4.
Put the stillwell assembly into the enclosure. It stands on the enclosure
floor at the back. Clamp the stillwell to the bracket with the stainless
steel hose clamp supplied.
5.3.1
Connect The Stillwell To The Pan
A flexible hose is used to link the stillwell to the evaporation pan. It is
normally buried to protect it from accidental damage. This hose ensures that
the water level in the pan and stillwell are the same at all times.
An air lock could form in the hose if there are any high points. This can
restrict or block water transfer and prevent the system from operating
correctly.
To keep the hose straight, sleeve it with a piece of 40mm PVC pipe before it
is buried. This also serves as a duct for the fill hose and the drain pump cable.
Lay the sleeved hose into a shallow trench between the stillwell and pan. Cut
the hose to length and connect it to the pan, using a hose clamp.
Automatic Evaporation System
INSTALLING THE EQUIPMENT 21
Stillwell
6541-31/C (can be
rotated 90° on
stillwell)
m12.5 hose to
evaporation pan
Stillwell mounting
bracket and battery
shelf
Enclosure
SS hose clamp
5.3.2
Fill The Pan And Set The Water Level Instrument
Fill the pan with water to near the reference point in the pan level gauge.
Check the hose connections and the pan for leaks and fix any problems.
Confirm that the water level in the stillwell is the same as in the evaporation
pan, and that they move together. An airlock in the hose system can prevent
this happening. To check, take some water from the pan and almost fill the
stillwell. Check that it drains back to the previous level. If it doesn’t, clear the
air lock.
To clear an airlock, remove the hose from the level gauge and blow through it
until it bubbles into the stillwell. Replace the hose and confirm the water
transfer is OK.
5.3.3
Prepare The Float System And Stillwell Assembly
Do the following:
1.
Bolt the Model 6541-31/C instrument to the stillwell cap, with the two
bolts provided. The instrument must be fitted with a
100mm-circumference float pulley and an offset pulley.
2.
Prepare the float system. This is normally supplied as an assembly, ready
for installation. However, if you need to prepare it yourself, follow these
steps:
- Loop one end of the floatline through the eye of the float. Use two
crimps to fix the loop.
- Place the float in the bottom of the stillwell. Thread the floatline up
through the centre hole in the stillwell cap. Place the cap and instrument
in position on the stillwell.
UNIDATA
22 INSTALLING THE EQUIPMENT
