- 18 -
. . . ADDENDUM FOR "METERS" OPTION OF THE TRANSMITTERS
The calibration can be performed in output current or percentage,
or in process engineering units (see fig. 2).
Proceed as follows:
A) OUTPUT CURRENT (4
÷
20 mA)
1) The switches from SW1 to SW6 must be positioned as
follows :
ON - OFF - ON - OFF - ON - OFF
2) Set the output current of the current generator to 4 mA,
reading it on the milliammeter or 1 V. on the DVM.
Alternatively force, using the "Loop Test" procedure on
the Hand Held Communicator, the output of your Smart
transmitter to 4 mA.
3) Adjust the zero trimmer (Z) to read approximately 4.00
4) Set the output current to 19.9 mA, reading it on the
milliammeter, or 4.975 V. on the DVM. Alternatively
force the output of your Smart transmitter to 19.9 mA
checking for this value in the Hand Held Communicator.
5) Adjust the span trimmer (S) to read approximately 19.90.
6) Repeat the points 2) 3) to read exactly 4.00 (
±
0.1)
7) Repeat the points 4) 5) to read exactly 19.90 (
±
0.1).
8) Fit the "mA" unit label in the right recess below the
indication.
B) OUTPUT PERCENTAGE (0
÷
100%)
1) The switches from SW1 to SW6 must be positioned as
follows :
ON - OFF - ON - ON - OFF - ON
2) Set the output current of the current generator to 4 mA,
reading it on the milliammeter or 1 V. on the DVM.
Alternatively force, using the "Loop Test" procedure on
the Hand Held Communicator, the output of your Smart
transmitter to 4 mA.
3) Adjust the zero trimmer (Z) to read approximately 00.0
4) Set the output current to 20 mA, reading it on the
milliammeter, or 5 V. on the DVM. Alternatively force the
output of your Smart transmitter to 20 mA checking for
this value in the Hand Held Communicator.
5) Adjust the span trimmer (S) to read approximately 100.0.
6) Repeat the points 2) 3) to read exactly 00.0 (
±
0.1)
7) Repeat the points 4) 5) to read exactly 100.0 (
±
0.1)
8) Fit the "%" unit label in the right recess below the
indication.
C) ENGINEERING UNITS
The switches must be positioned as follows:
-1999
÷
-1000
-1000
÷
0
0
÷
1000
1000
÷
1999
OFF
ON
OFF
ON
OFF
OFF
ON
ON
SW1 SW2
For ZERO adjustment, between
100
÷
1000
1000
÷
2000
2000
÷
3000
3000
÷
3998
ON
OFF
ON
OFF
ON
ON
OFF
OFF
SW3 SW4
4.00
÷
19.99
40.0
÷
199.9
400
÷
1999
OFF
ON
OFF
ON
OFF
OFF
SW5 SW6
For SPAN adjustment, between
For DECIMAL POINT position, like
Then proceed as follows:
1) Set the output current of the current generator to 4 mA on
the milliammeter or 1 V. on the DVM. Alternatively, using
the "Loop Test" procedure on the Hand Held
Communicator, force the output of your Smart transmitter
to 4 mA.
2) Adjust the zero trimmer (Z) to read approximately the
lower range value (LRV) on the digital meter.
3) Set the output current to 20 mA, on the milliammeter or
5 V. on the DVM. Alternatively force the output of the
transmitter to 20 mA using the Hand Held Communicator.
4) Adjust the span trimmer (S) to read approximately the
upper range value (URV) on the digital meter.
5) Repeat the points 1) 2) to read exactly the LRV (
±
0.1).
6) Repeat the points 3) 4) to read exactly the URV (
±
0.1).
7) Complete the calibration procedure by fitting the
multiplication factor label (if any) in the left recess below
the display and the engineering unit label in the right
recess (see fig. 2).
INTEGRAL DIGITAL DISPLAY MICROPROCESSOR
DRIVEN (fig. 3)
This type of display is fitted in the Secondary Unit housing,
connected directly to the electronics and secured by a "Snap-
locking". Its primary use is the display of the transmitter's
output. The variables displayed are software programmable
and can be selected using the Hand Held Communicator or a
suitable P.C. based program:
- Process Variable
The PV value represents the primary variable (pressure) after
sensor trimming adjustment, or it may represent the "true
primary variable" applied (process variable) in its engineering
units, when the "PV scaling" function is active. (see the
Addendum for PV-Scaling operation)
- Percent of Range
- Process Va Percent of Range
- Process Va Output Current
When two variables are displayed they are shown alternating
every two seconds. A Process Value outside the display limits
(4 digits) will be shown as "9999" while a saturated output (>20
mA) will be shown as "E---". When square root or other output
conditioning is activated the appropriate symbol is displayed.
Fig. 3 - Microprocessor driven display
What has been described is for a HART version. The "Analog
only" transmitter can also have an integral digital display. It can
be configured from the factory to display the percent of range
and the output current in mA.
