Armfield PCT40 - Exercise H - Manual Operation of Normally Closed Solenoid Valve

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Exercise H - Manual operation of Normally Closed
solenoid valve
Objective
To manually maintain the level in a process vessel using a Normally Closed solenoid
valve to control outflow rate from the vessel.
Overview
Outflow from the large process vessel is directed through a Normally Closed solenoid
valve. By manually switching this valve on or off via the computer, the valve is
opened or closed and outflow from the vessel can be controlled in order to balance
the inflow to the vessel and maintain the fluid level at a set point value.
Equipment Required
PCT40 bench with large process vessel, inner cylinder and supplied flexible tubing.
Equipment set up
Ensure that the apparatus has been set up according to the Installation section.
Ensure that the inlet connector for the apparatus (on the right of the plinth behind the
pressure regulator) is connected to a suitable mains water supply. Check that the
central cylinder is securely in position inside large process vessel. Using a suitable
length of tubing, connect the self-sealing connection socket on the base of the large
process vessel to the quick release connection on the valve SOL1 at the front right of
the plinth.
The drain valve at the end of the plinth should be directed to a drain and left open.
Solenoid valves 2 and 3 should be connected to a suitable drain using the tubing
supplied. The drain valve in the base of the large process vessel should also be
connected directly to drain using flexible tubing.
Connect the apparatus to a suitable PC on which the software has been installed
using the pale grey USB cable supplied. The flat connector on the cable connects to
the PC, usually via a socket at the back. The other end connects to the socket on the
orange panel on the front of the plinth. Check that the PC is working and switched
on.
Procedure
Switch on mains power to the console and run the PCT40 software. Select ‘Section
3: Level Control (outflow)’.
In the PCT40 software, set the PSV to operate at 75%. Refer to the flow meter
display and adjust the PSV setting to give a flow rate of 1 L/min using the arrow keys.
Check that the level reading L1 is varying with the rising water levels.
Partially close the drain valve at the base of the large process vessel to produce a
constant low outflow to drain.
From the Sample menu, select ‘Configure...’ and set the software to Automatic
sampling with a sample interval of ten seconds and a Continuous duration.
Select the
icon to begin data logging.