9.3.10
Connecting Resistance
Thermometers in the
Standard Pt 100 Range
The series-connected resistance thermometers (up to 8 Pt 100s) are fed
with a current of 2.5 mA (I
C+
/I
C-
) by a constant current generator. The
voltage at the Pt 100’s is picked off at measurement inputs M+ and M-.
In this mode, the whole temperature range of the Pt 100 (-200 °C to
+840 °C) is available. The mode is printed on the cover of the module
as follows:
"resistance thermometer uncompensated full range".
Other voltage sensors can be connected in a floating circuit at the
M+/M- inputs of a card which are not assigned to resistance
thermometers (voltage range 500 mV).
1)
If no Pt 100 is connected to CH4 to CH7, other voltages and currents can be measured at these channels with cards
6ES5 498-1AA21, 6ES5 498-1AA31, 6ES5 498-1AA41, 6ES5 498-1AA51, 6ES5 498-1AA61, 6ES5 498-1AA71.
2)
When cards 6ES5 498-1AA41, 6ES5 498-1AA51 or 6ES5 498-1AA71 are used, a short-circuit jumper is not required.
0 ... 500 mV
L +
460 Analog Input Module
L -
+
MUX
A
D
-
Card 1
Card 2
1)
U
CM
U
CM
0 V Bus
Pt 100
Pt 100
Pt 100
Pt 100
0 ... 500 mV
2)
2.5 mA
I
const.
IC +
I
C -
CH0
CH1
CH2
CH3
CH4
CH7
M +
M -
Range
Card for
4 Inputs
6ES5 498-
-1AA11
Range
Card for
4 Inputs
6ES5 498-
-1AA11
#
Figure 9-9
Connecting Resistance Thermometers in the Standard Pt 100 Range
The 460 Analog Input Module
System Manual
9 - 22
C79000-B8576-C109-03
