can I replace Diode number MM30FU120B with Diode Number RHRG75120?

Datasheets are attached

thanks in advance

 

Maybe.
It depends on how important the reverse recovery time is to the operation of the circuit.

 

It should work. What is confusing is that neither of the pictures look like high power diodes.

 

It should work. What is confusing is that neither of the pictures look like high power diodes.

It is high power doide, 1200v , 30A
And 1200v, 75A is the RHRG
What parameters most important for you to look in datasheet of both doides? And know that it should work?

 

By the way, after I made that post , I searched in old Pcb for UPS , as the device is UPS with capacity of 10kva,
I’ve found APT30D120B, it looks similar, and datasheet and parameters are close, even I think this one is better quality thank the Mm30fu120b
I installed this one, and the machine worked fine, without load
I will have to load and see if there is any problem or to see this doide will withstand the load and ampere

 

The critical diode parameters are peak reverse voltage, average forward current, and peak forward current. after that come power dissipation, temperature, and switching time.