Can I use a UPS or voltage regulation system with an Equi=Tech system?

Yes. However, make sure the Equi=Tech is plugged into the output of the UPS or line voltage regulator, never the other way around. Also, it important that the UPS or voltage regulation equipment has at least a 50% higher capacity than the Equi=Tech system or that the UPS can drive a 100% transformer load at its rated output.