IP51 vs IP56
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP51 and IP56 are both IEC 60529 ingress protection codes, but they differ in liquid protection (level 1 vs 6). IP51 is rated for dust-protected and vertically dripping water, while IP56 provides dust-protected and powerful water jets (12.5 mm nozzle).
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.
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.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP51
5 — Dust-Protected
IP56
5 — Dust-Protected
Liquid protection (second digit)
IP51
1 — Vertically Dripping Water
IP56
6 — Powerful Water Jets (12.5 mm nozzle)
Dust-tight
IP51
Limited
IP56
Limited
Water-jet resistant
IP51
No
IP56
Yes
Submersible
IP51
No
IP56
No
Outdoor suitable
IP51
No
IP56
Yes
The exact difference (IP51 vs IP56)
Solid protection
IP51
Level 5 — Dust-Protected
IP56
Level 5 — Dust-Protected
Both IP51 and IP56 share the same solid protection: Dust-Protected.
Liquid protection
IP51
Level 1 — Vertically Dripping Water
IP56
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water), while IP56 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)). 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.