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Load Cells for Food and Beverage Washdown: IP Ratings, Stainless Steel and Hygiene
In a food, beverage or dairy plant, load cells get hosed down with hot water and strong cleaning chemicals every day, so they must be sealed, made from corrosion-resistant stainless steel and designed so dirt cannot collect on them. The key things to look for are a high ingress protection rating (IP66 or better, and IP69K for hot high-pressure washdown), a welded or hermetically sealed body, 304 or 316 stainless steel, and a smooth, crevice-free shape. This guide explains these terms in plain language, shows how to match a cell to your cleaning method, and gives examples from our range. It is general information, so always check your own hygiene and food safety requirements.
What makes a washdown environment tough?
A packing room or dairy is hard on electronics for several reasons.
- Water: floors, walls and equipment are sprayed down, often daily.
- Heat: hot water or steam is used to dissolve fat and sugar.
- Pressure: high-pressure hoses force water into small gaps.
- Chemicals: caustic, acid and sanitising agents are used in cleaning, and some are corrosive.
- Salt and moisture: in seafood and meat plants, brine attacks ordinary metals.
- Hygiene rules: surfaces must be easy to clean, and bacteria must have nowhere to hide.
A cheap aluminium load cell with a lightly coated body will corrode, leak and drift in these conditions. Moisture getting into the cell or cable is the number one cause of failures. For why, see load cell troubleshooting.
IP ratings explained simply
IP stands for ingress protection. The first digit is about dust (6 is the highest), and the second is about water. The table summarises the ratings you will see on load cell datasheets.
| Rating | Plain English | Suits |
|---|---|---|
| IP65 | Dust-tight and protected against water jets | Light washdown and splashing |
| IP66 | Dust-tight and protected against powerful water jets | Regular hose-down |
| IP67 | Dust-tight and can survive temporary immersion | Wet areas, occasional flooding |
| IP68 | Dust-tight and can survive continuous immersion under conditions set by the maker | Very wet or submerged duty |
| IP69K | Protected against close-range, high-temperature, high-pressure spray | Hot, high-pressure washdown |
The IP69K test uses very hot water at roughly 80 degrees Celsius sprayed at high pressure from close range, so a cell with this rating is built for the harshest cleaning. Remember that the rating applies to the cell body and its cable entry, so check the connectors, junction boxes and cables as well. A chain is only as strong as its weakest link.
Sealing methods: potted or hermetic?
Potted cells
The strain gauges are covered in a protective compound, with additional mechanical covers. This is a good, economical solution for many applications. Revere, for example, uses a proprietary potting compound plus mechanical protection in cells like the 5123 and 9363.
Hermetically sealed (welded) cells
The sensing area is sealed inside a welded stainless steel body, usually with a glass-to-metal cable entry. Nothing can get in, even over many years of washdown. These cost more but are the best choice for the toughest conditions. The Tedea-Huntleigh Model 355 is an IP68 hermetically sealed bending beam, and the Revere ASC2 is a fully welded compression cell with IP66, IP68 and IP69K ratings.
Stainless steel grades
- 304 stainless steel: a good general food-grade metal that resists most cleaning chemicals and water.
- 316 stainless steel: contains molybdenum, which improves resistance to salt, chlorides and some acids. It is the safer choice for seafood, brines, pickling and chlorine-based cleaners.
- Coated steel: cheaper, but a scratch can start corrosion. Best in drier areas.
- Aluminium: light and economical for dry bench scales, not for wet or chemical duty.
For a full comparison, read load cell materials.
Hygienic design: shape matters
Even a stainless cell can be a problem if it has cracks and grooves where food residue collects. Look for:
- Smooth, rounded surfaces with no deep pockets.
- Few crevices, with welded joints rather than gaps.
- Mounting hardware that drains water and does not trap it.
- Cable entries that are fully sealed and positioned so water runs away.
- Low-profile designs that leave less space under the scale for dirt.
The Revere RLC ring torsion cell is a low-profile stainless steel cell with IP66, IP68 and IP69K ratings, designed for food, chemical and allied process industries.
Matching the cell to the job
| Application | What to look for | Example |
|---|---|---|
| Dairy or beverage tank | Stainless, sealed, tolerant of side load | Shear beam cells such as the 65016-W (IP67) |
| Floor scale in a wash area | Stainless single-ended beam, IP67 or IP68 | Sealed beam cells; ask us about stainless options |
| Check weigher or filler | Fast response, IP66 washdown, damping | Model 240 (IP66, stainless steel version available) |
| Multi-head weigher | Self-contained, shock tolerant | Model 9010 (IP65) |
| Hopper or bin on a frame | Low profile, sealed | Revere RLC (IP69K) |
| Hanging bin or conveyor hopper | Stainless S-type | 60063 (IP68) |
Real-world example: a juice bottling line
A small juice maker fills bottles on a rotary filler. The line is washed with hot water and a chlorine-based sanitiser at the end of every shift.
- Problem: their old cells, aluminium with a painted finish, started giving unstable readings after six months because water crept into the cable entries.
- Diagnosis: the IP rating was too low for the washdown, and the cable entries were not sealed against jets.
- Solution: they switched to sealed stainless steel cells with IP66 or higher protection, selected a model designed for fast filling, and used sealed cable glands and washdown-rated junction boxes. See load cells in batching and filling systems.
- Result: stable readings through repeated washdowns, and fewer breakdowns.
Cable, glands and junction boxes
- Choose cable with a jacket that resists the cleaning chemicals and temperature.
- Use sealed cable glands, installed correctly with the right torque.
- Point cable loops downward so water drips away, and avoid letting water pool in the cable path.
- Choose junction boxes with a high IP rating, stainless or plastic as suits the cleaning process.
- Do not rely on sealant tape or silicone to fix an unsuitable cable entry.
Cleaning and care
- Follow the maker’s guidance on which cleaning agents and temperatures are acceptable.
- Rinse off chemicals after use so they do not sit on the cell.
- Do not aim high-pressure jets directly at cable entries more than necessary.
- Inspect cells and cables regularly for corrosion, cracks and damage.
- Re-check calibration after any damage or major cleaning change. See load cell calibration.
Food safety and compliance
A load cell is usually not in direct contact with food, but it is part of the equipment in a food area, and your hygiene plan will cover it. If you must meet specific standards, such as those set by your customers or an auditor, ask for the necessary material and surface information from your supplier. Where products are sold by weight, see legal for trade weighing in Australia.
Chemicals and stainless steel: what to watch
Stainless steel resists corrosion because of a thin invisible film on its surface. Some cleaning chemicals attack that film. Chlorine-based sanitisers and salty brines can cause tiny pits in 304 stainless steel, especially if they are left to dry on the surface. Strong acids can also cause damage. Using 316 stainless steel, rinsing thoroughly after sanitising and not letting chemicals sit on the cell are simple ways to extend its life. Never clean stainless steel with steel wool or steel brushes, which leave iron particles that rust.
Drainage, slope and mounting
Water that stays on a cell or its mounting plate invites corrosion and bacteria. Where possible, mount cells so that water can run off, avoid flat ledges that collect liquid, and leave enough space underneath for cleaning. Mounting hardware should also be stainless steel and the same grade as the cell, because mixing metals can cause galvanic corrosion. Check that bolts and washers do not create crevices around the cell. See load cell installation for mounting methods by type.
A quick buying checklist
Before you order, confirm the IP rating of the cell and the cable entry, the stainless steel grade, the cleaning chemicals and temperatures used on site, the capacity and number of cells, and whether the mounting hardware is also stainless steel. Ask for the datasheet and keep it with your maintenance records, so the next technician knows exactly what is installed.
Frequently asked questions
Is IP67 enough for washdown?
IP67 protects against temporary immersion but is not a guarantee against hot, high-pressure jets. For regular hot washdown, IP66 plus a sealed design or IP69K is safer.
What is the difference between IP68 and IP69K?
IP68 is about continuous immersion. IP69K is about close-range, hot, high-pressure spray. A cell can have both, as the ASC2 and RLC do.
Do I need 316 stainless steel?
If salt, chlorides or strong acids are present, yes. For general food areas, 304 is often sufficient.
Can I use a coated steel cell in a wet area?
It can work in occasional splashes but not in daily heavy washdown, because scratches expose the steel.
How do I choose?
Send us details of your cleaning method, temperature, chemicals and capacity via the contact page, and read our complete load cell guide for the basics.
Explore our stainless and sealed load cells
Browse the canister load cells, damped load cells and tension and compression disks, or see the whole shop.
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