iv
20.
A few drops of wetting agent should be added to the water in the sump tank to minimise
the effects of surface tension.
Note:
If too much wetting agent is added foaming will occur and it will be necessary to
replace the water.
A few drops of wetting agent may be introduced to the sight tube (level gauge), on the
side of the F1-10, via the overflow tube at the top. This will reduce the meniscus, making
readings clearer.
21.
Ensure that the stilling baffle is correctly positioned in the volumetric tank of the F1-10
such that the top edge is alongside the exit of the open channel in the moulded top.
22.
Close the flow control valve on the front of the F1-10 then connect the mains lead from
the F1-10 to the electrical supply.
23.
Switch on the RCD on the side of the F1-10, then press the TEST button to check that the
RCD is operating correctly. The RCD must trip. If the RCD does not trip or it trips before
pressing the test button then it must be checked by a competent electrician before the
equipment is used. Switch on the RCD again.
24.
Operate the pump ON/OFF switch and confirm that the pump functions. Slowly open the
flow control valve and check that water is delivered to the inlet end of the channel.
Allow the water to flow along the working section of the flow channel and discharge into
the volumetric tank of the F1-10. Allow circulation to occur for several minutes to
remove air from the system. Adjust the position of the F1-10 if necessary to minimise
splashing as the water discharges into the top of the F1-10.
25.
Release the actuator of the dump valve to close the valve in the bottom of the volumetric
tank. Fill the volumetric tank until water runs into the sump tank through the overflow.
Now check that the sight tube (level gauge) is full and no air bubbles are present. Repeat
this filling several times, ensuring that the sight tube is free from air bubbles.
26.
Close the flow control valve and allow water to drain from the volumetric tank until the
surface is level with the step in the bottom of the tank. A few drops of wetting agent
smeared onto the step will enable an accurate level to be achieved.
Slacken the securing screws at the top and bottom of the sight tube scale and position the
scale so that the meniscus of the fluid in the tube is level with the black datum line
engraved between the large and small scales. This will ensure that the scale is positioned
accurately for volumetric measurements using either of the ranges.
Note:
All volumetric readings should be taken with the stilling baffle installed, since
calibration has been effected in this condition.
27.
Place the stop logs in the slot at the discharge end of the channel to allow the channel to
fill with water to the maximum level.
Ensure that the flow control valve is closed, switch on the pump then slowly open the
flow control valve and allow the channel to fill with water. When the channel is full,
