Honeywell STT25D, Руководство оператора

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Smart Temperature Transmitter STT250 – Operator Manual 9
NOTE: Even though the transmitter is working properly, the SFC may display
"CRITICAL STATUS" and an error message when you press "STATUS".
The error messages are "INPUT OPEN" "UNCERTAIN READING" "I/P OUT OF
SPEC".
The " CRITICAL STATUS " message is caused by one of the following:
⇒
You have not connected a sensor to the input.
⇒
There is an open circuit in the sensor, connecting wiring or terminal connections.
⇒
You have connected a T/C or other milli-volt source to the T/C terminals and the
transmitter is configured for RTD input (or vice versa).
3. Press " Status " to verify " Status Check = OK " is displayed.
4. Press " Conf " to access the transmitter database and configure it as required. As
mentioned earlier, the default shipping mode of engineering units is
0-45 mV input, mV range.
You can now customize the unit to your specific application. The flow chart in Figure 4
gives a simplified overview of selections and key strokes.
See SFC Operating Card 34-ST-11-16 for more details on Latching, NAMUR and
Write Protection functionalities.
In summary: - Press " Next " (or ) and " Prev " (or ) to scroll through the
different categories.
- Press "
Menu Item " to access the possible selections of any
category: the
è
key steps on to the next selection while the
ç
key steps back to the previous selection.
Note that with the " Menu Item " key you can only move to the right.
5. When a desired configuration item appears on the SFC display, this item may be
configured in the SFC
"Hold" memory by pressing " Enter ".
When you have completed configuring all items accessible via the " STT Conf "
Key, or you try to exit via the " CLR " Key, the SFC will ask " Download Change? ".
Press " Yes " (Enter) and the changes will be down-loaded from the SFC to the
transmitter, or press " No " (CLR) and the SFC hold memory will be erased.
6. Having now configured the input type etc., press " LRV " and key in the required
temperature for 4 mA output (e.g. 100
°
C [212
°
F]).
7. Press " Enter " to load this into the transmitter and repeat with " URV " for the 20 mA
output (e.g. 500
°
C [932
°
F]).
Note that if the input type is changed or the output type is changed from linear
to non-linear (or vice versa), the LRV and URV values will default to factory set
values and the unit selection (
°
C/
°
F) will default to
°
C.
Your STT250 is now configured for your applications.
You can check out the performance by varying the input and observing the output
response on the DVM.