Crestron control systems explained

A Crestron control system ties together the displays, cameras, audio, lighting, shades and other equipment in a room or building so people can operate them from one touch panel or keypad. Instead of five remotes and a wall of switches, a user presses "Present" or "Start meeting" and the system does the rest. The hardware is only half of it: every system is programmed for its site, and that programming is what makes it easy or frustrating to use.

What a control system does

Modern rooms contain many devices from different manufacturers, each with its own controls. A control system:

• Turns equipment on and off in the right order
• Switches sources and routes video and audio to the right displays and speakers
• Sets lighting and shades for presentations or video calls
• Combines or divides rooms with movable walls
• Reports equipment status and faults to support staff
• Can schedule shutdown at the end of the day to save energy and extend equipment life

Crestron is one of the best-known makers of control systems; others exist. The concepts here apply broadly.

The main parts

Control processor

The processor is the brain. It runs the program and talks to every device over the network, serial connections, infrared or relays. Some products combine the processor with switching or with a touch panel for smaller rooms.

User interfaces

Touch panels on the table or wall, keypads at the door, and sometimes apps on phones or tablets. A good interface shows only what users need, in plain language.

AV switching and distribution

Video and audio signals need to get from sources (laptops, room PCs, cameras) to displays and speakers. This can be done with traditional matrix switchers or with AV-over-IP, where video is encoded and sent over a dedicated network. Crestron's DM NVX line is an example of AV-over-IP. It scales well across many rooms but needs a network designed for it, with suitable switches and multicast configuration.

Lighting, shades and environment

Control systems can integrate lighting dimming, motorized shades and sometimes HVAC setpoints, so the room is set up with one press. Integration with building automation should be coordinated with whoever manages those systems; see building automation systems.

Remote management

Crestron and other manufacturers offer cloud or server-based tools for monitoring rooms, pushing firmware and reporting usage. Crestron's XiO Cloud is one example. These tools let support staff see a failed device before users report it.

Every one of these parts lives on the network, so the control and AV systems should be planned with your IT team from the start rather than added to the office network at the end.

Programming: the part that matters most

Unlike consumer devices, a Crestron system does nothing useful until it is programmed for the site. A programmer writes the logic that links each button to the right sequence of commands, and designs the touch panel screens. Good programming makes a room feel simple. Poor programming produces confusing screens, slow responses and rooms that work only if you press buttons in a certain order.

What to ask for

• A written description of how each room should work, agreed before programming starts
• Consistent interfaces across rooms of the same type
• Programming by Crestron-trained programmers
• Source code, compiled files and credentials handed over and stored safely
• As-built drawings, device lists and IP address schedules
• Network design for control and AV-over-IP traffic, coordinated with IT
• Security settings: changed default passwords, current firmware, restricted access
• User training and a support plan

A typical case: a divisible training room

Divisible rooms show why programming matters. Picture a training room with a movable wall that splits it into two rooms, each with its own display, ceiling microphones, speakers and touch panel. Users expect it to behave like two rooms when the wall is closed and like one large room when it is open. The program has to handle:

1. Detecting the wall position. A sensor on the partition tells the processor whether the wall is open or closed, so the system changes mode without anyone choosing it.
2. Combining audio. In combined mode, microphones from both halves feed one mix, speakers play throughout, and echo cancellation settings change to suit the larger room.
3. Routing video. A source selected on either panel appears on both displays, or each display can show something different if the presenter wants.
4. Linking the panels. Either touch panel controls the whole room in combined mode, with the same screens, so it does not matter which one people walk up to.
5. Lighting and shades. One press sets the whole space for presentations or video, rather than two separate scenes.
6. Returning to normal. When the wall closes, each half returns to its own settings without leftover routing or muted microphones.

Every one of these behaviours has to be described, programmed and tested. Missing one, such as microphones staying combined after the wall closes, is the kind of fault that makes users stop trusting the room.

What a room functional description covers

Before programming starts, the integrator and the client should agree on a written description of how each room will work. It usually covers:

• Every source and destination, and which sources can go to which displays
• What happens at power-on, at the start of a meeting, at the end and at shutdown
• Each touch panel page, with the buttons and the words on them
• Lighting and shade presets and when they are used
• Room combining behaviour, if any
• Integration with calendars, conferencing platforms and building systems
• What status is reported to monitoring, and who gets alerts

Testing at handover then checks the room against this document, function by function.

Is it worth it?

For a small huddle room with one display and a video bar, a full control system is usually unnecessary. For boardrooms, divisible rooms, auditoriums, training centres and buildings with many similar rooms, a control system makes rooms consistent, easier to support and easier to use. For room planning, see boardroom AV design.

How ehZee can help

Our Crestron control systems service starts by asking how each room will be used, then designs the system and network, builds and programs it, and tests every function before handover.

Common questions