IP51 vs IP59K
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP51 and IP59K are both IEC 60529 ingress protection codes, but they differ in liquid protection (level 1 vs 9K). IP51 is rated for dust-protected and vertically dripping water, while IP59K provides dust-protected and high-pressure, high-temp water jets.
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.
The IP59K classification guarantees dust-protected (limited ingress, no harmful deposit) and resistance to high-pressure (8–10 MPa), high-temperature (80 °C) water jets. It is an IEC 60529 ingress protection code combining first-digit (solid) level 5 with second-digit (liquid) level 9K.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP51
5 — Dust-Protected
IP59K
5 — Dust-Protected
Liquid protection (second digit)
IP51
1 — Vertically Dripping Water
IP59K
9 — High-Pressure, High-Temp Water Jets
Dust-tight
IP51
Limited
IP59K
Limited
Water-jet resistant
IP51
No
IP59K
Yes
Submersible
IP51
No
IP59K
Yes
Outdoor suitable
IP51
No
IP59K
Yes
The exact difference (IP51 vs IP59K)
Solid protection
IP51
Level 5 — Dust-Protected
IP59K
Level 5 — Dust-Protected
Both IP51 and IP59K share the same solid protection: Dust-Protected.
Liquid protection
IP51
Level 1 — Vertically Dripping Water
IP59K
Level 9 — High-Pressure, High-Temp Water Jets
IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water), while IP59K handles 8–10 MPa (High-Pressure, High-Temp Water Jets). IP59K provides 8 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP59K offers higher overall protection than IP51. Choose IP59K for harsher environments; IP51 may suffice for milder conditions and can be more cost-effective.