I have 4 in 1 emax 30a esc but one of them not work
Can i use any 30a esc with that esc ??

[Admin Edit] Topic name changed to reflect the content of the thread. Avoid ambiguous titles such as "Need your help".

Please be a little clear.......
What is a "4 in 1 emax 30a esc"?
and; " any 30a esc with that esc ?"
Regards

Yes i want to use that remaining 3 working esc of 4 in1 and 1 another 30a esc

That's the problem with 4-in-1s. I read that replacement modules are available but its hard to get in India.

As for mixing ESCs, you can try that but there is no guarantee that it would work. See https://oscarliang.com/use-different-brand-esc-together-copter/

Oh I get it,
4 ESCs in 1
I haven't heard that before and never seen that before either.
So I am helpfullness-less now.
Sorry.
Regards