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Reference Manual
00809-0100-4021, Rev DA
November 2004
4-17
Rosemount 3144P
FOUNDATION Fieldbus
AI2 as Terminal Temperature (body temperature)
1. Put the AI Block into OOS mode.
a. Go to MODE_BLK.TARGET
b. Choose OOS (0x80)
2. Go to CHANNEL
a. Choose Body Temperature
3. Go to L_TYPE
a. Choose Direct
4. Go to XD_Scale
a. Choose UNITS_INDEX to be °F
b. Set 0% = –40, set 100% = 185
5. Go to OUT_SCALE
a. Choose UNITS_INDEX to be °F
b. Set the 0 and 100 scale to be the same as in step 4b.
6. Put the AI Block back into Auto mode.
7. Follow Host Procedure to download schedule into Block.
Filtering NOTE
If damping has already been configured in the Transducer Block, setting a
non-zero value for PV_FTIME will add to that damping.
The filtering feature changes the response time of the device to smooth
variations in output readings caused by rapid changes in input. Adjust the
filter time constant (in seconds) using the PV_FTIME parameter. Set the filter
time constant to zero to disable the filter feature.
Process Alarms Process Alarm detection is based on the OUT value. Configure the alarm
limits of the following standard alarms:
• High (HIGH_LIM)
• High high (HIGH_HIGH_LIM)
• Low (LOW_LIM)
• Low low (LOW_LOW_LIM)
In order to avoid alarm chattering when the variable is oscillating around the
alarm limit, an alarm hysteresis in percent of the PV span can be set using the
ALARM_HYS parameter. The priority of each alarm is set in the following
parameters:
•HIGH_PRI
• HIGH_HIGH_PRI
•LOW_PRI
• LOW_LOW_PRI