The main difference is that a VDC (Voltage Dip Compensator) protects against momentary voltage sags whereas DPI (Dip Proof Inverter) protects against voltage interruptions (zero volts) AND momentary sags.
Voltage Sag Support
DPI support zone
Voltage Sags to Interruptions (zero volts)
More DPI info
VDC support zone
protects against Voltage Sags
More VDC info
Sag:A short-term decrease in voltage lasting anywhere from milliseconds up to a few seconds.
A very short loss of utility power that lasts up to 2 seconds.
Not sure what kind of voltage fluctuations your facility experiences?
Information:Difference between VDC and DPI (878.29 K)
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