YOKOGAWA Rotamass series - Page 56

General Instruction Manual
Wiring
Transmitter
56 / 90
IM 01U10B00-00EN-R, 3rd edition, 2018-07-09
Passive current
output lout
Value
Nominal output current 4 – 20 mA
Maximum output current range 2.4 – 21.6 mA
External power supply 10.5–32 V
DC
Load resistance for secure HART communi-
cation
230–600 Ω
Load resistance at current output ≤ 911 Ω
Additive maximum deviation 8 µA
Additive output deviation for deviation from
20 °C ambient temperature
0.8 µA/ °C
R =
U - 10.5 V
0.0236 A
911
U in V
32
10.5
R in Ω
0
Fig.39: Maximum load resistance as a function of an external power supply voltage
R Load resistance
U External power supply voltage
The diagram shows the maximum load resistance R as a function of voltage U of the con-
nected voltage source. Higher load resistances are allowed with higher power supply val-
ues. The usable zone for passive power output operation is indicated by the hatched
area.
U
R
Iout+
Iout-
ROTAMASS
Fig.40: Passive current output connection lout