Part identity and fit
The Schneider Electric TeSys WB1HA054 is a low-consumption contactor coil, AC/DC control circuit, rated 55 V AC 50 Hz / 60 V AC 60 Hz. It is the replacement coil for CV1B and CV3B contactors in the TeSys range.
This coil is marked obsolete by the manufacturer. No need to gut the whole line if you can secure a few of these; just be aware that the supply window is closing.
The 55 V AC 50 Hz / 60 V AC 60 Hz rating means this coil pulls in reliably on a 55 V control transformer at 50 Hz, or a 60 V tap at 60 Hz — common in legacy European and North American control circuits. The low-consumption design keeps the control transformer sizing modest and reduces heat in the panel.