ATR 621 - User manual 11
Shield/Schermo
For thermoresistances PT100
•  For a three-wires connection use cables with 
the same diameter.
•  For a two-wires connection short-circuit termi-
nals 16 and 18.
•  When shielded cable is used, it should be 
grounded at one side only.
16
17
18
RED/ROSSO
WHITE/BIANCO
RED/ROSSO
Shield/Schermo
For linear signals Volt/mA
•  Comply with plarity 
•  When shielded cable is used, it should be 
grounded at one side only.
Examples of connection for linear input AI1
For linear signals 0….10V
  •  Comply with polarity
PRESSURE TRANSMITTER
For linear signals 0/4….20mA with three-wires 
sensors
  •  Comply with polarity
C = Sensor output
B = Sensor ground
A = Sensor supply (12Vdc/25mA)
PRESSURE TRANSMITTER
SENSORE DI PRESSIONE
EXTERNAL SUPPLY
ALIMENTAZIONE ESTERNA
For linear signals 0/4..20mA with external power 
supply for sensor
  •  Comply with polarity
C = Sensor output
B = Sensor ground