INTRINSICALLY SAFE CONTACT SWITCH / TILT SWITCH CONTROLLER (STS) ALLOWS SAFE OPERATION OF TILT SWITCH PROBES IN HAZARDOUS ENVIRONMENTS. PROVIDES ALARM INDICATION IN VISUAL OR RELAY FORM. ISCS IS FM & CSA APPROVED FOR CLASS I, DIV 1 GROUP A,B,C,& D & CLASS II DIV 1 GROUP E,F & G WHEN USED WITH A TSP OR OTHER DRY CONTACT SWITCH. STS IS FM & CSA APPROVED FOR CLASS I, DIV 1 GROUP A,B,C & D & CLASS II DIV 1 GROUP E,F & G WHEN USED WITH AN STS PROBE.