Gow-Mac 400 Series, Operating Manual

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27 Series 400 / 402 Gas Chromatograph Operating Manual GOW-MAC Instrument Co.
May 2017, Rev. 7
THESE SHOULD NOT BE EXCEEDED! For longer fi lament life and a stable
baseline, lower fi lament temperatures are recommended. Recommended starting
bridge setting is 100mA for helium carrier gas.
Example: A setting of 200 on the DET. TEMP. CONTROL results in an operating
temperature of 200 °C, thus maximum bridge current when using helium at
this temperature is 240 mA. When maximum sensitivity is not required,
the current should be reduced to 100 mA.
Chart 4-1
0
100
200 300 400
500
0
100
200
300
Bridge Current mA
Cell Temperature °C
W, WX, W2, W2X, AuW, AuW2, Ni, Ni2 Type Filaments
Oxygen -
Argon
Nitrogen
Helium
"Maximum" Line —
Find your carrier
gas and do not
go above the line
when setting mA
and temperature
7. After 20-30 minutes, press the SELECTOR BUTTON for BRIDGE CURRENT .
8. Turn the DETECTOR CURRENT SWITCH to ON .
9. Adjust the BRIDGE CURRENT CONTROL to the desired setting (refer to
CHART 4-1).
NOTE
&
IF BRIDGE CURRENT DOES NOT RESPOND, CHECK
CARRIER GAS PRESSURE. THE FILAMENT PROTECTOR
SWITCH MUST HAVE 15-20 PSIG TO OPERATE.
After approximately 45-60 minutes, the instrument should be up to temperature and ready
for the injection of samples. During the warm-up period, recording devices should be
zeroed.
4.3 Strip Chart Recorder
The Series 400 GC is suitable for use with almost any strip chart recorder of the
potentiometric type (1 mV, 10 mV, or other). For best results and maximum sensitivity, the
0 - 1 mV is recommended. An adjustable chart drive is also recommended: 1/4, 1/2, 1,
2 in/min.
A. Connect the recorder to the GC.