Where the class gets used
The 1SBL183001R8110: Electrical contactors in this line are the switched element in a motor starter or heater/lighting bank — coil energises, power contacts close, the downstream load is commanded by the control circuit upstream of the contactor. In a panel layout this part sits between the short-circuit protection and the overload relay, so the wireman runs line-side conductors into the top terminals and load-side conductors out the bottom, with the coil terminal block taking a separate control-voltage feed.
Sourcing posture
Sourcing is run against an RFQ for the BOM line, with the order code 1SBL183001R8110 specified into the build sheet.