IP35 vs IP51
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP35 and IP51 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 3 vs 5) and liquid protection (level 5 vs 1). IP35 is rated for > 2.5 mm — tool / wire and water jets (6.3 mm nozzle), while IP51 provides dust-protected and vertically dripping water.
Built to withstand protection against solid objects larger than 2.5 mm and protection against water jets. Water projected by a 6.3 mm nozzle against the enclosure from any direction shall have no harmful effects.. Classified as IEC 60529 ingress protection code IP35, it pairs solid level 3 with liquid level 5.
With IP51, an enclosure receives dust-protected (limited ingress, no harmful deposit) and protection against vertically falling drops of water. Dripping water shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 5 with second-digit (liquid) level 1.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP35
3 — > 2.5 mm — Tool / Wire
IP51
5 — Dust-Protected
Liquid protection (second digit)
IP35
5 — Water Jets (6.3 mm nozzle)
IP51
1 — Vertically Dripping Water
Dust-tight
IP35
No
IP51
Limited
Water-jet resistant
IP35
Yes
IP51
No
Submersible
IP35
No
IP51
No
Outdoor suitable
IP35
Yes
IP51
No
The exact difference (IP35 vs IP51)
Solid protection
IP35
Level 3 — > 2.5 mm — Tool / Wire
IP51
Level 5 — Dust-Protected
IP35 provides "> 2.5 mm — Tool / Wire" (level 3), while IP51 provides "Dust-Protected" (level 5). IP51 is 2 levels higher.
Liquid protection
IP35
Level 5 — Water Jets (6.3 mm nozzle)
IP51
Level 1 — Vertically Dripping Water
IP35 handles 30 kPa (Water Jets (6.3 mm nozzle)), while IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water). IP35 provides 4 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP35 offers higher overall protection than IP51. Choose IP35 for harsher environments; IP51 may suffice for milder conditions and can be more cost-effective.