[walkabout]

Howdy... I have a 90 volt DCPM motor,1/3 hp, and rated for 1750 RPM. I realize there are these cheap SCR bridge controllers available. They can generate 90 VDC via an SCR diode bridge. Just wondering out-loud if could leverage this 90 VDC from the unit for an external h-bridge circuit? The h-bridge would merely behave as an external switch for the 90 VDC to the motor using mosfets drivers. I'd like to use the h-bridge if possible as it has more features. Anyone have any thoughts on this? Much oblige...

[Al_The_Man]

You can pay a little extra and get the KB/Baldor PWM version?
Modifying the SCR type for H-bridge would hardly be practical, IMO, there are Chinese versions out there that PWM the 120Hz ripple, but it is still relatively low frequency switching.
Al.

[walkabout]

Thanks for your response. BTW, Just curious... You said:
"there are Chinese versions out there that PWM the 120Hz ripple"
I guess I do not understand that. Can you point me to a resource that explains this a bit better? (Or a manufacturer of such a product)