75
11 Supplement
VEGAPULS 68 • Foundation Fieldbus
36538-EN-170405
Ʋ ø 95 mm (3.74 in)
up to 50 m (164 ft)
Ʋ Parabolic antenna
up to 75 m (246.1 ft)
Output variable
Output
Ʋ Signal
digital output signal, Foundation Fieldbus protocol
Ʋ Physical layer
according to IEC 61158-2
Damping (63 % of the input variable)
0 … 999 s, adjustable
Channel Numbers
Ʋ Channel 1
Process value
Ʋ Channel 8
Electronics temperature
Transmission rate
31.25 Kbit/s
Current value
Ʋ Non-Ex and Ex ia instrument
12 mA, ±0.5 mA
Ʋ Ex-d-ia instruments
16 mA, ±0.5 mA
Resolution, digital
> 1 mm (0.039 in)
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)
Installation reference conditions
Ʋ Min. distance to internal installations > 200 mm (7.874 in)
Ʋ Reflector
Flat plate reflector
Ʋ False reflections
Biggest false signal, 20 dB smaller than the useful signal
Deviation with liquids
See following diagrams
1,0 m (3.28 ft)
10 mm (0.394 in)
2 mm (0.079 in)
- 2 mm (- 0.079 in)
- 10 mm (- 0.394 in)
0
1 2
3
Fig. 56: Deviation under reference conditions
1 Reference plane
2 Antenna edge
3 Recommended measuring range
Repeatability
≤ ±1 mm