VEGA WEIGHTRAC 31 4 … 20 mA_HART - four-wire User Manual
Page 67
67
10 Supplement
WEIGHTRAC 31 • 4 … 20 mA/HART - four-wire
42374-EN-131119
Transistor output
Output
Floating transistor output, permanently shortcircuit-proof
Load current
< 400 mA
Voltage loss
< 1 V
Switching voltage
< 55 V DC
Blocking current
< 10 µA
Accuracy (according to DIN EN 60770-1)
Process reference conditions according to DIN EN 61298-1
Ʋ Temperature
+18 … +30 °C (+64 … +86 °F)
Ʋ Relative humidity
45 … 75 %
Ʋ Air pressure
860 … 1060 mbar/86 … 106 kPa (12.5 … 15.4 psig)
Repeatability
1 % of the measuring range end value
Deviation with bulk solids
The values depend on the quality of the linearization
Deviation under EMC influence
≤ 1 %
Variables influencing measurement accuracy
Specifications apply also to the current output
Temperature drift - Current output
±0.03 %/10 K relating to the 16 mA span max. ±0.3 %
Deviation on the current output through
analogue/digital conversion
<±15 µA
Deviation on the current output due to
strong, high frequency electromagnetic
interference acc. to EN 61326
<±150 µA
Characteristics and performance data
Step response time
4)
≤ 5 s (with damping 1 s)
Ambient conditions
Ambient, storage and transport tempera-
ture
-40 … +60 °C (-40 … +140 °F)
Process conditions
For the process conditions, please also note the specifications on the type label. The lower value
always applies.
Process pressure
Unpressurized
Process temperature (measured on the
detector tube)
-40 … +60 °C (-40 … +140 °F)
Vibration resistance - sensor
5)
mechanical vibrations up to 1 g in the frequency range
5 … 200 Hz
Vibration resistance - mounted in the
measuring frame
mechanical vibrations up to 1 g in the frequency range
5 … 200 Hz
4)
Time span after a sudden measuring distance change by max. 0.5 m in liquid applications, max 2 m with bulk
solids applications, until the output signal has taken for the first time 90 % of the final value (IEC 61298-2).
5)
Tested according to the guidelines of German Lloyd, GL directive 2.