the module or panel?

Often, the compatible B&R System 2003 device is supplied without the 12‑pin field terminal block, and the correct TB712 terminal block is selected separately to match the preferred connection technology (spring clamp versus screw clamp).

How is CAN bus termination enabled when this terminal block is used with an EX270 CAN bus controller?

On the EX270, the controller has an internal bus termination resistor. To activate it, a bridge wire is fitted between the two dedicated termination pins on the 12‑pin terminal (pins 1 and 2).

What is the typical pin assignment when used on an EX270 CAN bus controller?

For the EX270, the 12 pins are used for termination activation, two CAN channel connections, shielding, and 24 VDC power. Typical assignment is: 1–2 termination bridge points, 3 CAN_H, 4 CAN_GND, 5 CAN_L, 6 shield, 7 CAN_H, 8 CAN_GND, 9 CAN_L, 10 shield, 11 +24 VDC, 12 GND.

Can it be used to loop the CAN bus through the node as well as connect the node to the network?

Yes. On the EX270 connection concept, two electrically isolated CAN interfaces are presented at the terminal, and the connections are arranged so the CAN wiring can be continued through the node, simplifying network integration.

What is the main difference between spring-clamp and screw-clamp versions of this terminal block style?

Spring-clamp versions use a spring mechanism to hold the conductor, which can speed up wiring and reduce variability from tightening torque. Screw-clamp versions rely on a screw to clamp the conductor, which some users prefer for certain wiring practices and conductor types.

Are there any recommended accessories used with this terminal block style?

Depending on the installation and the connected device, retaining clips and shielding-related accessories may be used alongside TB712-style terminal blocks to improve cable management and strain relief within a control cabinet.