Faac c721 shorting power on mains

[Gatehelp]

Hi, I have installed a faac c721 with 4 Photocells and everything we connect the transformer it trips the power in the house. We have tested and we get 250v but cannot understand why it keeps shorting the circuit. The c721 is just sat on driveway can't get around it. Has anyone noticed problems with this before - the transformer could just be a smoke screen it's brand new only a couple of weeks old. Faac have said send it back for testing but that's a nightmare with all the blockwork settled back in. I have the nylon racking off also. Any help would be grateful.

 

[DPG]

With this one -

The opener looks like it only takes about 2 Amps.

 

[UNG]

With this one -

I think fitting an RCBO for the gate circuit would have been a better and more prudent option, kitchen socket circuit and a gate circuit on the same RCD could be problematic if the RCD trips, seen it before family go away on holiday and come back to a freezer full of defrosted food because the gate circuit developed a fault

 

[paume70]

Hello, I have a similar problem with a different model of gate opener (FAAC 740d).

The reason for shorting the mains in my case turned out to be a blown circuit board.

Besides having to replace the board I would like to know if there is anything I can do to prevent this from happening again in the future.

My gate opener shares the circuit with other devices and the circuit is downstream a 16A "thermal breaker".

After reading this thread I realize I should had used a 6A instead, but I am still wondering if this alone could had caused the problem.

There is a fuse on the board that is still intact after what could had caused a fire inside the gate opener enclosure.

The transformer also has a suspicious appearance, I don't know if that could had been the cause or a consequence of the meltdown.

I would appreciate if anyone could offer me any ideas of what could had happened.

Thank you

 

[paume70]

C'mon this is an electricians forum, someone has to have some input. The crimped connectors on the 230V input leads, I did that prevent any exposed copper strands. I used a specific tool and they seem to be tight, it is good practice to used these on this type of connector? I am thinking of the possibility of arcing, although I have a working AFDD in my main panel that never triggered.

On another hand I don't know what a transformer should look like, so I can't tell what that streak on the side of the transformer is.

All I've done so far based on the info I found in this thread is to order a 6A breaker besides the replacement for the electronic board.

 

[Moley]

The marks on the transformer are normal. It's where the laminations that make up the core have been welded. The fuse you have shown is on the output side. Has the fuse on the input side blown? It looks like it's under the rectangular white plastic casing next to the L & N markings and next to J4 and marked F1.

 

[paume70]

Thanks for the reply. The fuse on the input side seems to be intact as well. Both fuses are the ones that come with the board and have never been replaced by myself. Does that point at any direction that could explain what has happened here? Thanks

 

[Moley]

As that fuse is okay and looking at the marks on the board I would say that the board has touched the box that it's in and arced to earth. I'm assuming it's a metal box? Was the board fixed in the box or just loose? When you fit the new board make sure you add an earth connection to the plug in 4th photo. Looking at the tracks on the board it looks like the earth connection goes off to either a capacitor or a varistor on the board.

 

[paume70]

The board is screwed onto a plastic back plate and most of it is enclosed inside a see through plastic case. Except for the motor and the screws that hold it onto the bottom plate, i would say the whole enclosure is made out of plastic. The bottom connectors of the board are exposed though, as you can see in the image below.

I will make sure to include the proper PE next to the N and L in the bottom right mains connector.

Thanks for your advice.