Height limiters: Everything you need to know


What is a height limiter?

Height limiters are fitted to excavators to monitor the machine’s position in relation to pre-set height limits, warning operators when these are approached and improving worksite safety. This helps prevent collisions with overhead hazards such as bridges, signs and power lines, protecting operators and critical infrastructure from the risks of construction. To maximise safety, select systems such as the PME range will also restrict movement if limits are reached.


Why do I need a height limiter?

You need a height limiter to protect excavators, operators and assets from overhead hazards. From civils to rail, major construction sites increasingly require excavators to be fitted with an approved system. Using a height limiter demonstrates a standard of safety across your operations, opening the door to high-profile projects.  

Height limiters can also secure your profits. Overhead collisions damage excavators, resulting in costly repairs and increased downtime. These also disrupt key rail and road networks, potentially incurring fines and reputational damage. Equipping excavators with a height limiter future proofs your operations, protecting your profits against unexpected incidents while helping to grant access to new opportunities.

For added safety, certain height limiters offer envelope control. This allows operators to set minimum and maximum radius limits, safeguarding their cab from the excavator’s boom and dipper. 


 What can I install it on?

Height limiters are designed to protect single, mono and triple boom excavators. There are also options available for backhoes and telehandlers.



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Maximising accuracy

While all height limiters monitor the excavator’s boom, many do not account for the dipper. More advanced systems display the highest point of both the boom and the dipper in real time, maximising height limiting accuracy for enhanced site safety.

Motion cuts

While all height limiters use alarms to warn operators when pre-set restrictions are approached, some systems feature motion cuts that automatically restrict machine movement when these limits are reached. We always recommend using systems with motion cuts, as this protects against user error while allowing operators to focus on the job at hand.

As part of our aim to ensure that all operators return home safely from work, our PME range features motion cuts as standard.

Full-envelope control

Limiting machine height, reach, slew and depth, full-envelope control leaves nothing to chance by helping to mitigate all surrounding fixed hazards. Full-envelope control is critical if you want to work safely inside tunnels, alongside traffic, underneath live power lines, or within any other confined urban space.

Enabling operators to set minimum radius limits, full-envelope control also protects the excavator cab from boom movements. This is particularly important for ensuring the safe operation of excavators using specialist attachments that could strike the cab in certain operations, as well as for those with multiple articulations.

As operators need all the space they can get, our full-envelope solutions use virtual wall technology to expand the safe working zones of machines when compared with other systems. Ideal for working next to highways or railways, operators can easily set singular, or dual-wall with the added option of multi-point exclusion zones to avoid multiple hazards in busy environments, improving productivity by minimising set-up time.  

Complying with regulations

Using a height limiter is mandated in various construction sites to ensure safe excavator operation.

Civil construction sites increasingly require excavators to be fitted with a height limiting system, especially in highways applications and other major infrastructure projects. More so than ever, site managers are keen to ensure that these systems comply with the appropriate health and safety standards. Rigorously tested in JF Prolec’s UK production facility, our PME technology complies with the latest regulations to maximise safety.  

For rail operations, there are stringent regulations in the UK and EU to ensure that safety comes above all else. These require road-rail (hi-rail) excavators to be equipped with an approved height limiter that features full-envelope controlas well as mandating compliance with a range of safety standards. Both PME Rail and Euro Rail are fully compliant with UKRIS1530 and Europe’s EN15746 standards to deliver reliable protection for rail operatives and the passing public.



Safe system use

It’s important that height limiters are used correctly to ensure safe excavator use across your operations. That’s why our PME range features a simple, icon-led display to allow operators to set limits easily and accurately. Read our PME Quick Start Guide to learn more.

Even so, training your operators to use height limiters effectively is always recommended to maximise safety and productivity.

Override key switch

There are times where height limiting systems need to be overridden to react to exceptional circumstances. In these situations, you can rest assured that all of our PME systems with motion cuts come with override key switches as standard.

Managing access to limits

As some sites are more hazardous than others, supervisors sometimes need to set safe working zones themselves. With our PME technology, supervisors and site managers can easily set and manage access to limits directly from the device.

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