OVL led issues!!

[elvis]

Hi all,

I am using Controllino Mega’s digital output to coil an external relay, which actuates a motor contactor of 400V AC supply and maximum load of 7.5 KW. Everytime the the MotorContactor is acutated, the “OVL” led on the Controllino turns red, and stays. I read it is an indication of temperature on the Controllino. Is there any way or tips to resolve this issue, which i am afraid might damage the controllino on the long run.

Thank you,

Elvis Joseph

[mr-controllino]

Hello Elvis,

The first 12 digital outputs of the MEGA are half bridges. They have a nominal current of 2A … and are limited to 3A. If this 3A are reached … the driver chip sets an error. Can only be reseted by a global RESET of the device. Depending on the Version of MEGA you have … this can also be deactivated.

But the much better thing would be to use some of the digital outputs 12-23. They are high side switches and are self-limiting. And they are not able to produce an OVL also with peak currents up to 3, 4, 5A. They are more thermally limited.

So please try to use an output 12-23 and let me know if this solved your problems.

Regards
Marco