Rockwell Automation Publication 440R-UM013G-EN-P - December 2022 63
Chapter 11 Troubleshooting
As the example shows, long wires are not a likely cause of safety input issues.
Channel Simultaneity (Discrepancy)
GSR safety relays have infinite simultaneity (sometimes referred to as discrepancy). One
channel can close (at T1) and the other channel can close much later (at T2), and the input
circuit is satisfied. The order in which the channels close is not significant; either channel can
close before the other (see Figure 70
).
Figure 70 - GSR Safety Relays Have Infinite Simultaneity (Discrepancy)
Multiple-channel Cycling
GSR safety relay inputs are not satisfied if one channel turns on and off multiple times,
followed by the closure of the second channel (see Figure 71). The input status indicator
remains red. This condition is not shown as a fault condition by the PWR/Fault status
indicator. To clear this condition, open both channels and then reclose them.
Figure 71 - Multiple Cycles on One Channel Are Not Allowed
Table 17 - Wire Resistance
ISO Cross Section [mm²] AWG Ω Per 1000 m Ω Per 1000 ft
0.33 22 52.94 16.14
0.5 20 33.30 10.15
0.75 18 20.95 6.386
1.5 16 13.18 4.016
2.5 14 8.28 2.525
4125.211.588
Channel 1
Channel 2
Open
Closed
Open
Closed
Time
Time
Channel 1
Channel 2
Open
Closed
Open
Closed
Time
Time
To Next Page
Loading...
Need help?
General
