Gow-Mac 400 Series, Operating Manual

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29 Series 400 / 402 Gas Chromatograph Operating Manual GOW-MAC Instrument Co.
May 2017, Rev. 7
C. Observe the chromatograms for peak separations, peak heights, and retention times.
Adjust controls accordingly.
4.7 Standby and Overnight Conditions
When the GC is used intermittently during the day or is needed right away the next morning, it
is recommended that the GC be kept in "standby" condition. This keeps the instrument ready
to use without waiting for a long equilibration period. Proceed as follows:
A. Push the SET Button and DETECTOR Button "IN".
B. Turn DETECTOR CURRENT CONTROL counterclockwise (CCW) until the DIGITAL
PANEL METER displays between 28 to 40. Then turn CURRENT SWITCH to "off '
position.
C. Reduce the carrier gas fl ow from 40 psig to 20 psig to save gas consumption (FLOW
RATE MUST NOT FALL BELOW 20 psig).
4.8 Shutdown Procedure
The following sequence of steps should be followed in the given sequence to insure proper
cool-down of your GC and longer life of the detector fi laments.
A. Push the SET and DETECTOR CURRENT Buttons "IN".
B. Turn the DETECTOR CURRENT CONTROL counterclockwise until the DIGITAL PANEL
METER displays between 28 to 40. Then turn the CURRENT SWITCH to "off " position.
C. Repeat Steps A & B above for the COLUMN, DETECTOR , and INJECTOR .
D. Let the GC cool down for 30 minutes. For quicker oven cool down, the column oven lid
may be lifted and left open.
E. Let the GC cool down until the detector temperature reaches 90 °C. The fi laments
may burn out if the instrument is not left to cool properly.
WARNING
!
IF THE INSTRUMENT IS NOT LEFT TO COOL PROPERLY,
THE DETECTOR FILAMENTS MAY BURN OUT (OXIDIZE).
F. Elute all samples from the column BEFORE the columns cool down.
G. Shut ac power OFF .
H. Turn helium or other carrier gas "OFF".