Thermo Scientific Dionex ICS-2000, Operator'S Manual

Page: 60 / 390

ICS-2000 Ion Chromatography System
2-40
Doc. 031857-03 4/06
2.4.5 Injection Valve
The injection valve (P/N 057968) is a six-port, electrically-activated
valve. A 25-
µ
L sample loop (P/N 042857) is installed on the valve at the
factory.
The valve has two operating positions: Load and Inject (see Figure 2-20 ).
Eluent flows through either the Load or Inject path, depending on the
valve position.
•
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 automated sampler 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
column, carrying the contents of the sample loop with it.
Section 3.10
describes how to inject samples.
Figure 2-21 shows the injection valve connections. The injection valve is
plumbed at the factory with all tubing and fittings for connection to the
pump, injection port, column, and waste. A 25-
µ
L PEEK sample loop
(P/N 042857) is installed between ports L (1) and L (4). Dionex offers
Figure 2-20. Injection Valve Flow Schematics
To Waste
Sample In
To Column
From Pump
Sample
Loop
LOAD POSITION
To Waste
Sample In
From Pump
Sample
Loop
INJECT POSITION
To Column