Farnell Instruction Leaflet 6101-0018 Farnell Ref: 427-6565 Operating instructions Electrical connections by 250 (1/4) push-on connectors. 1 Common 2 N.C. opens on pressure rise 3 N.O. closes on pressure rise The switch is factory set to operate within +/- 0.1 PSI at 1 PSI on rising pressure. Pressure connection Straight Tube for 1/8 ID Tubing or Gasket or O-Ring. Pressure range Four springs are supplied with the switch, colour coded and offering the following ranges: *INSTALLED SPRING 1.0-4.0 P.S.I. RED 3.0-10.0 P.S.I. DARK BLUE 9.0-20.0 P.S.I. SPRING KIT YELLOW 19.0-40.0 P.S.I. 49-0003-A-00 *fitted as standard Adjustment of the setpoint is provided by an adjustment screw and compression spring, acting against the force of the diaphragm. Media pressure acting against the diaphragm causes the pressure disc to push up against the operator button of the microswitch. The disc has a stop to prevent overtravel of the operator button of the microswitch. Because of the snap action, of the microswitch, the switches do have a deadband or hysterisis which most designers utilise in their logic circuit. Before attempting to change the pressure spring, disconnect the electrical supply from the microswitch and pressure hose from the pressure port. To change the pressure range spring, unscrew the pressure adjustment screw and withdraw only the operating spring from the body. If the operating pin is also removed, replace it before replacing the spring. Select the new spring and insert into the switch and replace the adjustment screw.Technical specification Pressure range: 1.5 IN H2O to 45 psig (using four springs) Electrical: SPDT(N/O or N/C) Contact Rating 5 Amp, 250Vac Fluid Medium Wide range of media Burst pressure 45 psig 6 Mechanical Life 1.0x10 cycles o Operating temp -40 to 85 C Contacts Silver alloy Diaphragm Polyurethane Case material Glass filled polyester Weight 18 grams