E-Stop CH1/CH2 Pilz — Emergency circuit open — E-stop pressed or wiring interrupted
At a glance
- Severity
- FAULT STOP
- Domain
- SAFETY
- Reference standard
- IEC 60204-1 / ISO 13850
- Product / context
- Emergency stop circuit open
What it means
The emergency stop circuit is open. The machine is in a safe state and cannot be restarted. The opening may be caused by a pressed E-stop mushroom button, a broken wire, or a faulty contact in the safety chain.
Probable causes
- Emergency button pressed and not reset (latching mushroom not released).
- Emergency circuit cable broken or loose connection in the series chain.
- NC contact of the E-stop button worn or oxidized.
- Wiring error in the series chain of emergency devices.
Where to start
Visually check all emergency stop buttons on the machine. Is any one pressed (mushroom in the depressed position)?
Full guided diagnosis in the app
The diagnostic tree for this fault has 7 guided steps with measurements, checks and resolutions. You'll find it in ElectraIQ, one of the five IndexOS apps: free, works offline.
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The same fault on other brands
More Pilz codes
- CH1≠CH2 — Safety relay does not reset — cross-channel fault or contactor feedback
- PSENmag error — Door/guard interlock open — safety limit switch tripped
- PSENopt ERR — Safety light curtain in lockout — alignment or OSSD error
- SYS ERR — Safety PLC in error state — F-CPU passivation