Input filter cutoff -3, Input filter cutoff – Rockwell Automation 1797-IRT8 FLEX Ex Thermocouple/RTD/mV Input Module User Manual User Manual
Page 17
Publication 1797-6.5.2 - February 2001
Understanding Configurable FLEX Ex Thermocouple/RTD/mV Input Module Features 2-3
Input Filter Cutoff
A series of eight available input filters – filters are hardware and
software – allow you to choose the best rolloff frequency for input
channels on your I/O module. When choosing a filter, remember that
time frequency rolloff may affect your input signal’s accuracy.
For example, in configuration word 0, if you choose the fastest time
frequency of 600Hz (hardware filter only), little noise is added, but the
slowest frequency of 0.2Hz will provide the most accurate process
noise filtering. See below to decide which input filter to use in your
application:
Bits 00-03
Sensor Type (Thermocouple or RTD)
RTD Type
Bit
03
02
01
00
Sensor type for channels 0 through 3
0
0
0
0
Resistance (default)
0
0
0
1
100 ohm Pt
α
= 0.00385 Euro (–200 to +870°C)
0
0
1
0
200 ohm Pt
α
= 0.00385 Euro (–200 to +400°C)
0
0
1
1
100 ohm Pt
α
= 0.003916 U.S. (–200 to +630°C)
0
1
0
0
200 ohm Pt
α
= 0.003916 U.S. (–200 to +400°C)
0
1
0
1
100 ohm Nickel (–60 to +250°C)
0
1
1
0
200 ohm Nickel (–60 to +200°C)
0
1
1
1
120 ohm Nickel (–80 to +320°C)
1
0
0
0
10 ohm Copper (–200 to +260°C)
1001 through 1111 not used
Bits 00-03
Thermocouple Type
Bit
03
02
01
00
Sensor type for channels 0 through 3
0
0
0
0
mV (default)
0
0
0
1
B
300 to 1800°C
(572 to 3272°F)
0
0
1
0
E
–250 to 1000°C
(–418 to 1832°F)
0
0
1
1
J
–210 to 1200°C
(–346 to 2192°F)
0
1
0
0
K
–250 to 1372°C
(–418 to 2502°F)
0
1
0
1
L
–200 to 800°C
(–328 to 1472°F)
0
1
1
0
N
–250 to 1300°C
(–418 to 2372°F)
0
1
1
1
R
–0 to 1768°C
(32 to 3214°F)
1
0
0
0
S
–0 to 1768°C
(32 to 3214°F)
1
0
0
1
T
–250 to 400°C
(–418 to 752°F)
1010 through 1111 not used