Ecolab Elados EMP IV E00 Notice Technique page 41

For metering in pipelines with underpressure, a pressure control valve
must be built into the metering pipe.
NOTE
To prevent the running out of the metering medium when the pump is
stopped, we also recommend the fitting of a solenoid valve which is
approved for use with the pump.
Pos. Description
1 Injector valve (Metering valve)
2 External release
3 Solenoid valve
4
Pressure control valve
The metering point should not be positioned
below the discharge container as this
arrangement creates a risk of the discharge
container being siphoned empty (see fig. 6.4).
The metering point should not be positioned
below the discharge container as this
arrangement creates a risk of the discharge
container being siphoned empty (see fig. 6.5).
Pos. Description
1 Overflow valve
2
Injector valve (Metering valve)
3
Pressure control valve
When using long metering lines or in the case of an inflexible pipe work, a
pulsation attenuator (pos. 1) should be installed in the pressure line
(directly behind the pressure valve of the metering pump) in order to avoid
pressure strokes.
The suction pipes must be kept as short as possible.
Long and twisted suction pipes may lead to air buildup in the
system.
The max. suction height is 2 m and the max. flow velocity is 0.3 m/s!
(see also chapter
Always lay the suction pipe so that it ascends to the suction valve of
the metering pump.
For system designs with a suction tube length of more than about
3 m and/or that must reach a suction height of > 2 m, an appropriate
lifting vessel must be installed to support the suction process.
The lifting vessel must be positioned above the pump.
Pos. Description
1 Lifting vessel
2 Solenoid valve
417101090_EMP_IV_E00_E10
A pressure control valve or a metering valve is not an
absolutely hermetically sealing shutoff device.
11 "Technical Specifications").
Fig. 6.4
- 41 -
Fig. 6.5
Fig. 6.6
Fig. 6.7
Fig. 6.8
Fig. 6.9
Rev. 8-06.13
Fig. 6.3