Asco pressure switch P303/T01 3 phase 20A

The P303T01 a more lightweight 3 phase pressure switch then the Asco P302/6 3 phase pressure switch. The difference is also that the P302/6 has a partially metal cover. And the P303T01 has a full plastic cover.

This pressure switch has been used espresso machines like: Bianchi, Fiamma and Orchestrale.Nowadays these pressure switches are named Asco, in the past the company name was Sirai but the product remains the same.

The P302/6 20A is a slightly lighter pressure switch. The pressure of this switch can be adjusted from 0,5 to 1,4 bar. The max fluid temperature is 140 °C. with a max contact load of 20A

The connection for the pressure is a ¼” BSP-G with a pipe 4x6 mm

The principle of a spring actuated pressure switch is that when the boiler pressure raises, a membrane goes up and when it reaches the set pressure the contacts will disconnect. This results that there goes no power to the heating element anymore. When the pressure in the boiler lowers the contacts will connect again and the heating procedure starts over again.

For more information about the working of pressure switches, go to our blog page and you will find a article about pressure switches.