Gow-Mac 400 Series, Operating Manual

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GOW-MAC Instrument Co. Series 400 / 402 Gas Chromatograph Operating Manual
May 2017, Rev. 7
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C. GC POWER SWITCH "ON" .
D. INJECTION PORT TEMPERATURE CONTROL to 130-135 °C (10-15 °C higher than
the column oven temperature).
E. COLUMN TEMPERATURE CONTROL to 120 °C.
F. DETECTOR TEMPERATURE CONTROL to 130-135 °C (10-15 °C higher than the
column oven temperature).
WARNING
!
THE DETECTOR MUST BE KEPT APPROXIMATELY 10-15 °C
HIGHER THAN THE COLUMN OVEN TEMPERATURE TO AVOID
CONDENSATION AND CONTAMINATION OF THE TCD.
G. Allow the GC to come to temperature, about 40 minutes.
H. After the GC has warmed up, press the SELECTOR Button for BRIDGE CURRENT .
I. Turn the DETECTOR CURRENT SWITCH to ON .
J. Adjust the CURRENT CONTROL to 100 mA.
K. Turn the recorder ON .
L. Zero the recorder (Chapter 4). If a peak goes off scale, the ATTENUATOR should be
turned to a position that brings the peak back on scale.
M. Set POLARITY SWITCH for an upscale drift.
8.5 Procedure
A. Temperatures required for this experiment are 130 °C on the DETECTOR and 120 °C
on the COLUMNS. The INJECTION PORT TEMPERATURE should be approximately
10-15 °C higher than the column temperature.
B. Set the POLARITY SWITCH to the Carbowax column. Put the ATTENUATOR on
"1". When the temperatures have reached the desired settings and the baseline of the
recorder has lined out you are ready to make an injection.
C. Draw a 1 μL SAMPLE into the syringe and then draw about 5 μL of air. With the
recorder running (1"/min. or faster), inject the sample onto the Carbowax column.