On Tuesday 03 May 2016 05:30:54 andy pugh wrote: > On 3 May 2016 at 10:14, Nicklas Karlsson <nicklas.karlsso...@gmail.com> wrote: > > If Solid State Relay SSR happen to be a thyristor it will only allow > > a limited dv/dt or it will fail to turn off. A common source of > > dv/dt is inductive or maybe capacitive load and it happens because a > > thyristor turn off at zero current although a reactive load do not > > have zero voltage at zero current. Problem is circumvented by a > > properly sized capacitor in parallel to limit voltage rise during > > turn off. > A dv/dt failure is usually destructive.
> How would one determine "properly sized"? That is a big compromise because that capacitor is a leakage across it, enough to knock you around if its over done. A.02 u-f, 1 kv ceramic might help. But you'll probably feel a buzz if you get across it. > And does the "fail to turn off" problem description include not > turning off ever again, even when removed from the circuit and from > all power? Generally yes, its an avalanche mode failure that shorts the switching junction. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
