Allen-Bradley 440R-GL2S2P - Sequence Diagram; Sequence Steps

50 Rockwell Automation Publication 440R-UM012E-EN-P - November 2018
Chapter 9 Example Operational Sequence Diagrams
Sequence Diagram
Figure 43 shows the sequence of operations. This diagram assumes that all
components are operating properly and no faults are present.
Figure 43 - Operational Sequence for Delayed Unlock with Auto Reset
Sequence Steps
The following steps describe each of the highlighted points in Figure 43.
1. 24V DC power is applied to the safety system. The safety devices
perform their internal tests.
2. The GLP safety relay begins its Frequency Measurement Time to check
the proximity sensor speed.
3. After the GLP safety relay determines the speed is below the SLS2
setting, the X14/X24/L11 outputs turn ON and the unlock delay timer
starts. If the proximity sensor speed is greater than SLS1 upon power-up,
the GLP safety relay keeps the gate locked and maintains its outputs in
the OFF state.
4. The 51/L61 outputs turn ON and unlock the gate.
5. You press the Start button. The machine begins to accelerate and the
proximity sensors generate pulses.
Power
Operator Location
Gate Status
L11
Y32
Unlock
Delay
On
O
Locked
Unlocked
24V
0V
24V
0V
Closed
Open
24V
0V
24V
0V
X14, X24
(K3... K4)
24V
0V
Lock Signal
(51/ L61)
24V
0V
EM Ouputs
(K5...K8)
Start Button
(not shown)
Stop Button
(not shown)
Safely Limited Speed
Operator
In Cell
In Cell
Out of Cell
Gate is unlocked
Gate is unlocked
LockedGate is lockedGate is locked
24V
0V
Proximity Sensors
Unlock
Delay
Frequency
Measurement
Time
Frequency
Measurement
Time
K1... K2
24V
0V
1 2 3 4 5 6 7 8 9 10 11 12
Unlock Lock