Pressure Switches

Finally tested and compared old and new sensors.

NEW Spec - 3rd P-switch. ON 33psi, Off 23psi.
OLD Value - 3rd P-switch. ON 37psi, Off 31psi.

NEW Spec - 4th P-switch. ON 27psi, Off 17psi
OLD Value - 4th P-switch. ON 31psi, Off 25psi.
The old 4th P-switch is almost at the 3rd switch value. Both have half the new switch "on to off" PSI spread.

The Sensor has a membrane sealing the oil from the switch assembly. The switch comprises a small flexed disk that sits against the membrane. When oil pressure is applied against the membrane it flexes the disk.

The disk pops in at the design pressure thereby completing the circuit between the casing and the centre contact. This is not a sophisticated design when compared to some units used in late industrial applications however those can cost upwards of $500 a unit.

The pictures show both sides of the flex disk (small round disk) and the last is the flex disk installed over the switch contact pin.