Protective stop
A stop triggered automatically by a safeguard, such as an interlocked gate or a safety sensor, rather than by a person pressing an emergency stop.
The network analogy
An automatic err-disable triggered by a monitored condition, as opposed to an administrator shutting a port by hand.
Why it matters for wireless
ODVA notes that missed or delayed safety packets can activate the safety function, so on robots and vehicles a wireless dropout can cost a stop and a restart even though no person or safeguard asked for one.
Robot safety requirements distinguish a normal stop, a protective stop, and an emergency stop, with the protective stop activated by interlocks or safety sensors. One robot vendor calls its version a safeguard stop: it comes from an external protective device, uses stop category 2 with power retained and the position held as a monitored standstill1, and resets automatically or manually depending on the risk assessment. OSHA lists protective stop among the safety functions a robot application may need.
Names, stop categories, and reset behavior vary by vendor and standard. Read the device’s own documentation for what its protective stop does and how it recovers.
About this page
Built from 4 sources: 1 regulator or government source, 1 protocol owner or alliance and 2 vendor documents. Researched and drafted with AI assistance, then reviewed and approved by Ben Rutter on . How pages are made
- First published
- Last updated
Cite this page
Plain
Ben Rutter. "Protective stop." OT Wireless, published October 5, 2026. https://otwireless.com/glossary/protective-stop/
APA 7
Rutter, B. (2026, October 5). Protective stop. OT Wireless. https://otwireless.com/glossary/protective-stop/
BibTeX
@misc{rutter2026protectivestop,
author = {Rutter, Ben},
title = {{Protective stop}},
year = {2026},
howpublished = {\url{https://otwireless.com/glossary/protective-stop/}},
organization = {OT Wireless},
}