Hach Ultra ORBISPHERE 3624, Руководство оператора

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3624 ProBrix Plus - Instrument Setup 39 of 96
Operator Manual
ORBISPHERE
3.2 Thermal Cutoff (instrument only)
If the sample temperature is liable to exceed the compensated temperature range of the
CO
2
or O
2
sensor, you can set an upper temperature limit to automatically cut off the
electrical signal to the sensor to extend the sensor's life.
Under the
MODIFY OPTIONS
menu, highlight
THERMAL CUTOFF
and press
ENTER
.
Choose the sensor (either
CO2
or
O2
).
The CO
2
sensor can be
ENABLED
or
DISABLED
. Select
ENABLED
to move to the data
entry screen, or
DISABLED
to disable this option for the CO
2
sensor.
Once enabled, if the sample temperature exceeds this limit, then alarms are set and a
warning message is sent to the PC. In addition, a
Warning Thermal Cutoff
message
flashes periodically on the instrument LCD.
3.3 Setting Instrument Alarm Limits
If the change product mode is set to
PC ONLY
(see “Change Product” on page 42 ),
alarm limits can only be set from the ProBrix Plus PC Program and cannot be changed
directly from the instrument.
It is recommended that you use the ProBrix Plus PC Program to set alarm limits, as the
limits set by the program are stored permanently. If you use the instrument, the values
set here will be overridden by the stored PC values the next time the product is selected.
The instrument provides two alarm relays (
High/Low
and
Low-Low/High-High
), which
can be set separately for CO
2
and Brix/Diet measurement limits. If any measurement is
outside of these limits, an alarm relay is activated as indicated in Table 3-4 .
* CO
2
, O
2
, or Brix/Diet measurement, as applicable
** On means the alarm relay is closed. Off means the relay is open. Your
Hach Ultra representative can electronically reverse the default open and
closed status.
Selecting the O
2
sensor will take you directly to the data
entry screen.
Enter the thermal cutoff value.
Table 3-4:
Alarm Relay Table
Alarm Condition High/Low
Relay**
High-High/Low-
Low Relay**
No
alarm: Low Limit < measurement* <High Limit off off
Low
alarm: Lo-Low Limit < measurement* < Low Limit on off
High
alarm: Hi-High Limit > measurement* > High Limit on off
Low-Low
alarm: measurement* < Lo-Low Limit on on
High-High
alarm: measurement* > Hi-High Limit on on
System
alarm: see
“Warning Messages” on page 30
on on