Wireless E-stop required functionality on loss of signal
Wireless E-stop required functionality on loss of signal
(OP)
Could one of you point me to the right code / rule regarding wireless E-stop functionality?
Specifically - can a button be labeled "E-stop" on a wireless remote, if the system is designed to NOT shut down on event of a wireless failure? I am not seeing in NFPA 79.
I ask because the other wireless systems I have seen all are fail-safe, if any remote is not working the system will not operate. My system differs and I want to label it correctly / legally.
Electrical rating of my equipment in question is NEC C1D1. We have traditional hardwired E-stop buttons elsewhere in the system.
Thanks for any code references you can provide.
Specifically - can a button be labeled "E-stop" on a wireless remote, if the system is designed to NOT shut down on event of a wireless failure? I am not seeing in NFPA 79.
I ask because the other wireless systems I have seen all are fail-safe, if any remote is not working the system will not operate. My system differs and I want to label it correctly / legally.
Electrical rating of my equipment in question is NEC C1D1. We have traditional hardwired E-stop buttons elsewhere in the system.
Thanks for any code references you can provide.





RE: Wireless E-stop required functionality on loss of signal
However, as a secondary system, if wireless is unreliable, the you'd be getting a truckload of false shutdowns, if the system does as you suggest.
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: Wireless E-stop required functionality on loss of signal
But being Cl1 Div 1, are you sure you are not thinking of an ESD (Emergency Shut Down) system rather than "E-Stop" in the more traditional machinery safety sense? Different systems and applications. ESD as typically implemented in the Oil/Gas/Petrochemical industry is more about executing an ORDERLY controlled shutdown PROCESS, not "Emergency Stop", because immediately stopping something can be more dangerous on a wider scale. So an ESD system receiving a wireless signal from an ESD switch that loses the wireless connection would have multiple levels of redundancy to ensure that the loss of that signal doesn't trigger a shut down needlessly. If that's what you are thinking of, using the term "E-Stop" may be what's tripping you up.
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: Wireless E-stop required functionality on loss of signal
RE: Wireless E-stop required functionality on loss of signal
You're 1st paragraph is spot on with my concern - is there a legal or otherwise requirement for the term "E-stop" to be fail safe? I want to know if we can or should call the button "E-stop" on the remote. If the wireless connection fails, we do NOT want it to automatically stop. The operator would just have to use the local controls.
Again I'm really just looking for the right code that defines this required behavior. Anyone know which code I need to look at?
RE: Wireless E-stop required functionality on loss of signal
I am still curious if wireless e-stops are governed by code somewhere.