ABB 265GS - Accuracy and Influences

Specifications
74 265Gx, 265Ax IM/265Gx/Ax-EN-07
9.6 Measuring accuracy
Change from one to two colu mns
Reference conditions according to IEC 60770
• Ambient temperature T
U = constant, in range: 18 ... 30 °C
(64 ... 86 °F)
• Relative humidity = constant, in range: 30 ... 80 %
• Atmospheric pressure P
U = constant, in range: 950 ... 1,060 mbar
• Position of measuring cell: vertical ±1 °
• Span based on zero position
• Isolating diaphragm material: Ceramic (Al
2
O
3
), gold-coated, or
Hastelloy C276
TM
• Sensor filling liquid: Silicone oil (sensors >
2.5 bar)
• Supply voltage: 24 V DC
• Load with HART: 250 Ω
• Transmitter not grounded
• Characteristic setting: linear, 4 ... 20 mA
Unless otherwise specified, errors are given as a percentage of the
span value.
The accuracy of the measurement in relation to the upper range limit
(URL) is affected by the turndown (TD); i.e., the ratio of the upper
range limit (URL) to the set span (URL/span).
IMPORTANT (NOTE)
Select the transmitter sensor with the smallest possible
turndown. This optimizes the accuracy of the measurement.
Dynamic response (according to IEC 61298-1)
Devices with standard configurations and a turndown of up to 30:1,
plus linear output characteristics.
Reaction time: 30 ms
Time constant (63 %) 150 ms (for all sensors)
Measuring error (for setting cut-off point)
Percentage of set span, consisting of non-linearity, hysteresis, and
non-reproducibility.
In the case of fieldbus devices, SPAN refers to the analog input
function block output scale range.
Turndown Measuring error
1:1 to 10:1 ±0.04 %
>10:1 ± (0.04 + 0.005 x TD - 0.05) %
Change from one to two colu mns
9.7 Operating influences
Change from one to two colu mns
Thermal change in ambient temperature
as regards zero signal and span (turndown up to 15:1),
in relation to the set span
Area Maximum effect on zero signal and span
-10 … 60 °C
(14 … 140 °F)
Sensor code C, F:
± (0.08 % x TD + 0.08 %)
Sensor code C, F (abs.)
± (0.20 % x TD + 0.10 %)
Sensor code L, D, U, R, V:
± (0.06 % x TD + 0.06 %)
-40 … -10 °C
(-40 … 14 °F) and
60 ... 80 °C
(140 ... 176 °F)
Sensor code C, F:
± (0.04 % / 10 K x TD + 0.05 % / 10 K)
Sensor code C, F (abs.):
± (0.10 % / 10 K x TD + 0.05 % / 10 K)
Sensor code L, D, U, R, V:
±(0.04 % / 10 K x TD + 0.04 % / 10 K)
Power supply
Within the specified limits for the voltage / load, the total influence is
less than 0.001 % of the upper measuring range limit per volt.
Load
Within the specified load / voltage limits, the total influence is
negligible.
Electromagnetic fields
Total effect: less than 0.05 % of span from 80 … 1,000 MHz and for
field strengths up to 10 V/m when tested with unshielded conduit, with
or without meter.
Mounting position
Nominal position: vertical; process connection at bottom.
The filling fluid of the measuring equipment affects the position if the
mounting position differs. If the deviation is 90° from the nominal
position and silicone oil is used as the filling fluid, this equates to
2.14 mbar + 0.02 mbar/10K.
Long-term stability
±(0.05 x TD) % / year
±(0.15 x TD) % / 5 years
Vibration effect
±(0.10 x TD) % acc. to IEC 61298-3.
Total performance
Similar to DIN 16086
In the range -10 … 60 °C (14 … 140 °F), in relation to the set span
(TD 1:1):
Sensor code C, F: ± 0.16 %
Sensor code C, F (abs.): ± 0.30 %
Sensor code L, D, U, R, V: ± 0.13 %
The total performance accuracy includes the measuring error (non-
linearity including hysteresis and non-reproducibility), as well as the
thermal change in the ambient temperature as regards the zero signal
and span.

22
21 lin
EEE
perf
E 




fper
E = Total performance
1
E
= Effect of the ambient temperature on the zero signal
2E = Effect of the ambient temperature on the span
lin
E
= Measurement deviation (for setting cut-off point)
Change from one to two colu mns