U401-B Fuel Dispenser Solenoid Valve, AC 220 V

The U401-B is the electrically operated stop valve in a fuel dispenser's delivery path. It is normally closed and opens only while energised, so the dispenser's controller — not the operator's trigger — determines the measured quantity delivered.

Two coils operate the main and reduced-flow elements of a diaphragm valve — the manufacturer describes the main valve diaphragm as an imported special rubber. The main-flow coil passes the full rate; the reduced-flow coil passes a much smaller rate that the controller selects a short distance before the preset volume is reached. Closing at low velocity instead of full flow is what keeps the delivery from overshooting the set figure. Each coil draws 18 mA from an AC 220 V supply, and the two together consume 2 x 4 W.

Rated flow is 5 l/min minimum to 90 l/min maximum on the 1" body; the manufacturer also lists a 3/4" version at 65 l/min. Published working pressure is 0.035 MPa and the operating range is −40 to +70 °C, with seals in a special rubber rated to −40 °C.

State the dispenser's supply voltage, the port size and the flow rate required when ordering, and confirm the working-pressure figure against the maker's own datasheet — 0.035 MPa (0.35 bar) is published without qualification and reads as a minimum operating differential rather than a maximum line pressure.