8
Intended use
Connections of the ports at the positions
loading
and
injecting
Valve position
Loading (L)
In the valve position
loading
, the sample is filled into the sample
loop.
Valve position
Injecting (I)
In the valve position
injecting
, the sample is flushed for example
on a precolumn or main column for preseparation or separation.
The sample loop is filled, by injecting the sample at connection
1. This runs into the sample loop (connection 2 and 5) and
excessive sample is transported into the waste container
through connection 6.
Fig. 4
Valve positions loading and injecting
The eluent flows through the sample loop in opposite direction
during the injecting, see arrows in the figures.
Reed contact
The reed contact in the injection or multiposition valve gives the
start signal for a measurement to the entire analytical system
or a detector.
Hand-operated valves
For hand-operated valves, a mounting of a mounting plate or
a universal angle on the housing of a valve drive is advisable.
Electrical
valve drives
Electrical valve drives for the injection or multiposition valves
synchronize the sample injection in the analytical system. The
valves are operated by a 24 V direct current motor. The electri-
cal drive and the valve have been factory-set and can be modi-
fied by DIP switches (Dual In-line Package) on the bottom of the
device for certain applications.
By means of chromatography software or a cable for remote
control, certain positions can be controlled directly on a valve.
Delivery ex works
All valve drives are delivered with a ready-mounted injection
or multiposition valve.
Loading
Injecting
1
2
3
4
5
6
Waste
Pump
Column
Sample
1
2
3
4
5
6
Waste
Pump
Column
Sample
