Reference Manual
00809-0100-4021, Rev FB
August 2011
Rosemount 3144P
3-20
HART
Figure 3-6. Change in Input
versus Change in Output with
Damping Enabled.
Alarm and Saturation
Field Communicator
The
Alarm/Saturation
command allows the user to view the alarm settings
(Hi or Low). This command can change the alarm and saturation values.
To change the alarm and saturation values, select the value to be
changed, either
1 Low Alarm
,
2 High Alarm
,
3 Low Sat.
,
4 High Sat,
or
5
Preset Alarms
and enter the desired new value which must fall within the
guidelines below:
• The low alarm value must be between 3.50 and 3.75 mA
• The high alarm value must be between 21.0 and 23.0 mA
The low saturation level must be between the low alarm value plus 0.1 mA
and 3.9 mA for the standard HART transmitter. For the safety certified
transmitter, the lowest saturation setting is 3.7 mA and the highest is 20.9
mA.
Example: The low alarm value has been set to 3.7 mA. Therefore, the low
saturation level, S, must be as follows:
3.8
S
3.9 mA.
The high saturation level must be between 20.5 mA and the high alarm
value minus 0.1 mA for the HART transmitter. The highest saturation
setting for the transmitter is 20.9 mA.
Example: The high alarm value has been set to 20.8 mA. Therefore, the
low saturation level, S, must be as follows:
20.5
S
20.7 mA.
Preset alarms can either be
1 Rosemount
or
2 NAMUR-compliant
. Use the
failure mode switch on the front side of the electronics (see “Switch
Location” on page A-11) to set whether the output will be driven to high or
low alarm in the case of failure.
100.0
101.0
102.0
103.0
104.0
105.0
106.0
107.0
108.0
109.0
110.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5 10.0
Input Value
Output Value
Time (Seconds)
T
em
p
erat
ure
Traditional Fast Keys
1, 3, 4, 2
Device Dashboard
Fast Keys
2, 2, 5, 6
Aotewell Ltd
www.aotewell.com
Industry Automation
HongKong|UK|China
+86-755-8660-6182
