User Manual
Technical data   
A.12 Technical data: LOGO! AM2 RTD 
  LOGO! 
340  Manual, 04/2011, A5E03556174-01 
A.12  Technical data: LOGO! AM2 RTD 
  LOGO! AM2 RTD 
Power supply 
Input voltage  12/24 V DC 
Permissible range  10.8 ... 28.8 V DC 
Power consumption  30 ... 40 mA 
Voltage failure buffering  typ. 5 ms 
Power loss at 
•  12 V 
•  24 V 
•  0.36 ... 0.48 W 
•  0.72 ... 0.96 W 
Electrical isolation  No 
Reverse polarity protection  Yes 
Ground terminal  for connecting ground and shielding of the measuring 
line 
Sensor inputs 
Number  2 
Type  PT100 or PT1000 with the default temperature 
coefficient of α = 0.003850 for both types, or 
compatible sensors 
Connection of sensors 
•  2-wire technique 
•  3-wire technique 
•  Yes 
•  Yes 
Measurement range  -50 °C... +200 °C 
-58 °F ... +392 °F 
Settings for the measurement display on 
the LOGO! Basic: 
•  1 °C steps 
•  0.25 °C steps 
(rounded to one decimal) 
•  1 °F steps 
•  0.25 °F steps 
(rounded to one decimal) 
•  Offset: -50, Gain: 0.25 
•  Offset: -500, Gain: 2.50 
•  Offset: -58, Gain: 0.45 
•  Offset: -580, Gain: 4.50 
Curve linearization  No 
Measuring current Ic  Pulse current signal: 
PT100: 1.141 mA (cycle time = 2.3 ms) 
PT1000: 0.5 mA (cycle time = 2.3 ms) 
Measurement rate  depends on the installation 
typical: 50 ms 
Resolution  0.25 °C 
Error limits 
•  0 °C ... +200 °C 
•  -50 °C ... 0 °C 
of the final measured value: 
•  ± 2 °C 
•  ± 3 °C 
Electrical isolation  No 










