Andy, This isn't the worst thing I've seen. Rs485 is a two wire differential half duplex signalling system. The doc says that it can run up to 38.4kbps.
So you one 1 wire to the plus of the master and the vfd and the other wire to the minus. It will run on anything twisted that is better than tin cans and wet string. Ground one side of the shield if there is one. Set the master and slave to the same baud rate (38.4k). What are you planning on using for the RS485 master interface? You can get things that shift levels from rs232 serial or you can get boxes that sit on a network and talk rs485 out the back. I use the network ones personally. Are you familar with talking modbus? There is an address for each slave, them a command (usually read register or preset register,) then the start and range of registers, then the data (either there or back) and finally a CRC16. All the stuff is sent as 8 bit data as two hex characters encoded in ascii. The idea is that the master sends out the data and then the slave responds. No one talks without the master talking first. I would assume the numbers in the document (like 12-00) is the modbus register address. It can take a little trial and error to get this right. I hope that helps. jerry On Mon, Feb 8, 2016 at 2:03 PM, andy pugh <bodge...@gmail.com> wrote: > On 8 February 2016 at 21:42, Bertho Stultiens <ber...@vagrearg.org> wrote: > > > Try and try again, or get a hold of the documentation. ;-) > > The documentation is silent on the subject: > > http://www.lovatoelectric.com/Single-phase-supply-200-240VAC-50-60Hz-EMC-suppressor-built-in-PNP-24VDC-programmable-inputs/150005010/spd > > > -- > atp > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > > > ------------------------------------------------------------------------------ > Site24x7 APM Insight: Get Deep Visibility into Application Performance > APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month > Monitor end-to-end web transactions and take corrective actions now > Troubleshoot faster and improve end-user experience. Signup Now! > http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Jerry Scharf FINsix IT 650.285.6361 w 650.279.7017 m ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
