Emerson 4500 Manuel D’Utilisation

Page de 70
Reference Manual 
00809-0100-4027, Rev AA
December 2005
3-9
Rosemount 4500
Rerange with a HART Communicator Only
The easiest way to rerange is to use the HART Communicator only. This 
method changes the values of the analog 4 and 20 mA points independently 
without a pressure input.
From the HOME screen, enter the fast key sequence for “Rerange with a 
Communicator Only.” 
1. At “Keypad Input” select 1 and use the keypad to enter lower range 
value. 
2. From “Keypad Input” select 2 and use the key pad to enter upper range 
value. 
Rerange with a Pressure Input Source and HART Communicator
Reranging using the HART Communicator and a pressure source or process 
pressure allows reranging the transmitter when specific 4 and 20 mA points 
are unknown. 
NOTE
The span is maintained when the 4 mA point is set. The span changes when 
the 20 mA point is set. If the lower range point is set to a value that causes the 
upper range point to exceed the sensor limit, the upper range point is 
automatically set to the sensor limit, and the span is adjusted accordingly.
1. From the HOME screen, enter the fast key sequence for “Rerange with a 
Pressure Input Source and a HART Communicator” to configure lower 
and upper range values and follow the on-line instructions.
Rerange with a Pressure Input Source and the 
Local Zero and Span buttons (option D1)
The transmitter may be reranged using the local zero and span adjustments 
and a pressure source.
1. Using a pressure source with an accuracy three to ten times the desired 
calibrated accuracy, apply a pressure equivalent to the lower range value 
to the transmitter.
2. Push and hold the zero adjustment button for at least two seconds but no 
longer than ten seconds.
3. Apply a pressure equivalent to the upper range value to the transmitter.
4. Push and hold the span adjustment button for at least two seconds but 
no longer than ten seconds.
Fast Keys
1, 2, 3, 1, 1
Fast Keys
1, 2, 3, 1, 2
ALARM
SPAN
-LOOP
+LOOP
ZERO
SECURITY
Span
Zero