Chemtrac HydroAct 4, User Manual

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46 Chapter 3. Sensors
Flush Signal
Allows an external flush signal to be associated with a specific sensor. The flush signal
will notify the sensor that an automatic cleaning operation is underway. Options are “Disabled” or
selectable from a list of available digital inputs.
Process Signal Allows an external process signal to be associated with a specific sensor and allows
the external signal to enable or disable a sensor. Options are “Disabled” or selectable from a list
of available digital inputs.
Hold Delay The Sensor hold delay is used following a flush event to allow the sensor reading to
recover. Time entered in HH:MM:SS format.
3.1.5.2 Sample Setup
Options → Setup → Sample Setup
Period The number of seconds over which a measurement is made. Range of values available 4 to
998 seconds. Please note that the “Period” must be less than or equal to the “Frequency”.
Frequency The number of seconds between measurements. Range of values available 5 to 999
seconds. Please note that the “Frequency” must be greater than or equal to “Period”.
Flow Rate Value can be changed from the factory default setting of 75ml/min to match the actual flow
rate through the sensor in order to achieve accurate count/ml or count/100ml readings.
Particle sizing may not be accurate if the unit has not been calibrated at the flow rate being
used. It is recommended to leave the flow rate at 75 ml/min unless changes to this setting
have been previously discussed with Chemtrac.
Units Options are “Raw”, “per ml” or “per 100 ml”. If “Raw” is selected, the particle count data will
represent all particles that passed through the sensor during the sample period. The data will
not be normalized to a particular volume. If “per ml” is selected, the particle count data will be
normalized to the average number of particles per ml of sample. If “per 100 ml” is selected, the
particle count data will be normalized to the average number of particles per 100 ml or sample.
This setting can be particularly useful when analyzing very clean samples.
Advanced Setup Composite of Differential. This allows the user to choose between using Composite
or Differential Size Range settings. Composite size ranges can not overlap. In “Composite” mode,
if 5
µ
m is the “To” value in Bin 1 then it must also be the “From” Value in Bin 2. In “Differential”
mode the bins can overlap.
3.1.5.3 Size Ranges
To set the size ranges the PC6 Particle Counter allocates individual particles to, select:
Options
→
Setup
→
Size Ranges