UPS and EPS switchover times: what under 20 ms means

A figure and a disclaimer in one document

Jackery prints a 20 ms switchover for the Explorer 1000 v2. The same station carries the line "This product does not support 0ms switching." Both statements stand together. A 20 ms switchover is a short gap, and 0 ms means none at all. A switchover figure only means something alongside the word that comes with it.

What each maker prints

Makers use three labels, UPS, EPS and basic UPS, and attach them to different times.

Jackery's older Plus and Pro stations call the same function EPS and list 20 ms for it. EcoFlow's RIVER 3 manual separates two models. One has a 10 ms UPS. The other transfers within 20 ms and is labeled EPS. So one brand can sell the same station size with different labels, and the label tracks the switching time.

Standby and online modes

Larger stations print two modes and two times. The Explorer 5000 Plus lists a backup UPS under 20 ms and an online UPS at 0 ms. It says the online mode has to be switched on in its app. Bluetti prints a similar split on its AC300, with no delay for online UPS and 20 ms from standby.

The word online does not always bring 0 ms. The DELTA 3 prints a standby UPS at 10 ms. Its larger DELTA 3 Max prints an online mode at the same 10 ms. Count the number, not the mode name.

Across the four brands, the printed times cluster in a few steps. Of 74 stations that print a switchover time, 35 list 20 ms, 30 list 10 ms, 5 list 30 ms and 4 list 15 ms. Five EcoFlow models account for all of the 30 ms entries. They run from the RIVER 2 line to the DELTA 2 and the original DELTA Pro.

Wording also shifts between documents from one maker. Anker's C300 manual says under 10 ms, while its spec page says 10 ms. Jackery's pages describe some stations as under 20 ms and others as 20 ms. Treat 10 ms and under 10 ms as the same class of backup.

What the number does not say

EcoFlow's own article draws the line plainly. It calls EPS the emergency mode for loads that tolerate a brief interruption. It says a true UPS is often under 10 ms. It states that computers hold charge in capacitors for only a few milliseconds. It also says 20 ms is the figure generally acceptable, and that EPS timing sits at the edge of what most computers tolerate.

Those are the maker's statements about typical equipment. A station's spec cannot see what a particular device will accept. The device's own manual gives its ride-through time, and EcoFlow's checklist ends with a live test under a real load. A station that lists 10 ms is faster than one that lists 30 ms. Neither listing says anything about a specific load.