What the COM060 module does in the panel
The Siemens SENTRON 3VA9187-0TB10 COM060 communication module is an accessory that snaps into the right switch pocket of a 3VA2 100/160/250 molded-case circuit breaker, adding digital communication and measurement capability. It draws a maximum of 0.1 A from the breaker's internal supply, dissipating 2.4 W. The module communicates with the electronic trip unit and with residual-current equipment, and it detects the breaker's switch position — On, Off, or Tripped — so the control system knows the state of the load circuit without a separate auxiliary contact block.
Communication bus and topology
The module connects to the circuit-breaker communication system via a single interface, wired as a spur line through a T feeder. The total bus length for the communication system is 20 m, which sets the maximum distance from the last module to the COM800 gateway or host controller. Four slots are available on the module for function modules, allowing expansion of communication protocols or I/O capability. The COM060 itself handles data exchange with the electronic trip unit, so the host sees real-time current, energy, and trip-event data.
Environmental and protection ratings
The module is rated operating resource protection class III according to IEC 61558, meaning it must be supplied from a safety extra-low voltage (SELV) source.