Specifications

Publication 1794-SG002D-EN-P - May 2012
Select FLEX Ex I/O Modules 93
Schematic Drawing of the 1797-IE8 Module
FLEX Ex Analog Input Comparison
Specification 1797-IE8 1797-IE8NF 1797-IE8H
Input resolution 16 bits
Input signal range 0…22 mA
Transfer characteristics, temperature
drift
0.1% of output signal range at 20 °C (68 °F)
Functional data range > 15V @ 22 mA
> 21.5V @ 0 mA
> 17V @ 22 mA
> 23V @ 0 mA
Data format Configurable
Step response to 99% of Full Scale 4 ms 80 ms 100 ms
Update time, module to adapter 200…1600 μs
Noxious gas exposure Tested to severity level G3, ISA-S71.04-1985
FLEX Ex power consumption 7.5 W @ 9V 7.1 W @ 9V
Power dissipation, max 5.2 W
Thermal dissipation, max 17.75 BTU/hr 13.5 BTU/hr
Instrinsically safe input type U
o
≤ 23.7V
I
o
≤ 93.5 mA
P
o
≤ 555 mW
U
o
≤ 24.4V
I
o
≤ 92.5 mA
P
o
≤ 565 mW
II (1)2G Ex ib[ia] IIC T4
Class I,
Div. 1, Groups A-D and Class I, Zone 1,
AEx ib [ia] IIC
Dimensions (HxWxD), approx. 46.0 x 94.0 x 75.0 mm
(1.8 x 3.7 x 2.95 in.)
Power supply
+V
-V
4…20 mA
Xmit
Bus
μC
FlexBus
Isolated
power
Valve
+
sig
4…20 mA
Xmit
21V
286 Ω
22 Ω
-