Project managers and technical staff often have to deal with temporary installations, such as at construction sites, events or test rigs. These installations present unique challenges when it comes to power distribution, peak consumption and cabling. Overloading is a common risk that leads to dangerous situations, failures and costly downtime. In this article, you will learn what exactly overloading is, how to prevent it, and what concerns there are when designing and managing temporary electrical installations.
Why overwork is a serious risk
Temporary installations are usually not designed for long-term or maximum use. Factors such as changing connections, unknown consumption and inadequate monitoring increase the risk of overloading. This can lead to fuse blowing, equipment failure or even fire damage.
Overloading occurs when the power of one or more components (for example, cables, groups or distribution boxes) is exceeded. The consequences can range from power outages and equipment failure to dangerous situations such as fire or electrocution.
How does power distribution work in temporary installations
Importance of proper distribution
A temporary installation always starts with a proper analysis of the expected consumption. Power distribution means spreading the total power demanded over several groups and distribution boxes so that no single component is over its limit.
Role of distribution boxes and groups
Distribution boxes are equipped with fuses or circuit breakers, which provide protection against excessive currents. Each circuit is designed for a maximum load, such as 16A or 32A. It is imperative that this load not be structurally exceeded.
- Example: Connecting two heaters of 2000W each to one phase will draw about 17.4A at 230V, more than a standard 16A group can handle. This can cause the circuit breaker to fail or the wiring to overheat.
Peak consumption and concurrency
Peak consumption is when several appliances simultaneously demand the most power. This is often higher than the average consumption. Temporary installations often lack reliable monitoring, causing peaks to be underestimated.
- Whenever possible, use a concurrency factor in your calculations.
- Consider inrush currents from devices such as pumps and machinery.
Case study
For a construction site with multiple containers, lighting and power tools, the maximum power required by each component must be determined in advance, and how the sum compares to the capacity of the plant.
Choosing and applying correct cabling
Dimensioning of cables
Cables should be selected based on expected power, cable length (voltage drop!) and type of environment (indoor/outdoor, conduit, etc.).
- Rule of thumb: Always choose a cable length with sufficient margin. With longer lengths, the maximum load decreases due to voltage drop.
- Example: A 3×2.5mm² cable (16A) is not suitable to transport 3500W over more than 30 meters without risk.
Connection and transition points
Connections, plugs and distribution devices are often the weakest link. Bad contacts increase resistance and can cause heat buildup. Check them regularly and use only certified materials.
Protection against mechanical stress
Cables at temporary sites are often located in walkways or exposed to heavy equipment. Use cable bridges or protective hoses to prevent damage and short circuits.
This is what can go wrong with overloading
Blowing of fuses or circuit breakers
This is a direct response of the protection system to excessive current. Frequent occurrence indicates structural overload.
Heat generation and fire damage
Overloaded cables and connections become too hot and can melt the insulation, with a risk of fire. This risk increases with poorly maintained or outdated components.
Equipment defects
Weak or fluctuating voltage due to overloading can damage sensitive equipment beyond repair.
Safety hazards
Severe overloading or faulty installation patterns can leave parts live, resulting in electrocution or injury.
Points of interest and prevention tips
Make a thorough consumption review
Inventory the maximum power requirements of each user. Take into account expansion or unexpected new equipment.
Deploy monitoring for critical issues
Use energy meters whenever possible to monitor consumption and peaks in real time. This helps make adjustments before things go wrong.
Check and test regularly
Conduct periodic visual and metrological inspections. Test circuit breakers, ground fault circuit breakers and check temperature of critical connections.
Work only with certified installers and materials
Have installations inspected according to NEN 1010 or NEN 3140. Use only approved plugs, cables and distribution devices.
Provide good documentation and communication
Note which group feeds which device and make sure those involved know what the limits are.
Working smartly and safely with temporary installations
By considering total power, peak usage, proper wiring and regular inspection, many problems surrounding temporary installations can be avoided. Invest in monitoring and training to reduce the risk of overloading. This will increase the safety, reliability and efficiency of any temporary project.
As an experienced electrical installation company in Helmond, we advise and support temporary installations in a variety of sectors. Think of solutions such as temporary heating for a large space, supplying a customized switchboard or realizing reliable power distribution on location.
Would you like to learn more about temporary electrical services or to spar directly about your project? Then feel free to contact us.
