BKxx50 and BKxx51

The Bus Couplers / Bus Terminal Controllers require an operating voltage of 24 VDC. Use a 4 A fuse or a Class 2 power supply to comply with the UL requirements.

The connection is made by means of the upper spring-loaded terminals labelled Us and GNDs. This supply voltage is used for the electronic components of the Bus Coupler and Bus Terminal Controllers and (via the K-bus) the electronic components of the Bus Terminals. It is galvanically separated from the field level voltage.

BKxx50 and BKxx51 1:
Power supply connections for BKxx50 and BKxx51
BKxx50 and BKxx51 2:
UL identification

CAUTION

BKxx50 and BKxx51 3:

Note the UL requirements for the power supply.

To comply with the UL requirements, the 24 VDC supply voltage for Us must originate

    • from an isolated source protected by a fuse of max. 4A (according to UL248) or
    • from a voltage supply complying with NEC class 2.
      An NEC class 2 voltage source must not be connected in series or parallel with another NEC class 2 voltage source!

    CAUTION

    BKxx50 and BKxx51 4:

    No unlimited voltage sources!

    To comply with the UL requirements, Us must not be connected with unlimited voltage sources.