Hach SIGMA 900, Руководство пользователя

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Page 44
Programming the Sampler for Level Control
8837prg.fm
Section 5
predetermined level, a sample is taken within the first minute and the interval
automatically resets to the programmed time or flow interval.
Mode 3
When the liquid rises to a predetermined level, a sample is not taken
immediately. A sample is taken only when liquid is at or above the
predetermined level and after the programmed sample interval has elapsed.
The interval between samples counts down and resets even when the liquid
level is below the predetermined (actuation) level. This mode is used to
synchronize sample collection with a real-time clock when sampling in the
time mode.
5.11 Programming the Sampler for Level Control
Put the sampler in a standby state (i.e.
PROGRAM HALTED
,
READY TO START
or
PROGRAM COMPLETE
) hold the
CLEAR ENTRY
key for two seconds. This
will cause the display to read
LEVEL CONTROL?
. The following messages
may be displayed in the level control program:
5.12 Storm Water Programming
EPA regulations for storm water discharges require monitoring of
precipitation, flow and water samples in order to assess the impact of storm or
snow melt runoff on receiving waters. The manufacturer can help to create a
storm water monitoring system that consists of a multiple bottle sampler, an
external flow meter, and a tipping bucket rain gauge.
In addition to performing basic sampling routines, Sigma 900 All Weather
Refrigerated Samplers that are equipped with the storm water monitoring
program have the following additional capabilities.
• The storm water sampling routine allows collection of automatic grab
sample(s) at user-selectable timed intervals (up to 24 different intervals
may be selected) during the storm's early stage or “first flush”. First flush
grab and main program flow weighted composite samples are
automatically segregated. The first flush sample volume may be set
independently of the sample volume for the flow weighted composite.
• The special storm water program allows an external device to initiate the
start of the sampling program. A dry contact closure across Pins B and D
on the Auxiliary receptacle, held closed for at least 61 seconds, is
required.
Item
Number
Message Description of Message
1 LEVEL CONTROL
If you press
NO
,
SPECIAL OUTPUT?
will appear on the display. The Special Output
feature is explained on page 46 . If you press
YES
, the display shows item 2.
2 STORM MODE?
If you press
YES
, the sampler functions in Storm mode. Storm mode programming is
described in section 5.12 . If you press
NO
, the display shows item 3.
3 LEVEL START?
If you press
YES
, the sampler operates as described in Mode 1. If you press
NO
, the
display shows item number 4.
4 LEVEL START/STOP
If you press
YES,
the sampler operates as described in Mode 2. If you press
NO
, the
display shows item number 5.
5 SAMPLE ON LEVEL?
If you press
YES,
the sampler operates as described in Mode 3. If you press
NO
, the
display shows item number 1.