Tecfluid MX4B - Manual (Page 19)

19
3.1 Current loop connection
Terminal
12 mA (+)
13 mA (-)
The mA output is galvanically isolated.
NOTE: The analog output incorporates a protection against polarity inversion. Due to a
second overvoltage protection, if a power supply voltage higher than 32 V is connected,
the converter could be damaged.
In the case of a HART transmitter, an external resistor (R) must be included. Its minimum
value will be 200 Ω, and the maximum value will depend on the current loop power
supply.
Therefore, the minimum operating voltage will be V = 16 V.
This value is calculated without taking into account the resistance of the cable.
This resistance will depend on each cable type and length, and must be added to the load
resistor to calculate the minimum operating voltage of the system.