Forklifts are the workhorses of the industrial world, operating in environments that test every component to its limit. Among these, relays play a crucial role in ensuring operational reliability, safety and efficiency. 

Yet as forklift technologies evolve, especially with the rise of electrification, off-the-shelf solutions can sometimes struggle to keep up. In many cases, the answer lies in custom relay design.

The critical role of relays

Relays regulate the flow of electrical current across key systems in forklifts, powering everything from drive motors and hydraulic lifts to emergency stop systems and reverse alarms. They also optimise auxiliary components like lighting and HVAC systems where energy efficiency directly impacts battery life, especially in multi-shift operations.

Modern forklifts increasingly rely on lithium-ion battery systems operating at 48–96V. These higher voltages can cause arcing and premature failure in standard off-the-shelf relays originally designed for 12V or 24V systems. 

When incorrectly matched, such relays may weld shut or degrade at triple the expected rate, driving up maintenance costs and safety risks.

Environmental pressures on relay components

Forklift relays must withstand significant mechanical and environmental stress. Vibration, often in the range of 5 to 20Gs, can loosen connections, deform terminals and lead to micro-movements that accelerate contact wear. 

Temperature fluctuations also present challenges: relays are exposed to both external heat from engines and internal heat from switching activity, which can weaken materials and lead to contact welding over time.

Contaminants such as dust, moisture and even biological elements like insects can infiltrate open-frame relays, especially in applications like grain silos or refrigerated storage. 

When combined, these factors can degrade relay performance and significantly reduce lifespan.

The case for customisation but not exclusively

While custom relays offer engineering enhancements designed to handle these stresses, off-the-shelf (OTS) relays still have their place, particularly in auxiliary systems where voltage and environmental demands are modest. 

OTS solutions remain a practical and cost-effective choice for standard lighting, controls or dashboard electronics.

However, specialised forklift systems benefit significantly from customisation, particularly those operating at higher voltages or in rugged environments.

Custom relays can include:

- Gas-sealed chambers to prevent arcing
- Modified housing and terminal designs for tight or legacy configurations
- High-temperature and flame-retardant materials
- Arc suppression and magnetic blowout features for inductive loads
- These adaptations are essential in applications where performance, longevity and safety are non-negotiable.

The optimal solution often blends both approaches: using standard relays where appropriate and custom designs where it’s critical.

Adapting to the demands of modern forklifts

As forklifts evolve in response to electrification, automation and durability demands, relay design must evolve in parallel. 

With a shift to electric, there is a need to manage higher voltage DC loads and the associated electromagnetic interference (EMI). 

Meanwhile, the market for autonomous guided vehicles (AGVs) is rising. This pushes manufacturers to deliver high-performance relay systems in smaller, lighter formats.

Durability remains a central concern. Modern relay solutions must be engineered for longevity whether with shock, vibration or environmental contaminants. 

Customisation enables this resilience, but it must be supported by close collaboration between manufacturers, OEMs and operators to ensure fit-for-purpose design.

There is no universal answer. Instead, the most effective strategies recognise when to rely on the tried-and-tested simplicity of standard components and when to break the mould with a tailored solution that meets the evolving demands of today's forklift systems.