VEGA MINITRAC 31 4 … 20 mA_HART - four-wire - Manual (Page 77)

77
11 Supplement
MINITRAC 31 • 4 … 20 mA/HART - four-wire
40447-EN-131119
Relay output
Output
Relay output (SPDT), floating spdt
Switching voltage
Ʋ Min. 10 mV
Ʋ Max. 253 V AC, 253 V DC
Switching current
Ʋ Min. 10 µA
Ʋ Max. 3 A AC, 1 A DC
Breaking capacity
Ʋ Min. 50 mW
Ʋ Max. 750 VA AC, 40 W DC
If inductive loads or stronger currents are switched
through, the gold plating on the relay contact surface will
be permanently damaged. The contact is then no longer
suitable for switching low-level signal circuits.
Contact material (relay contacts) AgNi or AgSnO and Au plated
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 ≤ 0.1 %
Deviation with bulk solids The values depend to a great extent on the application.
Binding specifications are thus not possible.
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