COMMISSIONING
240 Service Manual Part No.: 4417340 Revision 1
954 SmartServo FlexLine
7.7.2.1 Wire temperature
The wire temperature compensation requires one configuration
parameter. This parameter is automatically set correctly when the
correct [Measuring range and wire type] is chosen (refer to section 7.4).
When <
No measuring range selected> or <Other measuring range or wire type> is
selected the wire temperature coefficient needs to be set manually:
Entity name Default Value Explanation
[Wire temperature coefficient] < 16x10
-6
[1/°C] >
Wire temperature coefficient. The default value is
for stainless steel 316.
7.7.2.2 Elongation free wire and Elongation wire on drum
These compensations require two configuration parameters. These
parameters are automatically set correctly when the correct
[Measuring range and wire type] is chosen (refer to section 7.4).
When <
No measuring range selected> or <Other measuring range or wire type> is
selected the elasticity coefficient (Young’s modulus) and the wire cross
sectional area need to be set manually:
Entity name Default Value Explanation
[Elasticity coefficient] < 200x10
9
[N/m
2
] >
Elasticity coefficient (Young’s modulus). The
default value is for stainless steel 316.
[Wire cross sectional area] < 3.1416x10
-9
[m
2
] >
Wire cross sectional area (0.25 * π * diameter
2
)
7.7.2.3 Tank shell
Thermal expansion of the tank shell or stilling well influences the
reference position of the 954 SmartServo FlexLine. A compensation
method shall be applied so that the total deviation for a temperature
change of 10°C falls within the maximum permissible error for the
installed SmartServo (according to OIML R85).
The compensation takes expansion of both the product and vapour
space area of the tank shell into account.
The SmartServo FlexLine must be equipped with the average
temperature option. Both the product and vapour temperature are
measured and used in the gauge reference compensation
calculations. The tank shell temperature is not a direct measured
parameter. It will therefore be calculated from product, vapour and
ambient temperatures. For ambient temperature several selections are
possible.