Flex IO module HOT Installation

[rlbarras 0]

Can you add a module to a flex io rack while the bus online (processor in RUN)? I know its never recommended to do this, but some families of PLC/Cards are "Hot Swappable"... I have a Prosoft MV194 module I need to add to a remote flex io rack (from a PLC-5). I can't take the bus offline at this time.... so, has anyone ever had experience with this or knows if it can be done? This particular module is externally power, so I'm hoping someone tells me yes. The manual does say "do not install while powered", but I'm not sure if its talking about its external power or bus power... help!!

[Ken Roach 194]

You can insert and remove FLEX modules into the wiring bases while the FlexBux is live, but I have never heard of anyone attempting to add a wiring base while the FlexBus is live. I suspect your chances of doing so successfully are about 20%, which is about the indicence of damage to 1771 chassis when hot insertions are done. If you already have a wiring base in place, you can add the module to it. FLEX modules can be added and removed to live FLEX wiring bases while the adapter and Flexbus are powered. You're supposed to remove the field power to that module only, before you insert or remove it. If the 1794-ASB is not configured already to handle that module (like if it's a 1/2 Rack and you're adding a fifth module) then you won't be able to get the module running. This is for two reasons; because the 1794-ASB only reads the number of attached modules during powerup, and because the scanlist of a PLC-5 RIO channel cannot be changed during runtime.

[rlbarras 0]

Its configured for a 1/2 rack and this would be the fourth base/module. If I were to attempt this, I guess I should plug the base in first then clamp down the module? You think it can damage the existing components?

[ozzium 0]

I would schedule a 1 minute down time, cut the power, put on the module, then power on.

[rlbarras 0]

Sorry I never got back... We cut it over yesterday, I've been offshore at the site since thursday, and yesterday we got a chance to bring the rack down. So, I guess it was a mute point, but I wanted to know if could've been done. All is well and running!!!!... Thanks.