ABB TTF300 Instrucciones Para La Puesta En Funcionamiento página 57

4.5.1.1 Standard application with HART functionality
Fig. 9
A Transmitter
Adding resistance R250 increases the minimum supply voltage:
U
Mmin
Where
U
Mmin
U
Smin
R : Line resistance between transmitter and power supply
Ltg
R : Resistance for HART functionality
250
CI/TTF300-X1
Field
A
≤ U
+ 0.02A x (R + R
Smin Ltg
: Minimum operating voltage of transmitter (refer to technical data for transmitter)
: Minimum supply voltage of power supply / SPS input
R
+
U
M
-
R
Ltg
B Power supply / SPS input with supply
)
250
TTF300
Electrical connections
Control room
250 +
U
S
-
B
A00095
EN - 21