What Are the Different Types of Crane Scales?

Crane scales can be broken down into four major types: digital industrial scales, heavy-duty foundry scales, tension dynamometers, and wireless scales. And while there are differences between these types, they all share the same basic design and functionality—they use a load cell to measure weight or force, ensuring safety in overhead lifting and other industrial applications. Different types of crane scales can be found in warehouses and foundries, used for proof load testing, as well as in event and entertainment rigging.

Key comparisons: crane scale types and specifications

Digital industrial crane scales

A digital industrial crane scale is the industry standard measuring device for the accurate weighing of suspended loads. They play a vital role in industrial lifting safety and other lifting and weighing applications across industries.

The basic design features a central load cell body equipped with a strain gauge, which converts mechanical force into a precise electrical signal. This signal is then processed into a readable measurement, such as kilograms or pounds. A hook is attached to the lower side of the load cell body, which allows operators to easily and safely attach the load to be lifted. On the upper side of the load cell, a shackle is usually attached for connecting the scale to the crane’s hook or other overhead weighing equipment.

Digital industrial crane scales are valued for their accuracy and portability. Their LED or LCD screens make measurements clearly visible, even from a distance or in challenging lighting conditions. Most crane scales also feature tare, zero, and other basic functionalities, making them ideal for a range of applications and industries from manufacturing to shipping docks and more.

Heavy-duty foundry crane scales

While basic crane scales are great for standard industrial applications, some environments call for a scale with more advanced features. For high-heat applications, you’ll need a foundry crane scale that can withstand harsh conditions and extreme heat without suffering damage.

Heavy-duty foundry crane scales are equipped with a special metal heat shield and thermal fabric jacket to protect the sensitive electronics. They work by delaying the rise in temperature, allowing operators to weigh molten materials at temperatures exceeding 1,000°C before the scale's internal temperature becomes too high.

Tension dynamometers (shackle scales)

While traditional crane scales that feature an upper shackle and lower hook can be used in a variety of applications, they are limited in their maximum capacity. That’s where a tension dynamometer comes in. These are basically just like a normal crane scale, but utilize both upper and lower shackles instead of a lower hook. So while they’re technically considered a dynamometer rather than a crane scale, they function the same. 

The tension dynamometer is useful in two ways when compared to other crane scales:

1. They can be used in vertical tension applications, such as measuring tension in cables, wires, or guy lines.
2. They’re available in much higher capacities, ranging up to 250 tons. 

So if your application calls for loads or forces exceeding around 32 tons, this is the type of weighing system you’ll need.

Wireless and Bluetooth crane scales

Wireless crane scales, which use either RF or Bluetooth technology, are the most advanced options in the market. As opposed to weighing systems with a wire or cable, wireless crane scales transmit the weight data wirelessly to a handheld indicator, remote receiver, or even to tablets and smartphones. This allows operators to remain at a safe distance from the lifted load, and eliminates the tripping hazard from wired systems. This makes them the safe choice in hazardous work environments. 

Frequently asked questions

Q: What’s the difference between a crane scale and a dynamometer?

A: The primary difference is that crane scales have a lower hook and upper shackle, while dynamometers have both upper and lower shackles. This means the crane scales are largely limited to vertical lifting operations, while dynamometers can be used during horizontal force measurement.

Because of the hook, crane scales are also limited in their size and therefore in their maximum capacity as well, with dynamometers being capable of much higher capacities.

Q: Do I need an NTEP-certified crane scale?

A: NTEP certification is necessary when using a scale for determining the price or quantity of a good being sold, for example in retail or food service. For most industrial lifting applications of the sort where a crane scale would be used, NTEP certification isn’t relevant.

Summary: choosing the right overhead scale

Choosing the right overhead crane scale depends greatly on the nature of the applications you’ll use it for. For instance, capacity requirements, environmental conditions, and accuracy needs can vary widely between a warehouse weighing palletized goods and a foundry handling molten metals. 

Crane scale selection checklist: 7 steps to the right choice

Here’s a practical approach to help you find the weighing system that’s right for you.

1. Determine your maximum lifting capacity
   Consider all possible applications and find the heaviest object you might lift. Then, give yourself a buffer of as much as 20% above this heaviest weight to find the right capacity. Also, make sure the crane scale has at least a 5:1 safety factor.
   
   
2. Available headroom
   If you’ll be working indoors, consider your worksite and whether headroom is a factor. If you need a compact weighing system, you may be better off with a dynamometer than a crane scale with a large hook.
   
   
3. Operating environment
   It’s crucial to consider the environment in which your overhead weighing operations will be conducted, and to select the appropriate optional add-ons and features for it. For example, you may need higher environmental protection, such as IP 68 for marine projects. Or, for high-heat applications, a foundry scale with a heat shield is necessary.
   
   
4. Regulatory compliance
   If your application calls for selling goods by weight, you’ll need an NTEP-certified (Legal for Trade) scale. If you’re only using it for internal inventory or other industrial lifting applications, then an NTEP-cert isn’t necessary.
   
   
5. Visibility of readings
   Consider how far the operators will be from the load during the operations, and if multiple operators need to see the reading. This will determine both the size and number of readouts needed. Further, consider if a wireless system with one or more remote handheld indicators is right for you.
   
   
6. Power source & battery life
   This can be more than just a matter of convenience. For example, if the scale will be part of a fixed installation for load monitoring, then long battery life is a must. Eilon Engineering wireless systems feature 2,000 to 5,000 hours of continuous battery life for “always on” monitoring.
   
   
7. Data logging & system integration
   If your lifting and weighing operations entail record keeping, you’ll need some sort of data logging capability. For example, Eilon handheld indicators with datalogging are capable of storing lift data, which can then be transferred to a PC for record keeping and analysis.