PerkinElmer TORION T-9, Руководство пользователя

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Gas Chromatograph . 149
•
End hold time is the time that the column temperature remains at the End
temperature
until the end of the run. Typically this time is set to 10 seconds.
•
Pre injection pressure offset controls the pressure differential from the default
pressure that is programmed into the Torion T-9 GC/MS. All of the Torion T-9 GC/MS
instruments are pre-calibrated so that the retention times of the compounds are
consistent. The starting pressure is slightly different on each Torion T-9 GC/MS. During
some types of injection the operator may want the pressure to be different prior to
sample introduction and then to revert to the default starting pressure during sample
analysis. This allows the pressure to be set to a plus or minus offset during pre-injection
conditions.
NOTE: Pre-injection conditions are set and held during the time after the start button on the Torion T-9
GC/MS has been pressed and before an injection is made. These conditions are maintained for 1
minute. If a sample has not been injected before 1 minute then the system resets to the conditions
outside of the injection routine. The split valves are held in the off position to conserve helium
carrier. If the pre-injection boxes are checked then the valves will open during the pre-injection
state.
Split Injection
The Split Injection section is used for controlling the GC inlet’s split injection controls.
Normal operation is to run with the split values open.
NOTE: To introduce more sample into the GC column the valves should both be closed for 1 to 2 seconds.
To do this you would set the Split On time to 2 seconds, telling the instrument to turn the split on at
2 seconds, this will keep the valve closed after the sample is injected for 2 seconds then it will open
to sweep the injector. Turning the split on for longer times will have a detrimental effect on the peak
shape of early eluting peaks. Later eluting peaks will refocus at the head of the column so they will
not be as adversely affected.
• The
10:1 Split On
opens the lower flow split valve at the defined time. Normal setting
is to turn on the split at time 0.
•
The 10:1 Split Off closes the lower flow split valve at the defined time. Normal setting
is to turn off the split at 10 seconds.
•
The 50:1 Split On opens the higher flow split valve at the defined time. Normal setting
is to turn off the split at 10 seconds.
• The 50:1 Split Off closes the higher flow split valve at the defined time. Normal is to
turnoff the split at 30 seconds.
• Pre injection 10:1 and Pre injection 50:1 are used during the pre-injection state.
NOTE: Pre-injection conditions are set and held during the time after the start button on the Torion T-9
GC/MS has been pressed and before an injection is made. These conditions are maintained for 1
minute. If a sample has not been injected before 1 minute then the system resets to the conditions
outside of the injection routine. The split valves are held in the off position to conserve helium
carrier. If the pre-injection boxes are checked then the valves will open during the pre-injection
state.