1.      System Design: The first stage of installing a control network is design.  During the design process the location of all zone sensors must be identified.  This is typically done by the design team.  Unfortunately, it is often necessary to locate sensors on the plans without detailed information about how the space will be utilized.   

This often results in sensors being mounted behind cabinets, on columns, exterior walls, in the path of bright sunlight,  or behind a stray coffee pot.  Moves after construction is complete are expensive and require not only running of wires through completed walls, but patching existing surfaces.

Sensor locations on plans are only a recommendation.  Final sensor locations can be determined once all of the furniture and wall finishes are complete.

2.      Equipment Rough In: The controls contractor’s electrician need to show up at the project site at the point where partitions are framed but not yet sheathed.  At this time, they run in the sensor cable either within the wall framing or in many areas, using a conduit drop.  Wiring is left roughed in and not connected. 

Roughed in wiring requires a close level of coordination with other construction trades.  Since the controls contractor electrician is not always on the job site this can be a problem.  Also, on many projects, there is a need to have temporary heating or cooling.  In order to provide this, a temporary sensor has to be mounted at the terminal unit. 

No rough in required.  Temporary heat or cooling can be easily accommodated with a wall or unit mounted sensor. The terminal units can be installed by the mechanical contractor.  Controls can be factory mounted or field mounted by the controls contractor at any time.  If a wired controls communications network is used, it needs to be roughed in above the ceiling, however this communications can also be wireless, combining factory mounting of controllers and wireless communications means that the controls contractor does not need to be at the job site until it is time to do startup.

3.      Sensor Installation: Once the wall sheathing and final finish is completed, the zone sensors can be installed.  This installation requires the removal of any temporary sensors, and installation of the permanent sensors.  Note:  Temporary sensors will often be damaged by paint and other construction debris and typically can’t be used for final installation. 

The installation of the final sensors is required to finish the building and receive a certificate of occupancy which requires final dry-walling, paint, paper, etc. to be completed.  Again this is a coordination challenge that may require multiple trips to the jobsite to install sensors.  Unfortunately, once the sensors are installed, they can be easily damaged by moving crews locating furniture and other material into the building.  Damaged sensors may result in controller damage and require replacement at the owner’s expense.

The wireless sensors can be brought to the project site near to project completion.  They can be mounted in the most optimal location onto any surface.  In many cases, they are mounted to cubicle partitions, walls or columns, making sure to place them out of sunlight or other problem areas.