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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B. Turn the strip chart recorder ON .
C. Adjust the GC ATTENUATOR to infi nity (

).
D. Adjust the RECORDER ZERO KNOB to position the pen to the desired baseline on the
strip chart usually 5 to 10 small divisions on the chart paper). Where positive and negative
peaks are expected, the pen may be set mid-scale. If the pen response is slow, the
recorder may require adjustment (Refer to the recorder operating manual).
E. Set the GC ATTENUATOR to the "64".
F. Adjust the GC ZERO CONTROL to reposition the pen to the same spot located in Step D
above. When zeroed, the attenuator may be switched to any setting and the pen should
not move. The
POLARITY SWITCH should be set so that the drift due to GC warm-up is
upscale. In this manner, the extent of drift and the leveling out of the baseline may be
observed.
Baseline drift may continue if the oven or ambient temperature continues to change (2 to
4 hours). Let the GC warm up a little longer. If drift continues after 5 to 6 hours, check for
leaks in the system.
G. Refer to the recorder manual for correct chart speeds, warm-up times, etc.
4.4 Computer Integrator Zeroing
The Series 400 GC may also be used with commercially available computing integrators.
After the integrator is properly connected to the instrument, it may be turned "ON". At this time
the electrical or recorder zero should be established and reference should be made to the
integrator operating manual for further operating instructions.
4.5 Chromatography Data Software
The Series 400 GC may also be used with most commercially available chromatography data
software.
GOW-MAC off ers a chromatography data software program called "DACS". This software
enables the customer to directly control the data coming from the GC on a personal computer.
If DACS is being used in conjunction with the Series 400, follow the setup instructions that
come with the software.
4.6 Sampling Procedure
Once the instrument has been brought to the desired temperatures and the recording device
has been lined out, the following many be done:
A. Change the GC ATTENUATOR to a setting of "8", then "4", etc. until a straight-line
trace is obtained at the selected temperature.
B.
INJECT
the sample.