Safe Load Indicator Installation Guide: New and Existing Cranes

A safe load indicator (SLI) is one of the most important safety devices on a crane. It watches the load. It warns the operator before things get unsafe. In India, BIS standards and the Factories Act, 1948 treat an SLI as a basic safety need on most sites.

But how does the install work? It depends on your crane. A new crane can have an SLI built in at the factory. An older crane needs a retrofit instead. A retrofit means the system is added later, after the crane is already in use. This guide walks through both paths, the Klug Avalon way.

What Installation Involves, at a High Level

Here is a quick recap first. An SLI checks three things in real time: the load, the boom angle, and the working radius. The boom is the long arm of the crane. The radius is how far out the crane reaches. The SLI checks these readings against your crane’s rated capacity. That number comes from your crane’s load chart. The chart is supplied by the crane maker.

If the load gets close to the limit, the SLI warns the operator. Some systems can even stop the crane from lifting further. Want the full picture? Read our guide on what is a safe load indicator?.

This guide covers two paths:

• Fitting an SLI on a brand-new crane, during the build.
• Retrofitting an SLI onto a crane that is already on site and working.

The end goal is the same either way. You get a system that reads your crane’s real load, angle, and radius, and checks it against the load chart. You may also hear this called an LMI or an RCI. These terms are often used for the same kind of system. Our SLI vs. LMI vs. RCI guide explains the small differences, if you want to dig deeper.

Installation Process on New Cranes (Klug’s Approach)

People often ask us one thing: what does Klug Avalon’s own install process look like? Here are the steps we follow.

1. Crane assessment and load-chart mapping. First, we look at your crane type. We also study the load chart from your crane’s maker. This chart sets the rated capacity. Our SLI is checked against this number.
2. Sensor placement. Next, we fit sensors for the load, the boom angle, the boom length, and the slew or radius. Where each sensor goes depends on your crane type. This could be a mobile crane, a tower crane, an EOT crane, or a crawler crane.
3. Cabling and display fitting. We run the cabling through the crane. Then we fit the control unit and display inside the operator’s cabin. It sits where it is easy to see and use.
4. Calibration. Calibration means setting the system so its readings are correct. We do this twice: once with an empty boom, and once with a loaded boom. This makes sure the readings match real working conditions.
5. Function testing. We test every warning the system can give. This includes overload alerts, anti-two-block warnings (a warning for the hook getting too close to the boom tip), and, on some models, an automatic motion cut-off.
6. Documentation and handover. You get full paperwork and compliance records. These are ready for BIS or Factories Act inspections at any time.
7. Operator training. Before we leave the site, your operator gets a full walkthrough. They learn how to read the display. They also learn how to act on each alert.

A few things set Klug Avalon’s process apart. Every system is tested in our own in-house quality lab before it ever reaches your site. Every unit is also built to match your crane’s own load chart, not a generic one. With more than 30,000 systems installed worldwide, we have fine-tuned this process across almost every crane type in use today.

Installation for Existing Cranes (Retrofitting)

Most cranes working on Indian sites today are not brand new. That is exactly why retrofitting matters so much.

• Is your crane ready for a retrofit? Most cranes can take one. They just need enough electrical capacity and solid mounting points for the sensors. We check this before any work begins.
• How retrofitting is different. On a new crane, we build everything around a clean setup. On a retrofit, we work around the crane’s existing wiring and controls instead. We also fit sensors to an older boom or jib. Sometimes the original load chart is missing or out of date. When that happens, we rebuild the data from the crane’s real measurements.
• Timeline and downtime. Every retrofit timeline depends on the crane type and the site conditions. We plan the work carefully. This keeps your crane off the job for as little time as possible.
• Crane types we retrofit. We commonly retrofit mobile and hydraulic cranes, tower cranes, EOT cranes, and crawler cranes across India.
• When retrofitting is not the right fit. In rare cases, a crane’s age or condition means a retrofit just is not practical. If that is true for your crane, we will tell you straight away. Then we will talk through what makes sense instead.

New Installation vs. Retrofit: Which Applies to You

Not sure which path fits your crane? This table gives a quick side-by-side view.

	New Crane Installation	Retrofit on Existing Crane
When it happens	During the crane build, or soon after	At any point in the crane’s working life
Load chart	Supplied fresh by the crane maker	May need to be rebuilt from the crane’s specs
Site downtime	Minimal, planned in with delivery	Scheduled around your project timeline
Main goal	Build safety in from day one	Bring an older crane up to today’s safety standard

Not sure which path fits your crane, a new install or a retrofit? Speak to our team and we will help you work it out.

Frequently Asked Questions