KNX Under RM100,000, Engineered Properly

Two 300-seat theatres with a wall of eleven switches each, a blind controller nobody could find and a projector that lecturers routinely left on over the weekend. The faculty had a written complaint from the student council and a fixed budget line that would not survive to the next financial year.

We replaced every wall switch with one plate at the lectern and one at the door. Four scenes: Lecture, Presentation, Exam and Cleaning, each one sequencing the house lights, the stage wash, the blackout blinds and the projector together. Presence detection clears the room forty minutes after the last movement, including the projector.

All of it was done inside the semester break, commissioned with the faculty technician beside us, and handed over with a laminated quick card at each lectern. The same room template has since been cloned into three more theatres by the estates office budget of the following year.

A conservation-area shoplot: café on the ground floor, a small studio let above, and an operator who could not afford to close for a single lunch service. The brief was ambience the staff could not get wrong, plus an end to the standing argument about who forgot to switch off the signage.

We worked nights and split the job into four releases, each one commissioned and tested before the next began, so the café opened every morning on a working system. Front of house runs four trading scenes on a single recessed plate - open, trade, dinner, close - with the close scene sequenced so the kitchen extract and the display cases drop out in a fixed order. Signage and façade lighting run on an astronomical clock, so nobody forgets anything again. The studio above is a separately metered zone with its own plate and its own tenant rules.

The energy metering was not in the original brief; we added it at RM3,400 because the operator could not tell us what the café cost to run. The first full month of data showed the display chillers holding a load through the closed hours that nobody had accounted for. That finding paid for the metering four times over in the first year, which is roughly the story of every energy meter we have ever installed.

An occupied unit with a finished ceiling and an owner who had made it very clear that nobody was cutting the plaster. The requirement was modest and specific: stop leaving the air-conditioning running in an empty bedroom, stop the living room being either fully bright or fully dark, and be able to check the whole unit from the airport.

Wired KNX was out on the ceiling side, so the installation is a hybrid: twisted-pair bus run inside the existing switch loops and the DB where the containment already existed, and KNX RF for the two bedroom points where it did not. Ten circuits, three air-conditioning zones on IR gateways, one blind, five plates. The whole job was surveyed on a Saturday, cabled and programmed across three weekdays, and commissioned before the weekend.

The point of the story is not the price. It is that a RM16,900 system in a condominium later let out still left the owner holding an ETS project file, a labelled DB, a device inventory with warranty dates and a signed test sheet. When she sells that unit, the buyer inherits a system any certified integrator on earth can take over. That is worth considerably more than the difference between us and a hub in a cupboard.

The house was bought with a KNX system already in it and no file, no drawings, no passwords and no installer - the company had wound up. Half the ground floor no longer responded to anything. Two contractors had already quoted to strip it out and start again, at RM120,000 and RM145,000, which is what happens when nobody wants to take responsibility for somebody else's work.

We spent four days on the bus before quoting anything: reading device addresses off the live line, mapping what physically responded to what, opening every DB in the house and photographing it. Eighty-one of the ninety-four devices were healthy certified hardware. The dead zone turned out to be a failed power supply on an unsegmented second line that had been loaded well past sensible - the original fault was a design decision made years earlier, not a device.

The recovery came to RM41,300: a new supply, a line coupler and proper segmentation, thirteen device replacements, a rebuilt and fully documented ETS project, and re-labelling throughout. The owner kept RM79,000 of working hardware that two other firms had written off. He also, for the first time, owns the file.

A multipurpose hall and adjoining rooms, run by a volunteer committee that changes every two years. Every previous system in the building had failed the same way: it worked until the one person who understood it stopped being on the committee.

So the constraint drove the whole design. The hall has one plate at the entrance with four labelled modes and nothing else - the sound reinforcement, the fans, the lighting levels and the air-conditioning for each mode were argued out with the committee during design and then locked. There is no app requirement to operate the building. There is an app, and no volunteer is ever obliged to open it.

The RM88,400 covers the hall, two meeting rooms, the kitchen, external and car-park lighting on an astronomical clock, and sub-metering so the committee can see what an event actually costs to hold. The handover pack is written for someone with no technical background, and the annual maintenance visit is timed to land just after the committee changes over, so the new chairman meets us in his first month rather than during his first fault.

A small developer with eighteen units wanted a genuine automation story for the launch and had been told, correctly, that KNX would not work at his price point. It would not have, quoted the usual way: eighteen individually engineered units at typical design rates puts the per-unit figure somewhere no boutique project can absorb.

One unit was engineered, programmed, tested and signed off as the template - that unit carried the real cost. Every unit after it is a replication: its own ETS sub-project, its own serialised device schedule, its own test sheet, but no new design work. The per-unit price landed at RM19,200 and, more usefully for him, it was a number he could commit to in writing before the first slab.

The block was released in three groups of six to follow vacant possession. Each buyer received a per-unit handover pack, and the JMB received the block-level documentation and a maintenance proposal at handover of common property. This is the same method we use on towers. There is no minimum size at which it starts working.