FattyArbuckle
Member
I have two questions regarding E-Stop usage.
For 10+ years I have incorporated two ?rules? regarding E-Stops.
Can anyone provide code information (NFPA, IEEE, NEMA, OSHA, etc.), and paraphrase the code if you have time, to support my approach?
Thanks!
For 10+ years I have incorporated two ?rules? regarding E-Stops.
- E-Stops cannot be used as a standard stop button. The thought is that this defeats the purpose with regards to training employees. If it is an emergency we want employees to act appropriately and have trust that the equipment will act appropriately with an immediate response by stopping and controlling energy sources.
Does any code prohibit an E-Stop being used as a regular cycle-stop button?
--------------- - In Europe (and maybe other areas) they have safety-rated Variable Frequency Drives (VFD?s). My understanding is that USA code requires the removal of power from non-safety rated VFD?s in an E-Stop condition ? the VFD software cannot be used to assure equipment stoppage. (I don?t think any USA code addresses safety-rated VFD?s yet.) This of course, requires a relay before the VFD.
Are we required by code to remove power from a VFD under E-Stop (as we cannot rely upon software in an emergency condition) ?
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Can anyone provide code information (NFPA, IEEE, NEMA, OSHA, etc.), and paraphrase the code if you have time, to support my approach?
Thanks!