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15 servicing the detector, 16 rinsing the sample path – Metrohm 940 Professional IC Vario ONE/SeS/PP/Prep 3 User Manual

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5 Operation and maintenance

940 Professional IC Vario ONE/SeS/PP/Prep 3 (2.940.1530)

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2 Regenerating the adsorber material

Allow the depleted adsorber material to dry overnight in an oven at
140 °C. The dried adsorber material once again has the original color
and can be reused.

Two H

2

O adsorption cartridges are provided so that the H

2

O adsorption

cartridge can continue to work without interruption.

5.15

Servicing the detector

Follow the maintenance instructions in the the detector's manual.

5.16

Rinsing the sample path

Before a new sample is measured, the sample path has to be rinsed with it
long enough to prevent the measuring result from being falsified by the
previous sample (sample carry-over).

The time required to rinse the sample path with the new sample is called
the rinsing time. The rinsing time depends on the transfer time.

The transfer time corresponds to the time the sample needs to flow from
the sample vessel to the end of the sample loop. The transfer time
depends on the following factors:

The pump capacity of the peristaltic pump or Dosino

The total capillary volume

The volume of the gas removed from the sample by the sample degas-
ser

The transfer time can be determined as follows:

Determining the transfer time

1 Emptying the sample path

Pump air through the sample path (pump tubing, tubing connec-
tions, capillary in the degasser, sample loop) for several minutes until
all liquid is displaced by the air.

2 Aspirating the sample and measuring the time

Aspirate a sample typical for the later application and use a stop-
watch to measure the time the sample needs to go from the sample
vessel to the end of the sample loop.