Hach SIGMA 900, User Manual

Page: 47 / 94

Section 5
Page 47
8837prg.fm
Special Outputs
The valve isolates the sampler intake tubing from the pressurized line
between samples and facilitates changing the pump tube. It is necessary to
have an external separate power supply/source to operate the valve.
Mode 3 (Fault Output)
The sampler sends a 12 V dc output for one second in the event of a missed
sample.
Mode 4 (Trouble Output)
A 12 V dc output occurs for one second if the sampler detects any of the
following conditions: low main battery, low memory battery (internal lithium
battery needs to be replaced), purge failure (the pump failed to purge the
intake tubing), and jammed distributor arm (arm not over a bottle).
Note about Wiring for Special Outputs
When wiring the special outputs signal to a relay for signal generating, wire a
protection diode in parallel with the coil. The diode will keep the voltage spike
created by the de-energized collapsing relay coil from feeding back into the
sampler special outputs circuitry and damaging the sampler. This diode can
be an IN4004 or equivalent.
5.13.1 Programming the Sampler for Special Outputs
With 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?
.
5.13.2 Other Displayed Messages for Special Outputs
Item
Number
Message Description of Message
1 LEVEL CONTROL? If you press the
NO
key, item 2 will appear on the display.
2 SPECIAL OUTPUT? If you press the
YES
key, item 3 will appear on the display.
3 SAMPLE OUTPUT
If you press the
YES
key, the sampler to operate as described in Mode 1. If you press
the
NO
key, the display continues with Event Output.
4 EVENT OUTPUT
If you press the
YES
key, the sampler operates as described in Mode 2. If you press the
NO
key, the display continues with Fault Output.
5 FAULT OUTPUT
If you press the
YES
key, the sampler operates as described in Mode 3. If you press the
NO
key, the display continues with Trouble Output.
6 TROUBLE OUTPUT
If you press the
YES
key, the sampler operates as described in Mode 4. If you press the
NO
key, the display will return to the previous mode.
Message Description of Message
YES/NO or * TO
BACKUP
This message appears if a key other than
YES
or
NO
is pressed and the displayed message is
followed by a question mark while in the Parameter Entry, Programming Running, or Time Set
modes.
WHILE RUNNING, KEY
0 - 1 - 2 ONLY
This message appears if a key other than
0
,
1
, or
2
is pressed while the program is running. The
program must be halted (press the
2
key) before any manual operations are performed, such as
Bottle Advance, Pump, Purge, Take Sample, New Program, etc.
REVIEW RESULTS?
This message appears if
DISPLAY FEEDBACK
is pressed and the sample program has been halted.
A
YES
response will cause the sample program results to appear. A
NO
response causes
REVIEW
PROGRAM?
to appear.