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UNIT 8 MONITORING AND CONTROL

I Describing automated systems

1 In pairs, discuss the difference between an automated and a manual system. What do
you think a Building Management System (BMS) does in intelligent buildings? Suggest
some operations that can be monitored and controlled automatically by the BMS in large
buildings such as offices.

2a ► 8.1 Roland, a mechanical and electrical services (M&E) engineer, is talking to
Saskia, an architect, about the design of a new building. Read the conversation and answer
the following questions.
1 What is a key characteristic of the client company?
2 How will this characteristic affect the building design?
3 What do you think is meant by presence detectors?
4 What does Roland say about design options and how does he describe option one?

Roland: We know the client is a very green orientated company, very big on all things
environmental.
Saskia: Absolutely.
Roland: So energy saving obviously needs to be an important consideration in the design.
Clearly, it’s a big subject, and something we need to look into in depth. But one specific aspect
of it where I think we can make a real difference is with the Building Management System -
specifically, with the way we use presence detectors. And I’ve had a couple of ideas that I’d
appreciate your views on.
Saskia: Sure.
Roland: I think we should put two totally different design options to the client. Option one is to
have a building with maximum automation. So with the maximum automation option ...

b 8.2 Roland gives some examples of sensors and controls. Read the next part of the
conversation and tick the points he mentions.
1 controlling the electric lighting inside the building
2 controlling the amount of solar radiation entering the building
3 controlling the air flowing in and out through the windows of the building
4 controlling the flow of warm and cool air around the interior of the building

Roland: ... with the maximum automation option, we put presence detectors all over the place,
and link them to as many systems as possible. Not just the usual systems that activate the lights
when people walk into rooms and turn them off when they leave. We could use presence
detectors to control other systems, as well, like the blinds on the windows. So, if it’s the middle of
summer, and a presence detector senses that everyone's left a meeting room, a temperature
sensor picks up a positive reading from sunlight coming through the glass, the electronics
activate the blinds, which automatically come down and black out the room. That would limit
heat absorption and reduce the load on the air- conditioning, saving energy.
Saskia: OK.
Roland: Or in winter, if the blinds had been pulled down in the meeting room the evening before,
the next morning, the sensor detects sunlight, and triggers the blinds to raise and let in as much
sunlight as possible, contributing to the heating. And there could be temperature measurements
to determine which rooms are the warmest, and those sensors set off a circulation system to

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