13 
10.7 Serial communication 
Models ATR121-xT , ATR141-xT 
 
 
 
 
RS485, protocol MODBUS-RTU  
 Do not use LT  (line termination) 
resistors 
 
 
11 - ALARM INTERVENTION MODES 
 
11.1 Absolute Alarm or Threshold Alarm  (  
selection) 
 
 
On On
Off Off
Pv
> 0
Hysteresis
parameter
Time
Alarm
output