Electrical Connections; Venting The Suction Pipe / Emptying The Residual Quantity; Overfill Protection - Ecolab CONNEXX Basic Manuel Technique

4.1.4

Electrical connections

See chapter
4.2

Venting the suction pipe / emptying the residual quantity

Apart from degassing of the product the lifting vessel offers two more advantages:
1. During commissioning and when changing containers, the suction line is automatically
and quickly vented, in other words filled with the product. The control unit does not give
the enable signal for the metering pumps until the level switch (see chapter 4.1, item 10)
in the lifting vessel has been reached.
2. The residual quantity in the container can be greatly reduced by means of an adjustable
delay time for the empty signal (see chapter 4.4.5). While the time runs, a product/air
mixture continues to be drawn from the container because the air valve (6) on the injector
(3) is open.
The enable signal for the metering pump(s) is interrupted after the first 5 seconds to
IMPORTANT
prevent any air from reaching the pump even at maximum delivery.
In order empty the residual quantity as well as possible, we also recommend tilting the
NOTE
container slightly with respect to the suction lance / Click & Plug coupling.
4.3

Overfill protection

The Connexx system is doubly protected against overfill of the lifting vessel.
Usually, the suction process is disconnected by the control unit. As soon as the float in the
lifting vessel is pressed upwards through the product flowing in, the solenoid valve shut and
interrupt the supply of compressed air to the injector.
The contact of the level switch is closed in an upward position. In the event of a cable
breakage the control recognizes product defects even if the lifting vessel is filled and starts
the suction process for the set time. So an alarm is set off or vessel change over to the
second one after the adjusted time has run out.
To prevent significant quantities of product from flowing through the injector into the exhaust
air area in the time following a cable breakage or solenoid valve malfunction, the suction
opening in the cap is sealed by a mechanical float. A small quantity of product may flow into
the exhaust air until it closes. Therefore it is absolutely necessary to install an air evacuation
duct (DN20) in a secured area (see chapter 4.1.3).
After trouble shooting and before restart the float has to be brought to the lower position
again. Therefore, the throttle has to be completely unscrewed. The position of the float can
be checked from the lateral suction opening. The float should then be released by the
equalisation of pressure.
If the float does not already fall due to its own weight you can, for instance, support this
NOTE
process by knocking with your finger on the flow control opening or with some
compressed air.
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4.4
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