Most load cell applications have size restraints in regards to the size of the load cell that can be used. Miniature load cells are generally recommended when the smallest size and weight of the sensor is required. We have seen many customers mistakenly inquire about a miniature load cell, over a more capable sensor, for an application that a miniature load cell is not necessary. In other words, their application could have used a more accurate but physically larger load cell, instead, they chose the miniature or subminiature design that would not be the best choice.
These miniature sensors are best for applications when the accuracy requirements for the scale or test are not that critical. Many applications do not require a high degree of accuracy this is what a miniature load cell is designed for.
In some cases, miniature load cells are more expensive than their larger counterparts. The difference in cost is typical because a mini-load cell can be more difficult to manufacture than standard-sized load cells. Although slightly more costly at times, miniature load cells are worth it when they fulfil your needs.
There is a miniature version of most types of load cells such as S-type, canister, button, and thru-hole designs. The previously noted downfall to miniaturizing a sensor is that you give up accuracy, the obvious advantage is the size (it will fit where a standard load cell will not). There are multiple types of load cells within the mini category including, micro, subminiature, and miniature. Typically the smaller they are, the more the accuracy is reduced and the cost is increased. On average a miniature load cell will have a non-repeatability specification of 0.2 to 1% of the full-scale capacity. This range of error is 2-10x more than if using a standard size load cell.
For portable applications, a miniature load cell can be desirable, especially for larger capacity sensors. The convenience factor of a miniature load cell is a big advantage, they are easy to handle and can easily fit in a case along with the load cell display for on-the-go jobs. Being able to easily secure these instruments and sensors can reduce the chance of damaging them during transport.
Some manufacturers specialize in standard load cells and other miniature load cells. Even though either size is still strain gage based sensors, it is uncommon that a manufacturer is good at building both. They typically choose one or the other as their main product line and carry a few of the other to give the customer options.
Industrial load cell suppliers need to carry both types because one size does not fill all. These suppliers should have well-educated sales technicians to help inform the customer if a standard or miniature load cell would be the right choice for their application.
Miniature Load Cell Conclusion
When the application requires a miniature load cell then the decision is obvious. If you have room for a larger form factor and accuracy is critical, consider using a standard industrial-sized load cell.