IP56 vs IP51
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP56 and IP51 are both IEC 60529 ingress protection codes, but they differ in liquid protection (level 6 vs 1). IP56 is rated for dust-protected and powerful water jets (12.5 mm nozzle), while IP51 provides dust-protected and vertically dripping water.
IP56 is dust-protected and resists powerful water jets (12.5 mm nozzle, 100 kPa). Suited to outdoor equipment subjected to heavy rain or hose-directed water.
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)
IP56
5 — Dust-Protected
IP51
5 — Dust-Protected
Liquid protection (second digit)
IP56
6 — Powerful Water Jets (12.5 mm nozzle)
IP51
1 — Vertically Dripping Water
Dust-tight
IP56
Limited
IP51
Limited
Water-jet resistant
IP56
Yes
IP51
No
Submersible
IP56
No
IP51
No
Outdoor suitable
IP56
Yes
IP51
No
The exact difference (IP56 vs IP51)
Solid protection
IP56
Level 5 — Dust-Protected
IP51
Level 5 — Dust-Protected
Both IP56 and IP51 share the same solid protection: Dust-Protected.
Liquid protection
IP56
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP51
Level 1 — Vertically Dripping Water
IP56 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)), while IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water). IP56 provides 5 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP56 offers higher overall protection than IP51. Choose IP56 for harsher environments; IP51 may suffice for milder conditions and can be more cost-effective.