User manual

Publication 1797-6.5.1 - April 1999
Applying FLEX Ex Analog I/O Modules 6-3
Important:As not all protection methods are applicable for all locations,
consult local certifying agencies to determine acceptable
protection methods for your application.
Match Field Devices
and I/O Modules
You must match field devices and I/O modules for your application to
function properly. Consider the following:
• Verify field device and I/O module operational characteristics
• Match entity parameters of field devices and I/O modules
P/I Analog Transmitter Functional and IS Parameters
The figure below shows a typical pressure to current analog transmitter.
Two types of characteristics are shown, functional and IS.
1797-IE8 Functional and IS Parameters
The figure below provides data, on the Flex Ex analog input module, which
can be matched to this transmitter.
600
250
10.5 16.4 24.7 42
4-20mA IS
P/I Transmitter
10.5-42V operate
EEx ia IIC T4
Ui=30V
Ii=165mA
Ci=22.5nF
Li=730uH
Power Supply Voltage
External
Load
Resistance
41662
I
Analog Input
V>17V at I=0mA
V>15.5 at I=20mA
V>15V at I=22mA
0-22mA Measurement Range
EEx ia/ib IIB/IIC T4
Uo<23.7V
Io<92.5mA
Flexbus
41662
IIB
Ca=560nF
La=10mH
IIC
Ca=66nF
La=2.5mH
P
+
-V
sig
–
+V
4-20mA
Xmit
91Ω
17V
22Ω
Bus
uC