IPX1 & IPX2 Dripping Water Testing
Validating protection against condensation, vertical leaks, and falling droplets.
Not Every Product Needs to Survive a Fire Hose
For many indoor devices, the threat isn’t a high-pressure jet or submersion—it’s a leaky ceiling pipe, a spilled cup of coffee on a desk, or heavy condensation dripping from an HVAC vent above.
IPX1 and IPX2 are the specific ratings defined by IEC 60529 to address these vertical ingress risks. They are standard requirements for:
- Medical Equipment: Bedside monitors and IV pumps.
- Office Electronics: Servers and desktop appliances.
- Indoor Lighting: High-bay fixtures subject to roof leaks.
At Castle Compliance, we test these products using a specialized Drip Box system that creates a uniform field of falling water droplets, ensuring your ventilation designs don’t inadvertently funnel water onto sensitive components.
The “Drip Box” Methodology
Unlike spray tests that use solid stream nozzles, IPX1 and IPX2 use a large tank with a perforated bottom (the Drip Box). Water dispenses through hundreds of tiny needle-like nozzles spaced in a square, 20 mm x 20 mm array by means of water head pressure. Since the flow rate is relatively slow, droplets form on the ends of each nozzle until their weight causes them to fall. This creates a uniform field of falling water droplets. We regulate the water flow to create a precise “rainfall” effect. The flow rate is 1 mm/min for IPX1 and 3 mm/min for IPX2.
The entire upper surface of the device under test (DUT) is exposed to the field of dripping water. When the base of the drip box is smaller than that of the DUT, the latter may be divided into several sections with each section being large enough to be covered by the dripping water. The test is continued until the whole area of the DUT has been sprinkled for the specified time.
IPX1: Vertically Dripping Water
This rating simulates water falling straight down on a device sitting in its normal operating position.
- Test Condition: The product is placed on a turntable rotating at 1 r/min.
- The “Eccentricity” Rule: The device is not centered. It is placed with an eccentricity (offset) of approximately 100mm from the axis of rotation. This ensures the product moves through different drip paths rather than spinning statically under the same holes.
- Flow Rate: 1 mm per minute (+0.5 mm/min tolerance).
- Duration: 10 minutes.
IPX2: Dripping Water (15° Tilt)
This rating is significantly harder than IPX1. It simulates a device that is slightly uneven or water falling at a slight angle.
- Test Condition: The product is tested in 4 fixed positions. For each position, the enclosure is tilted 15 degrees from the vertical in two mutually perpendicular planes.
- Flow Rate: 3 mm per minute (3x the volume of IPX1).
- Duration: 2.5 minutes per position (10 minutes total).
- The Challenge: The tilt allows water to run under overlapping lips or louvers that would normally block vertical rain.
IPX1 vs. IPX2: Quick Comparison
| Feature | IPX1 | IPX2 |
| Motion | Dynamic (Spinning Turntable) | Static (Fixed Tilt) |
| Offset | 100mm Eccentricity | None (Fixed) |
| Product Angle | Vertical (Normal Use) | Tilted 15° |
| Water Volume | 1 mm/min | 3 mm/min |
| Primary Threat | Vertical Leaks / Condensation | Tilted installation / Angled Drips |
Engineering Note: Passing IPX1 does not guarantee passing IPX2. The 15° tilt often exposes side vents that are protected when the unit is flat.
Common Failure Modes
Even though these are “low” ratings, products fail them frequently due to simple design oversights.
1. The “Pooling” Problem
Flat-topped enclosures often allow water to pool. If screw holes or seams are located in these depressions, the standing water will eventually seep through via gravity or capillary action.
- Castle Tip: Avoid holes and fasteners on the top of enclosures. Design a slight crown or slope on the top surface to encourage runoff.
2. Louver Orientation (IPX2 Failures)
Ventilation louvers designed to block vertical rain often fail when the unit is tilted 15 degrees. The tilt changes the angle of attack, allowing droplets to bypass the slat and hit the PCB inside.
- Castle Tip: Use a “labyrinth” or Z-shaped louver design rather than simple angled slats.
3. Drainage Paths
If water gets in (which is often allowed), it must get out. A common failure is water entering a non-critical area but getting trapped, eventually filling up until it reaches a live connector.
- Castle Tip: Ensure your bottom housing has drain holes located at the lowest point.
Acceptance Criteria: Does Water = Fail?
Not necessarily. IEC 60529 states that water ingress is allowed as long as it does not:
- Interfere with correct operation.
- Reach live parts (shock hazard).
- Accumulate near cable ends.
The Castle Compliance Approach:
We don’t just look for water; we look for danger. After the test, we open your unit and document exactly where the water went. If drops entered but stayed safely on the plastic floor away from the electronics, we can often issue a passing report based on your defined acceptance criteria.
Ensure Your Indoor Equipment is Protected
Don’t let a simple drip cause a short circuit. Contact our engineering team to schedule your IPX1 or IPX2 test.