Stop means stop
Write an emergency stop that needs a separate, deliberate reset before anything can start again.
Make the emergency stop cut the robot's power at once, and make sure that twisting it out again restarts nothing. Only a fresh press of Reset re-arms the cell, and only Start runs the robot.
Training only. This is not a certified safety system. On a real machine these rules run in a safety relay or a safety PLC, designed and validated to ISO 13849-1 or IEC 62061.
Pro missionReset, then Start
Test 1 of 5StartInputOFFResetBlue Reset button, outside the fenceOFFEStopAInputONK1Contactor K1: ON closes it (power to the drive)ON- Level
- Applied
- Time
- About 25 min
- Reward
- +300 XP
- Rig
- 3D robot safety cell
- Siemens editors
- Ladder (LAD), SCL
- Rockwell editors
- Ladder, Structured Text
- Beckhoff editors
- Structured Text
- Course stage
- 32. Safety lab 1: stop, and restart only on purpose
What the tests check
- The E-stop switches K1, K2 and DriveRun OFF in the same .
- Releasing the E-stop restarts nothing.
- Reset closes K1 and K2 but never sets DriveRun.
- Reset and Start only count on a fresh press, never a held button.
- ResetLamp is ON while a reset is needed and possible.
- Try it Use the buttons below the model and watch the rig respond.
- Test solution Every check runs on your code in one press.
- Replay If one fails, step through it one scan at a time to see why.
Where you’d see this on site
Every machine with an emergency stop has this rule. The button latches in, and twisting it out only allows a restart.
If releasing the E-stop restarted the robot, whoever let it go could be hit by the arm. Separating reset from start means a person decides to restart, with the cell in view.
A robot stacks cartons inside a fence. A gate lets a fitter in, a light curtain lets the cartons in, and an emergency stop sits outside. Two contactors in a row cut the robot's power, so one that sticks cannot keep it running.
- InfeedCartons through the curtain
- PickRobot takes the carton
- GuardStop, reset, restartYou are here
- PalletSix cartons, then change
On a real site: places, parts and safety
- Robot palletising and packing cells
- Machine tending: robots loading presses and machine tools
- Any guarded machine with a door, a curtain or an E-stop
Training only: this rig is not a certified safety system. Real safety functions run in safety relays or a safety PLC, designed and validated to ISO 13849-1 or IEC 62061.
IEC 60204-1 sets out stop categories 0, 1 and 2 and how an emergency stop must behave. Which category a machine uses comes from its risk assessment.
The sizes, timings and cutaways are teaching choices, not a drawing of any one real installation.
Next in the course
64Two channels must agreeRead the E-stop and the gate on two channels each, and lock the cell out when a pair disagrees.Advanced · 40 min · +450 XP
65Both hands, checked twiceAdd checked palm buttons, an emergency stop and a reset to the two-hand press.Advanced · 45 min · +500 XP- 66Prove the contactors let goCheck the contactors' mirror contacts, and refuse a reset while one is welded shut.Advanced · 40 min · +450 XP
- 67Stop dead or slow downMake the E-stop a category 0 stop and the gate a category 1 stop: brake first, then cut the power.Advanced · 40 min · +500 XP