Choosing a load cell for a batching plant comes down to matching the cell to what it has to weigh aggregate, cement, water or admixture and to the way that vessel is supported. Get the capacity, cell type, mounting and environmental rating right and your weigh hoppers stay accurate batch after batch; get them wrong and you face drift, non-repeatable batches and premature failures in a dusty, wet, vibrating environment. This guide walks through the specifications that matter and how they map to the load cells and weighing parts we stock.
It is written for plant engineers, maintenance teams and buyers specifying a replacement or upgrade. If you already know the exact part you need, you can jump straight to our load cell range.
Start with the weighing point on your plant
A concrete batching plant rarely uses one type of load cell everywhere. Each weighing point has its own load, geometry and environment, so begin by identifying where the cell will sit:
- Aggregate weigh hopper / weigh frame the heaviest live load on the plant, usually carried on three or four support points.
- Cement weigh hopper a suspended or supported vessel dosing cement by weight; abrasive dust is the main enemy. See our cement weigh hopper parts.
- Water and admixture vessels smaller capacities, often suspended, frequently in tension.
How the vessel is carried decides whether the cell works in compression (the vessel sits on top of it) or tension (the vessel hangs from it). That single distinction drives most of the selection that follows.
Key specifications to get right
Capacity and the number of cells
Size on the total gross weight at that point the empty vessel (dead load) plus the maximum material it will ever hold (live load) then divide by the number of support cells. Add margin so the working load sits at roughly 60–80% of the cell's rated capacity; the remaining headroom absorbs shock loading, off-centre loads and vibration from the plant. Under-sizing invites overload damage, while grossly over-sizing throws away resolution and makes small water or admixture doses hard to read.
Tip: most batching hoppers are carried on three or four cells. Three points are inherently stable (no packing needed); four are common on rectangular frames but may need a corner trimmed. Buy all cells at the same capacity so they share the load evenly.
Cell type and mounting
Match the cell to how the vessel is supported:
| Cell type | Works in | Typical batching use |
|---|---|---|
| Compression (column / rocker) | Compression | Large aggregate hoppers and frames sitting on mounts |
| Shear / bending beam | Compression | Mid-capacity supported hoppers and tanks |
| S-type | Tension | Suspended cement, water and admixture vessels |
| Single point | Compression | Small platform or low-capacity weighing |
Whatever the type, use proper mounting hardware. Weigh modules, rocker assemblies and load cell mounting accessories keep the load axial, let the vessel expand and contract with temperature, and take the side thrust that vibration and material flow generate the single biggest cause of non-repeatable weighing on a batching plant.
Environmental protection and material
Batching plants are wet, dusty and often washed down. Specify at least IP67 for cell and cable gland; choose IP68 or IP69K where cells are submerged, pooled or pressure-washed. In an aggressive cement or coastal environment, stainless steel cells outlast nickel-plated alloy steel. Where the plant has a classified dust-explosion zone, you will need ATEX-rated cells and junction boxes.
Output and system compatibility
Load cells are ratiometric: they return a small signal in mV/V (2 mV/V is the common batching value) proportional to the excitation and the applied load. When you run several cells into one weighing point they must share the same rated output and capacity so they sum correctly through the load cell junction box. That summed signal then feeds a weigh controller or a load cell indicator for calibration, batching set-points and output to the PLC. For trade or tight QA weighing, choose a certified accuracy class such as OIML C3.
Compression vs S-type when to pick which
If the vessel sits on its supports, use a compression cell (column, rocker or shear beam) with a weigh module that keeps the load vertical. If the vessel hangs from a frame typical of cement, water and admixture pots an S-type load cell working in tension is the natural choice, secured with rod-end bearings so it stays aligned as the vessel swings and settles. Don't force one type into the other geometry; the mounting, not just the cell, determines accuracy.
What else you'll need
A load cell is one part of a weighing point. Budget for the supporting parts at the same time:
- A junction box (equalised, or ATEX where required) to sum and trim the cells.
- A weight indicator or batch controller for calibration and set-points.
- Mounting hardware, rod-ends and cable from load cell accessories.
Frequently asked questions
How many load cells does a batching plant weigh hopper need?
Most hoppers use three or four cells. Three support points are self-levelling and need no packing; four suit rectangular frames but may require a corner to be trimmed. Fit all cells at the same capacity so the load shares evenly.
What capacity load cell do I need?
Add the empty vessel weight (dead load) to the maximum material it will hold (live load) to get the total gross weight, divide by the number of cells, then size so the working load is about 60–80% of each cell's rated capacity. That headroom absorbs shock, off-centre loading and plant vibration.
Should I use a compression or S-type load cell?
It depends on how the vessel is carried. Vessels that sit on their supports use compression or shear-beam cells; vessels suspended from above use S-type cells working in tension. The mounting geometry, not the material being weighed, decides the type.
What IP rating do I need for cement dust and washdown?
Specify IP67 as a minimum for a batching plant. Choose IP68 or IP69K where cells are submerged, sit in pooled water or are pressure-washed, and consider stainless steel construction in aggressive cement or coastal conditions. Use ATEX-rated cells in classified dust-explosion zones.
Can I replace one load cell or must I change them all?
You can replace a single cell if its capacity and rated output match the others exactly. If the output differs, you will need a trimming (equalised) junction box or a full recalibration, so it is often cleaner to replace a matched set on older installations.
Browse the range
Ready to specify? Browse our batching plant load cells → including S-type cells from Thames Side and Applied Weighing, plus junction boxes, indicators and mounting accessories to complete the weighing point. Not sure which fits your hopper? Contact our team with your capacity and mounting details.