Richard Webb, Regional Specification Manager at Waverley, explores the options for automating blinds and discusses common pitfalls.
As architects and designers strive to improve the sustainability performance of new and existing buildings, automated blinds are becoming more and more important in achieving these goals and the cost of automation is reducing – if well managed.
The bigger picture
An important element in the successful implementation of the overall package is often overlooked and that is the control protocol chosen and the accompanying cabling requirements. The tendency is to look at ‘blind cost’ and ‘electrical installation’ in isolation, whereas a more holistic approach, taking both into account could prove beneficial.
For example, choosing a more expensive motor/control may well result in considerable reductions in cabling, containment and commissioning – reducing the overall cost of the project. Looking at each item individually doesn’t give you the full picture.
Different projects, different controls
The choice of control will always be different for different projects, there is no ‘one for all’ solution. Control choice is driven by many factors, including the size of the building, complexity/functionality of control required and number, type and size of blinds themselves.
Pictured: Waverley’s installation of automated roller blinds throughout Centre Point were all operated via a Crestron Control System
As building systems become increasingly complicated, it is also important to eliminate, or reduce as far as possible, any points in the supply and control cabling that could be prone to faults. This reduces on-site commissioning, set up time and ongoing maintenance of the building.
The earlier the better
The control and wiring should be considered in the design at an early stage in the program to ensure that all stakeholders are aware of both the requirements and their responsibilities. All too often, the situation arises on-site where the blind install contractor arrives on-site and no or inadequate power provision has been made, necessitating costly additional cabling and conflict between contractors for who bears the brunt of the costs. This can be easily addressed by simply exploring different control and power options at the design stage.
Discussing control and power options at the design stage will save time and money later on in the process
Types of control solutions & other considerations
As mentioned, the types of control solutions vary from project to project, but there are some rough guidelines on which types of control are suitable for projects of varying size and complexity. I discuss these below.
Hard-wired control solutions
Simple hard-wired switching and motor control boxes provide a tried and tested method of allowing reliable control of both individual and group control of blinds. Whilst perfectly suitable for smaller projects they tend to be ‘cable heavy’ and on larger projects the amount of cable and the multiplication of ‘fault points’ can considerably add to the cost and install/commissioning time.
Fig 1. Typical Mechanical motor system with hardwired switching
Radio control solutions
Radio control is a simple and effective method of providing flexible control of individual or groups of blinds. It reduces the cabling requirements as no cabling is required to the switch points and again can be very suitable for smaller projects. On larger projects what is often overlooked is the cost of providing a 230v fused spur or outlet to every blind position can far outweigh the extra costs for more advanced motors.
Fig 2. Typical Radio motor system
Digital control solutions
Most large automated blind projects will utilise a digital motor, as this gives great control flexibility, and enables precise positioning of the blinds. There are several different systems available, but to get the best value for money it is important that the clients requirements are fully understood before choosing a control solution.
e.g. the requirement for very quiet motors may direct along one route whereas the requirement for the most control within a certain budget will direct a different route.
Other requirements which may influence the decision could include future-proofing – such as the requirement for open protocol or the acceptance of proprietary protocol. If you’d like advice, feel free to reach out – we’d be more than happy to help.
Fig 3. Typical digital motor system.
Consideration also needs to be given to containment. Low voltage solutions will require separate containment runs from any mains voltage cabling, and many 230v systems still rely on a separate data cable to control the motor. This needs to be routed in a segregated containment solution. Again, if this is planned at the design stage, there’s likely to be no issues.
Reducing fault points
As briefly mentioned, another very important aspect is the elimination or reduction of ‘fault points’. Every individual wire connection represents a potential fault point that affects both power and control cable connections. All on-site cable connections have to be tested, and if a fault is found, it can take considerable time to trace and correct, all adding to the time and costs incurred.
Control Example – SMI Digital
Use of the SMI protocol blind motors and controls can considerably reduce cabling, containment requirements along with potential fault points as indicated.
Fig 4. SMI digital
When this is combined with pre-made motor cables BUSbar cabling and virtually fault-proof cable connectors the amount of fault points and time on site is further reduced see Fig 5.
|Per 16 motors||SMI CR ID||Typical Digital Motors||Mechanical Motors|
|Typical cable length (m)||84||184||184|
|Cores / Terminations||240||464||352|
|Controls / Plugs (Qty)||16||56||20|
|Points of failure||304||608||464|
Fig 5. Comparison between SMI, standard digital motors, and standard mechanical motors.
This brief article seeks to demonstrate the importance of considering the many factors and nuances involved in automation blind control as early as possible in the design process. Choosing a control system in good time lays the groundwork for smooth installation and integration with the rest of the building, whilst giving the opportunity to consider the cost implications of different options.
How we help
At Waverley, we work with specifiers to turn their design concepts into workable proposals that meet their client’s needs. If you need help determining which control system is right for you, feel free to contact us, and we’ll work together to find the best solution.