Absolute Pressure Transmitter Re-Zeroing; Hardware Settings - ABB 2600T-Serie Bedienungsanleitung

4.5.2 Absolute pressure transmitter re-zeroing

Absolute pressure transmitter rezeroing is only possible when a
vacuum pressure generator is available. It is strongly
recommended to refer to the integral manual before
proceeding.
4.5.3 Non-zero based calibrated devices
(eg 4 .. 20 mA = - 100 .. 100 mbar)
1. Insulate the transmitter from the process and vent the
transmitter measuring chamber/s to atmosphere.
2. Apply the lower range value pressure (4 mA) from the
process or from a pressure generator. The pressure must
be stable and applied with a high level of accuracy
< 0.05 % (observing the set damping value).
3. Check the output signal of the transmitter, if it is at 4 mA
(or PV= 0) you do not need to re-zero the transmitter; if
the output is not at zero follow the below procedure:
Unscrew the data plate fixing screw on the top of
transmitter housing.
Rotate the data plate to get access to the push
buttons.
Be sure that the write protection rotating switch is set
to write enable.
Push the zero (Z) button on top of the transmitter for
at least 3 seconds.
The output will go to 4 mA, and if the Integral Display
is present, the message "OPER DONE" will appear. If
nothing happens check the write protection rotating
switch, it is probably set to write disable. In case of
other diagnostic messages, please refer to the
instruction.
4. Once the "Zero" operation has been accomplished the
transmitter needs to be reconnected to the process.
5. Close the vent / drain valves that may have been opened
6. Open the insulation valve/s (in case of differential pressure
transmitters please follow the following sequence:
open high pressure side insulation valve,
open low pressure insulation valve,
close equalizing valve.
Important. It is not necessary to remove the cover for this
procedure (Dip switch are already factory set)
Figure 7: External pushbuttons

4.6 Hardware settings

4.6.1 HART
There are 6 dip switches located on this kind of secondary
electronics (as indicated by the figure); they are used for
settings when integral display is not available.
Switch 1 and 2 allow the REPLACE MODE for sensor or
secondary electronics.
Switch 3 identifies the external push buttons functionalities:
Zero/Span adjustments or PV Bias-Offset / PV Bias Reset.
Switch 4 and 5 are for Fail Low/Fail High selection.
Switch 6: not used.
The electronic label clearly explains how to perform all the
possible selection, but please remember that all the operations
with the dip switches should be carried out when the
transmitter is powered off so as to upload new configurations
at instrument start-up.
Replace mode (switch 1 and 2)
Usually switches 1 and 2 are down in "0" position.
They are moved when a replace operation is required.
Switch 1 up in "1" position is required before power up the
transmitter, when user needs to replace the electronics or the
sensor.
Switch 2 down in "0" position allows the replace of the
secondary electronics. It must be moved in this position before
power up the transmitter.
Switch 2 up in "1" position indicates that a new sensor has
been installed.
AFTER ANY REPLACE OPERATION IT IS RECOMMENDED TO
MOVE DOWN IN "0" POSITION THE RELEVANT SWITCHES.
Push buttons mode (switch 3)
Dip switch 3 is set at the factory on "0" position. This means
that the external push buttons perform the zero/span
adjustments. If the user puts this switch on "1" position, the
zero push buttons will modify the PV Bias-Offset and the span
push button will reset the PV Bias-Offset value.
Fail mode (switch 4 and 5)
Should the user modify the factory-defined parameters for the
fail safe output condition in case of transmitter failure, it is
necessary to enable the modification by putting dip switch 4 on
"1" position. Consequently, it is necessary to choose whether
the output has to go Upscale or Downscale. Dip switch 5:
on "0" position the output is High (22mA)
on "1" position the output is Low (3,7mA)
2600T Series Pressure transmitters | SOI/266-XC Rev. D 11
4 Transmitter configuration