The Siemens 3VU2905-0B is a connecting cable designed specifically for the under-voltage and shunt release accessories on 3VU motor starter protectors. It bridges the release coil terminals to the control circuit, so the cable carries the trip signal from the remote pushbutton or safety relay back to the release mechanism inside the starter base.
What It Connects
This cable mates the under-voltage release (UVR) or shunt release (ST) coil on a 3VU motor starter protector to the control voltage source. The UVR drops out the starter when line voltage falls below a threshold; the shunt release trips on a remote command. Both are safety-related functions — the cable is part of the trip circuit, not the power path. Verify the release coil voltage rating on your specific 3VU unit before wiring.