Rockwell Automation System Design for the Control of Electrical Noise - Manual (Page 83)

Publication GMC-RM001A-EN-P — July 2001
High Speed Registration Inputs 9-7
Dual Voltage Inputs (24V or 5V)
Where the input is split into 5V and 24V, with inputs sharing the same
common, it is important that the 5V input is not left floating. In the
figure below, the 24V and 5V inputs are shorted together and fed at
5V.
Figure 9.5
Registration filter circuit (24V/5V)
The on-delay and off-delay times are shown in the table below.
R1
R2
C
+5V
+24V +24V
Common Common
To Registration Inputs From Detector
R1
k ohm
R2
k ohm
C
nF
Delay
On
µ
s
Delay
Off
µ
s
Noise
Attenuation
factor
@ 1MHz Noise
Attenuation
@1MHz
dB
0.100 0.390 220 22 2 14 23
0.100 0.390 220 22 5 30 29
0.100 0.390 220 22 10 65 36
0.100 0.390 220 22 22 139 43
0.100 0.390 470 47 47 295 49
0.100 0.390 1000 100 100 649 56