UL 2743 vs UL 9540: what a listing covers and does not

Where one standard ends and the next begins

Intertek's standards notice for UL 2743, titled Portable Power Packs, adds a scope clause 1.7. Power packs above a set capacity are not covered by UL 2743. They fall under UL 9540, Energy Storage Systems and Equipment. The thresholds sit in Table 1.1.

The notice speaks of aggregate capacity. It does not say how an expansion pack is counted. So a printed system size above 20,000 Wh is a question to put to the maker. Jackery's Explorer 5000 Plus lists 30,240 Wh with its packs. Anker's S5000 lists 30,144 Wh. EcoFlow's DELTA Pro Ultra lists 30,720 Wh per inverter. Each is about 1.5 times the 20 kWh line. Bluetti's AC200L and Anker's F3000 both top out at 12,288 Wh, about 61 percent of it.

What UL 2743 tests

The notice lists the new items in the newest edition, and they show the scope. AC outlets on a power pack must be NEMA types rated 120 V and 15 A. Grounded 30 A types are allowed only with double insulation or ground-fault protection. Accessible output parts are limited to 240 VA, checked by an energy hazard measurement test.

A lithium-ion pack above 1 kWh gets a thermal propagation test and extra marking. The overview list also names a definition of "portable or moveable" and a mass limit for the stability test. It lists a strain relief test for the interconnecting cable and updates to the impact and drop tests. The list gives a fuller picture of what the standard checks on a finished unit. Intertek says reports not updated to the newest edition are withdrawn, so an older listing may refer to an earlier set of tests.

UL 9540 has its own scope and tests, which the notice points to without describing. A buyer comparing two stations should read the standard's name as a pointer to a test program. It is not a score or a rank. Two products that both print UL 2743 were tested against the same document, and nothing more follows from that.

What stations print

Makers name different standards, and a name alone does not say which edition or which configuration was tested. Anker's pages for the S5000 and the F3000 print UL 9540, and the S5000 adds UL 9540A. Bluetti's AC200L prints UL 2743, and its system tops out at 12,288 Wh with packs, below the 20 kWh line. Jackery's Explorer 100 Plus prints UL 62368-1. Its Explorer 240 v2 names UL 1778 for the UPS function. Those are different standards again.

What a listing leaves out

A listing names a product and a standard. Whether it reaches panels, cables or another brand's pack is a question for the maker. The notice only describes tests on the power pack itself.

Transport has its own rule. 49 CFR 173.185 requires each lithium battery to be of a type proven to meet UN 38.3 criteria. That holds whether or not its cells were of a tested type. A UL listing and a transport test are separate pieces of paperwork.