Injection Valve With Sample Loop - Thermo Scientific Dionex Easion Operator's Manual

Pulse Damper
Flow output from the pressure transducer continues to the pulse damper,
which smooths minor pressure variations. From there, flow is directed to
the injection valve and then to the remainder of the chromatography
system.
2.3.3

Injection Valve with Sample Loop

The injection valve is a six-port, electrically-activated Rheodyne valve.
The valve has two operating positions: Load and Inject. Eluent flows
through either the Load or Inject path, depending on the valve position. A
10 L sample loop (P/N 042949) is installed on the valve at the factory.
Figure 2-6
LOAD POSITION
From Pump
To Column
•
In the Load position, sample is loaded into the sample loop, where it
is held until injection. Eluent flows from the pump, through the valve,
and to the column, bypassing the sample loop. Sample flows from the
syringe (or the Dionex AS-DV sample out line, if installed), through
the valve, and into the sample loop. Excess sample flows out to waste.
•
In the Inject position, sample is swept to the column for analysis.
Eluent flows from the pump, through the sample loop, and on to the
Doc. 155028-01 08/20
shows flow schematics for the valve.
Sample Loop
L
W
S
Sample In To Waste
= Sample
Figure 2-6. Injection Valve Flow Schematics
INJECT POSITION
From Pump
P
C
To Column Sample In
= Eluent
2 • Description
L
To Waste
19