What's the effect of semi-isolation?

[seyyah]

I'll design an h-bridge dc motor controller. I don't want it to cost much so i don't think to isolate all of the control circuit from the power circuit. What i wonder is: Is semi isolation helps anything? I mean, if i only isolate h-bridge driving section from the mcu but not isolate other parts (e.g. current and voltage measuring parts), does this method provide me any protection much or less? Or without isolation can i obtain a reliably operating circuit?
Note: Motor is 24V/300W PMDC motor.

 

[marie65]

isolation advice?

Isolating only the bridge drivers will help you to avoid possible ground loops that can cause a lot of trouble for the measuring electronics.