IP Rating

Reading the two digits

The digits are independent and each has its own scale.

First digit — solids, 0 to 6. Level 5 is dust-protected, meaning limited ingress that does not interfere with operation. Level 6 is dust-tight.

Second digit — water, 0 to 9. The steps that matter for e-bike packs:

• 4 — splashing water from any direction
• 5 — low-pressure water jets from any direction
• 6 — powerful water jets
• 7 — temporary immersion

So IP55 is dust-protected and jet-resistant at low pressure; IP65 is dust-tight with the same water rating. A higher first digit does not imply better water resistance, and vice versa.

Where the scale is misleading

The water levels are not a simple ladder. IPX7 (immersion) does not imply IPX5 or IPX6 (jets) — they are different tests, and an enclosure certified for immersion has not necessarily been tested against pressurised spray. Where both matter, both must be stated.

Ratings are also tested with fresh water in a laboratory, at a defined temperature and duration. They say nothing about pressure washers at close range, road salt, or repeated thermal cycling — all of which an e-bike pack meets in real service.

Choosing a level

Match the rating to the duty cycle rather than buying the biggest number:

• IP54 to IP55 — consumer bikes stored indoors. Our 48V packs are IP55 as standard.
• IP65 — delivery fleets, rental operations, and cargo bikes that stay mounted outdoors and get washed down.

Higher sealing costs more and complicates servicing, and a fully sealed enclosure has to manage internal pressure as the pack heats and cools.

Specify the rating at enquiry stage. Sealing is an enclosure design decision, not a finishing step, and raising it after sample approval usually means new tooling.