4 Tips to Help Students Understand Load Charts

A load chart indicates the crane’s capabilities and how its lifting capacity varies when considering radius, boom angle, and boom length. The loads weight, deductions, boom length, boom angle, parts of line, and other factors will vary the capacity. Load charts are one of the most important resources for crane operators, and understanding them is paramount.  

Crane Industry Services trainers have noticed that when students take assessments for certification testing, the load chart portion is where students are most likely to make mistakes. Tips to help understand load charts are:  

1. Read the questions slowly and carefully. See what information is given, and what the question is asking. If the question is asking for gross capacity, the gross capacity is stated in the capacity listing portion of the chart. Simply locate the number based on the criteria given.  No math is required to know the gross capacity!  Net capacity, on the other hand, is the gross minus applicable deductions. 

2. Locate the correct chart! For example, some load charts will have different charts for outriggers fully extended, outriggers mid extended, with a certain amount of counterweight, and on rubber. For example, if the question asks for gross capacity at a certain boom and radius length, lifting with outriggers fully extended, then use the outriggers fully extended chart. 

3. Read the notes. Always read the notes in the charts.  If you don’t, you may miss important information that is needed when calculating net capacities. 

4. Manufacturer’s load charts look different because they are specific to the make, model, and configuration of the crane. However, they all include the same type of necessary information for interpretation. Only use the load chart that is found in the operation manual or posted by the manufacturer for that machine. Verify that you have the correct load chart by matching the serial number on chart with the serial number on the machine.