IP21 vs IP47
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP21 and IP47 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 2 vs 4) and liquid protection (level 1 vs 7). IP21 is rated for > 12.5 mm — finger and vertically dripping water, while IP47 provides > 1 mm — small wires and temporary immersion (up to 1 m).
Designed for environments requiring protection against solid objects larger than 12.5 mm and protection against vertically falling drops of water. Dripping water shall have no harmful effects., IP21 is an IEC 60529 code combining solid level 2 with liquid level 1.
IP47 provides protection against solid objects larger than 1.0 mm and protection against the effects of temporary immersion in water. Ingress of water in quantities causing harmful effects shall not be possible.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 4 with second-digit (liquid) level 7.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP21
2 — > 12.5 mm — Finger
IP47
4 — > 1 mm — Small Wires
Liquid protection (second digit)
IP21
1 — Vertically Dripping Water
IP47
7 — Temporary Immersion (up to 1 m)
Dust-tight
IP21
No
IP47
No
Water-jet resistant
IP21
No
IP47
Yes
Submersible
IP21
No
IP47
Yes
Outdoor suitable
IP21
No
IP47
Yes
The exact difference (IP21 vs IP47)
Solid protection
IP21
Level 2 — > 12.5 mm — Finger
IP47
Level 4 — > 1 mm — Small Wires
IP21 provides "> 12.5 mm — Finger" (level 2), while IP47 provides "> 1 mm — Small Wires" (level 4). IP47 is 2 levels higher.
Liquid protection
IP21
Level 1 — Vertically Dripping Water
IP47
Level 7 — Temporary Immersion (up to 1 m)
IP21 handles 0.1 mm/min drip rate (Vertically Dripping Water), while IP47 handles Hydrostatic ~10 kPa at 1 m (Temporary Immersion (up to 1 m)). IP47 provides 6 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP47 offers higher overall protection than IP21. Choose IP47 for harsher environments; IP21 may suffice for milder conditions and can be more cost-effective.