Setting The Measurement Bias; Table 15: Device Menu - ABB 266 MODBUS User Manual

Setting the measurement bias

Removing offsets
An important part of device installation is removing the offsets that may occur during shipment, handling, positioning, or other
sources.
Examples of installation issues that could cause a zero shift include: a slightly inclined mounting position, different liquid
columns in the differential pressure lines, and remote seals.
IMPORTANT NOTE: For accurate correction, the transmitter must be allowed to acclimate to the surrounding
temperature and achieve operating temperature (Operating temperature is achieved approximately 5 min after
power is applied). The acclimation process may also be completed within the warm up period.
Standard acclimation time: 1 minute for each 1 °C difference at start-up
For example:
Acclimation time (15 minutes)
Optimum warm-up time (20 minutes) = Operating temperature (5 minutes)
The correction must also be made at zero flow (DP = 0).
To remove the offsets, use the bias options in the Device Setup menu (Table 15).
Menu
Device Setup
Device Setup, Cont.
= Application sight temperature (30° C)

Table 15: Device menu

Submenu 1 Submenu 2
Set Diff. Press Units
Lower Range Value
Upper Range Value
Damping
Set Diff. Press Bias
Set DP To Zero
Set DP To value
Reset DP Bias
Set Static Press. Units
Lower Range Value
Upper Range Value
Set Static Press., Cont. Damping
Set Static Press. Bias
Set SP To Value
less transmitter temperature (15° C).
plus acclimation time (15 minutes)
Selections or Description
Pa
Mpa
bar
PSI
kPa
mbar
Applies a bias to make the current displayed
value equal zero
Applies a bias to make current displayed value
equal the entered value
This removes the user saved bias
Pa
Mpa
bar
PSI
kPa
mbar
Applies a bias to make current displayed value
equal the entered value
266 MODBUS® multivariable transmitter User manual 2105216 Rev. AB | 65
5 Service and maintenance
inH2068F kg/cm2
inH2060F mmH2068F
inH204C ftH2068F
Torr inHgOC
Atm mmHgOC
g/cm2
inH2068F kg/cm2
inH2060F mmH2068F
inH204C ftH2068F
Torr inHgOC
Atm mmHgOC
g/cm2