Figure 12.
The panel a presents solenoid valve A connected through tubes B between two vertical reservoirs C. The reservoirs contain liquid, with a horizontal reference line crossing both reservoirs above the visible liquid level. The panel b presents the solenoid valve connected by tubing to the two reservoirs. One reservoir contains a higher liquid level than the other. The lower liquid level in the second reservoir appears within the marked region near its base.Performance of the solenoid valve during commissioning tests: (a) horizontal position resulting in pressure equalisation and (b) vertical orientation, showing no fluid transfer