Weller w 61 60w temperature controlled mains soldering iron weller t0056103399n the weller w61 is a 230v ac mains voltage temperature controlled soldering iron with an output of 60w making it suitable for medium and heavy electrical connections to transistors pcbs heavy duty connectors and sheet metalthe temperature of the iron is controlled by a built in magnastat thermostatic switch as magnets are heated their strength reduces and this principle is used to operate a spring loaded