If any of you have a Case of Corrona, I hope it is the type that comes in bottles or cans.
First, there is a guy in this group who I chatted with in the past who is like an expert in the E-Stop function. He has a Blog or Website dedicated to this topic which I cannot currently find. Can anyone help me get in contact with him? My area of need is with integrating the E-Stop function with a Variable Frequency Drive (inverter). I have to meet the international requirements as well as the USA and Canadian requirements. What I have is 3-phase AC power, through a Contactor, to a VFD, which powers a 3-phase motor. The VFD has the motor brake feature built in. Under a normal STOP command, the VFD engages the motor brake. All is fine. The VFD manufacturer's documentation shows to connect the E-STOP to the motor Contactor which OPENs power to the VFD. When the E-Stop is engaged, power to the VFD is shut down; the motor continues to spin for up to 30 seconds or more before coming to a stop. The motor Brake does not engage because it is a feature of the VFD which is powered down. This makes no sense to me. The E-STOP is supposed to stop motion as quickly as possible without causing additional Risk (according to the MD and NFPA 79 cat.2). So how is the E-Stop function supposed to work with a VFD? How is this typically done? Are we buying the wrong VFD? Thanks to all. The Other Brian - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
