Teledyne 6712FR manual Flow Proportional Sample Volumes

6712FR Refrigerated Sampler Section 5 Extended Programming

5.11Flow Proportional Sample Volumes

The 6712 can collect flow proportional sample volumes. For some sampling protocols, these flow-weighted, variable-volume samples can be more representative of the stream. This is because stream characteristics often change as the flow fluc- tuates.

Variable-volume sampling is possible when the sampler is pro- grammed for Uniform Time pacing. To enable this feature, select YES at the display asking “DO YOU WANT SAMPLE VOLUMES DEPENDENT ON FLOW?”

DO YOU WANT

SAMPLE VOLUMES

DEPENDENT ON FLOW?

YES NO

After answering YES, the sampler displays screens to program the flow proportional volumes. If the sampler has a 700 Series Flow Module inserted, you will be asked which flow mea- surement should be used to determine the volumes.

FLOW PULSES

FLOW MODULE VOLUME

To base the volumes on an external flow measurement device attached to the Flow Meter connector, select FLOW PULSES. To base the volumes on the 700 Series Flow Module readings, select

FLOW MODULE VOLUME.

Next, the sampler asks for the SAMPLE VOLUME to collect at each time interval. This volume is expressed as 10 ml for every X number of pulses, or if using a flow module, for every volume unit.

SAMPLE VOLUME: 10 ml FOR EVERY

___ PULSES

Refer to section 5.11.1, Calculating Variable Sample Volume Set- tings, for a more detailed discussion on this setting.

The final screen used to program variable-volume sampling is the MINIMUM SAMPLE VOLUME. If the number of flow pulses or flow module volume is not sufficient enough to collect this minimum volume, the sample is skipped and the flow count carries over to the next sample time. This setting ranges from 10 ml to a maximum determined by the bottle volume.

MINIMUM

SAMPLE VOLUME

___ ml

(10 - maximum)

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