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Product information
4000 MiD® Instructions, V6695
5.8.2 The Direct Flow Interface (DFI) – optional
The DFI can be used to directly infuse samples from a syringe pump and
couple the MiD to a nano-flow LC system. KNAUER recommends a flow
rate range of 200 – 2000 nL/min to the spraychip 200.
The DFI consists of two conductive unions connected by a 50 mm length
of 25 µm ID PEEK tubing. The DFI is designed to accept 1/32” OD PEEK
tubing as the input line.
Fig. 14
The Direct Flow Interface (DFI)
To assemble the spraychip to the main body of the DFI use the same pro-
cedure as detailed for the SFI (see section 5.8.1 on page 23).
5.8.3 Installing spraychip assemblies
The DFI and SFI assemblies can both be fitted to the MiD using the pro-
cedure which is detailed below.
1.
Ensure the door is open at 90˚.
2.
Before fitting a spraychip assembly to the MiD a nitrogen flush of the
interface must be initialised. Open the software and click the nitro-
gen flush button, after a few seconds a flow of nitrogen gas should
be audible.
3.
Align the DFI/SFI and spraychip 200 with the opening in the vac-chip
assembly.
4.
Gently slide the DFI/SFI into the assembly until the PEEK screw rea-
ches the threaded section of the vac-chip assembly. Take care during
insertion that the spraychip 200 does not collide with the metalwork.
5.
Screw the PEEK collar into the assembly until finger tight.
Note:
If there is any excessive resistance when tightening the screw, stop
and repeat steps 3-5.
6.
Connect the high-voltage connector from the DFI/SFI to the
high-voltage output located at the front of the MID, see Fig. 15.
7.
Close the door of the front cover.
Note:
Ensure the PEEK tubing lines from the DFI/SFI are fed
through the cut-outs in the door, see Fig. 15.
Grub screw
Input line
spraychip 200
PEEK screw
Main body
Metal collar
Procedure
