IP16 vs IP51
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP16 and IP51 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 1 vs 5) and liquid protection (level 6 vs 1). IP16 is rated for > 50 mm — back of hand and powerful water jets (12.5 mm nozzle), while IP51 provides dust-protected and vertically dripping water.
IP16 is an ingress protection code that ensures protection against solid objects larger than 50 mm and protection against powerful water jets. Water projected in powerful jets by a 12.5 mm nozzle against the enclosure from any direction shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 1 with second-digit (liquid) level 6.
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)
IP16
1 — > 50 mm — Back of Hand
IP51
5 — Dust-Protected
Liquid protection (second digit)
IP16
6 — Powerful Water Jets (12.5 mm nozzle)
IP51
1 — Vertically Dripping Water
Dust-tight
IP16
No
IP51
Limited
Water-jet resistant
IP16
Yes
IP51
No
Submersible
IP16
No
IP51
No
Outdoor suitable
IP16
Yes
IP51
No
The exact difference (IP16 vs IP51)
Solid protection
IP16
Level 1 — > 50 mm — Back of Hand
IP51
Level 5 — Dust-Protected
IP16 provides "> 50 mm — Back of Hand" (level 1), while IP51 provides "Dust-Protected" (level 5). IP51 is 4 levels higher.
Liquid protection
IP16
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP51
Level 1 — Vertically Dripping Water
IP16 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)), while IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water). IP16 provides 5 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP16 offers higher overall protection than IP51. Choose IP16 for harsher environments; IP51 may suffice for milder conditions and can be more cost-effective.