EST Encon Evolution, User Manual

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Final Hold Time (min) – This is not a programmable setting but a function of the
set conditions. The final hold time will be the difference of the final purge time
from the sum of the initial time and the time needed to achieve the final flow rate.
For Example: Total Purge Time = 4 minutes
Initial Flow = 40ml/min
Initial Hold Time = 0.5 minutes
Ramp Rate = 40ml/min per minute
Final Flow = 200ml/min
The Final Hold time at 200ml/min would be 0.5 minutes.
Explanation: It takes 4 minutes to ramp from 40ml/min to 200ml/min at a
rate of 40ml/min per minute. The final hold time is calculated to be 0.5
minutes.
4 minutes – (0.5 m 3 minutes) = 0.5 minutes
Purge Time (min) – This is the length of time for the sample purge. The purge time can
programmed from 0.0 to 999.9 minutes.
Trap Dry Purge Temperature ( ° C) – This is the temperature of the adsorbent trap
during dry purge. The temperature can be programmed from 25°C to the set point in 1°C
increments.
NOTE: This temperature should be set to below ambient to eliminate the possibility
of analyte migration within the trap prior to desorb.
Dry Purge Flow Rate (ml/min) – This is the rate the pressurization gas flows through
the adsorbent trap during the dry purge process. The Dry Purge Flow Rate can be
programmed from 1 to 500ml/min in 1ml/min increments.
Programmable Dry Purge Flow Control - <click> the Program button to enable this
feature. This feature can be used to change dry purge flow rates during the dry purge
cycle. The screen as shown in Figure 3j will appear. Check the
Enable Ramp Control
box to program the desired settings.
Initial Flow (ml/min) – This is the beginning dry purge flow rate programmed in
ml/min. The initial flow can be programmed from 0 to 500ml/min in 1ml/min
increments.
Initial Hold Time (min) – This is the time in minutes the initial flow is
maintained. The initial hold time can be programmed from 0.0 to 999.9 minutes.
Ramp Rate ((ml/min)/min) – This is the rate programmed in ml/min per minute
the dry purge flow will increase after the initial hold time has expired to the
desired final flow set point. The ramp rate can be programmed from 1ml/min to
500ml/min in 1ml/min per minute increments.