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COCT appendix 4 change over switch

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Hi There everyone, 


I hope someone has a definitive answer for this question. Is there an off the shelf product which complies to the requirement of COCT appendix 4 for an suitable interlock changeover switch? I can’t seem to find any off the shelf that complies with everything. I have emailed COCT but they have said they do not have a list of approved change overs. 

If a off the shelf switch does not exist? How do you comply with COCT regulations or how do you get it approved? 

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Thanks, I see this does not have a aux contact to feed back to inverter via an aux contact? As per part b of appendix 4. But if you guys have managed to get it approved with this, then will go this route. 

thanks for your assistance. 

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9 hours ago, MuKi said:

this does not have a aux contact to feed back to inverter

The switch with feedback to the inverter is the internal relay or contactor that the inverter uses to connect the load to the grid when in standby mode.

(This is only applicable for Passive standby UPS used as off-grid SSEG)

The inverter must know the state of this switch (not just based on what it wants the switch to do, because switches can become stuck or welded closed) so that it can never try to power the load from the inverter while the load is powered by the grid.

The Hager changeover switch is just a manual external changeover switch (It is good to have this in your drawing when submitting your application as the people approving them don't know the difference, they just look for a changeover so make sure to label it as such in the drawing)

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