MCCB Trip by Emergency Stop Button

It depends upon what the Instruction Manual that was supplied with it says. It cannot be seen from here.

in mccb testing point are there.. if any emergency cases used by this testing switch.

MCCB make and part number is the main needed info to give a valid answer ....

MCCB make- Scheider Model no.- CVS 250F

• So what does it say in the manual that came with it?
• If the manual has been lost then has a search been done on the internet to find another one?
• Has a call been put in to <...Schneider...> to ask the question?

Sheesh.

In general though, MCCBs can be remotely tripped in two ways: Shunt Trip (ST) or Under Voltage Release (UVR). But rather than focus on whether or not you can, start with whether or not you SHOULD. Using remote tripping of a protective devie is not considered best Practice in most engineering circles, here is why.

Using the ST option is not "fail safe". If you are relying on this for emergency shut down (ESD) as a safety function, you must consider what happens if a wire is broken or disconnected. In the case of a Shunt Trip coil that must be ENERGIZED to make the MCCB trip open, a broken wire results in NO SAFETY OPERATION and is therefor contraindicated.

Using the UVR for ESD is more fail safe, but comes with another nasty side effect. EVERY time you lose power, the MCCB goes into a tripped state. This can result in unwanted resetting procedures that can result in frustration that leads to tampering. it can also cause the MCCB to wear out prematurely, they are not really designed to be used as a contactor.

There are some MCCBs with a coil, which trips the device whenever it looses power (I've seen 'em for 24VAC) you can use this coil to interlock the breaker, either to safety guards, control cabinet doors, or emergency stops. It works the opposite way to the one you describe as Shunt Trip.

They are fast and reliable and don't interfere with the thermo-magnetic trip function.

They have been around for a while.

• "There are some MCCBs with a coil, which trips the device whenever it looses power (I've seen 'em for 24VAC)"

Yes, that is the Under Voltage Release (UVR) I described above. But like I said, it trips EVERY time power is lost.

No, the one I say is not monitoring the supply line voltage (thats the UVR option) it is just a 24VAC coil that trips the breaker when de-energized.

I checked another document besides the one I provided a link for earlier, the manufacturers seem to describe their function in different ways, maybe the device performs the same but the text is a bit confusing.

Anyway, the ones I've seen don't leave you unprotected when a wire (of the coil) is broken, on the contrary they trip right away. I just can't remember the brand and model, but is a little late for that, the OP has already purchased the breaker...

By the way, we should ask the OP the brand and model.

MCCB make- Scheider Model no.- CVS 250F

If it is fitted with or has an option for a remote trip function (or similar) you can. If not then the only way is some sort of crowbar circuit, but this is not recommended due to the assumed distribution class high fault current level (so much so that i am not supplying a link on what a crowbar circuit is).

What does the MCCB manual say?

use a motorised MCCB.

Use an RCCB and create an imbalance by adding a load using the Emergency stop switch. You can use as many Emergency Stop switches and don't need any additional wiring. Use earth connection on the other end of the load used to create the imbalance.

You can also lay a separate single return wire(neutral) bypassing the RCCB for creating the imbalance and tripping the RCCB.

Gajanan Phadte

Use UV coil, and connect NC Emergency stop switch in Series of its supply. You can also providing single phasing, reverse phasing protection by using UV coil