It is crucial for retailers to have complete electrical drawing packs and full specification data, in digital form, for all our fixtures so that we can make swift and accurate design, development and procurement choices. Supporting documentation is also essential to meet increasingly demanding Health & Safety requirements and to protect customers, our business, and our suppliers.
The following is a list of the minimum information required to complete electrical technical drawing sheets. All drawing dimensions, notation & information must be legible when printed on A3 paper size.
All sheets must have a drawing boarder that includes:
Third party and ‘off the shelf’ items must be clearly identified and marked with the appropriate supplier details, including:
General Electrical Assembly drawings
The drawing provides details on how all components are connected and installed either within the display or standard alone. A template is available within the dc guide and includes:
Component Electrical Assembly drawings
The drawing provides details on how components are built and must include all sub-component used in the assembly. A template is available within the dc guide and includes:
Reductions in cable size or current require fuse protection. Every display should be divided into circuits to:
To allow for standardisation of sub-components, circuit types have been divided into 4 electrical zones. This allows the following benefits:
All electrical equipment generates heat so consideration should be given to the effect of exposure to extreme temperatures. Heat has a degrading effect on electrical components, and poor design can lead to:
Electrical equipment needs to be easily accessible for inspection, testing, maintenance and repair. Ensure that access is not significantly impaired by the shop-fitting, displays or signage.
Access to sockets should be restricted or limited to ensure store staff do not misuse them or allow them to become overloaded.
The electrical designer needs to consider the life expectancy of components and subcomponents. This will vary depending on whether the display is permanent, semi-permanent, or temporary, as well as the type and quality of components used.
The life expectancy of the electrical components, particularly LEDs, has an impact on the type of subcomponents that can be used.
The electrical designer should establish the difference between expected life, warrantied life, and likely hours of usage, and consider how the choice of components will affect the cost.
The electrical systems must be modular and inter-connectable rather than hardwired as this will ensure that the system is easier to install, maintain, and repair.
Connectors should be:
Where possible make use of dc approved, standardised components as this:
When using these components, designers must work to the manufacturers’ guidance including operating temperatures, fixing methods or locations
The use of commonly used electrical components has many benefits:
Purchase Costs & ROI
To keep purchase costs down, the designer should perform research and due diligence on products and suppliers. It is important to specify exactly the performance requirements that the products need to meet. Quotations should be obtained from multiple sources.
The cost of similar products can vary a lot, but the key factors to consider are:
Typically, the largest ongoing costs relating to store interiors and display equipment are:
It is important to review all associated costs before selecting equipment.
The following chart shows a breakdown of the main cost considerations, including the lifespan of the product, its expected usage and frequency of replacement.
An example of the calculations for determining for return on investment (ROI) has been included.
All display, signage and shop fit equipment needs to be isolated in the event of failure.
It is the responsibility of the electrical designer to determine where the isolation points are within the store and that store staff and user know the points of isolation.
The electrical contractor has a responsibility to provide clear identification of isolation points that must indicate:
The manufacturer of the equipment has a responsibility to ensure that it is immediately obvious to the responsible person where the point of isolation is for each electrified display. The location of each control/isolator should be indicated in such a way that no confusion should occur.
Where the point of isolation is not immediately obvious, the manufacturer must provide suitable documentation/drawings/diagrams to clearly indicate the location of the point of isolation. This documentation should be readily available to all in-service shop staff and kept up-to-date by a responsible person (for example, a store manager or nominated duty holder).
When electrified display units are replaced, the responsible person should check the accuracy of the documents. They need to make sure that the documentation is kept up-to-date and accurately describes the location of the isolation points.
Maintenance and Installation
For maintenance and installation, consider the following in the design:
For each display, it is necessary to provide installation instructions that are easy to understand. The instructions should include mechanical fixing and electrical connection points as well as the electrical load capacity.
The aim must be to keep maintenance to a minimum. Having spare fuses to hand can help to prevent the need for re-visits, especially when the fuses are specific to the equipment.
The need for onsite work should be kept to a minimum. Display units should be designed and manufactured so that they can be installed and maintained with minimal need for onsite work. Connections to the mains power supply should be through a flexible cables and connectors to avoid hardwiring.