The Schneider Electric WB1KB138 is a replacement coil from the TeSys range, designed for contactors that accept the WB1-K coil platform. It is a low-consumption AC coil rated for 415...440 V AC at 50...400 Hz, with control circuit voltage limits of 319...405 V across that same frequency band. The coil draws 380...520 W inrush (450...620 VA) and holds at just 0.15...0.2 W (0.15...0.2 VA), which keeps the thermal load on the control transformer low during continuous operation. Sealed operating time is 25 ms, and mechanical durability is rated at 1,200,000 cycles. Maximum operating rate is 120 cycles per minute at 131 °F (55 °C). The coil's average resistance is 257 ohms at 68 °F (20 °C).
Any integrator or panel builder with a legacy TeSys contactor needing this coil should verify the contactor frame accepts the WB1-K coil platform.
The 415...440 V AC control voltage is non-standard for most modern panels. This coil is for legacy installations where the control circuit operates at that higher voltage range. The low-consumption hold-in power (0.15...0.2 W) means the coil stays cool in continuous duty, which extends the life of the contactor assembly and reduces heat buildup inside a sealed enclosure. The 1,200,000 mechanical cycles are typical for a contactor coil in this class — suitable for applications with moderate switching frequency, not high-speed cycling.