Hach Sigma 1600, Инструкция по эксплуатации инструмента

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Page 26
Sampler Programming Options
6507programming.fm
Section 3
3.2.2 Flow Proportional Mode
In the flow proportional mode the sampler takes a sample in proportion to the
flow rate, independent of time. The lower the flow rate, the less frequent a
sample is taken and the higher the flow rate the more frequent a sample is
taken. The sampler can accumulate 1–9999 contact closures before a sample
is taken. Contact closures represent a discrete volume of wastewater
measured by a flow meter.
To initiate the flow proportional mode. place the EXT-MIN toggle switch to the
left, EXT.
Example: You wish to take one sample for every 5000 gallons of flow while
the flow meter sends one contact closure signal to the sampler for every 5
gallons of flow.
Therefore, the value entered in the Internal Between Samples thumbwheel
switch is 0100.
3.2.3 4–20 mA Proportional to Flow Operation
With a 4–20 mA input signal, the Interval Between Samples setting represents
the number of minutes between samples at the maximum flow rate. To
determine the number of output pulses between samples, figure the total
number of samples and collection time period over which they are to be
collected. Use the steps below to determine the “Total Count” value that is
entered when programming the sampler:
Table 7 Number of Sample Events Taken in a 48-hour Period
Selector Knob—Black Outer Band Set INTERVAL BETWEEN SAMPLES Thumbwheel Switch
24 0120
48 0060
96 0030
144 0020
192 0015
288 0010
Table 8 Number of Sample Events Taken in a 72-Hour Period
Selector Knob—Black Outer Band Set INTERVAL BETWEEN SAMPLES Thumbwheel Switch
24 0180
48 0090
72 0060
96 0045
144 0030
192 0022
288 0015
5000 gal
1 sample
------------------------
1 contact closure
50 gal
---------------------------------------------
×
100 contact closures per sample
=