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Could you look into the practicalities of using presence detectors for controlling the lights in
different parts of the building? We’ll probably have a mixture of detector- controlled systems
and manual switches. The question is, which type of control do we want to have in each
location? (Please see my list below.) A critical issue will be setting the switch-off delay in
different locations, i.e. how long the lights remain on after the last movement is detected. On my
last project, we had a lot of complaints | from the client about the lights going off while people
were still in rooms. So can you think about different timer delays for different locations in the
building?
Main locations: open-plan offices, individual offices, meeting rooms, corridors, store rooms

c Prepare notes for a short talk to brief the project engineer using your ideas from
Exercise 3b. Student A, you are an M&E engineer. Brief the project engineer on your
ideas. Student B, you are the project engineer. Read the briefing and ask questions about
specific details. Swap roles and practice again.

II Referring to measurable parameters

4 In pairs, think of monitoring and control systems that are widely used around the home.
Discuss how the following parameters are measured and/or controlled in these common
domestic appliances.
Parameters: temperature; pressure; time; actions/movement;
Appliances: boilers; heating; systems; refrigerators; washing; machines;

5 a Match the sensor or measuring system (1 -5) to the industrial applications(a-e).
1 pressure measurement
2 temperature measurement
3 flow measurement
4 level measurement
5 process recorders

a monitoring the speed of water travelling along a supply pipe
b measuring the level of heat generated by an exothermic reaction
c monitoring the number of cans moving along a conveyor belt
d monitoring the amount of ethanol contained in a storage tank
e checking the force exerted by steam inside a vessel

b In pairs, think of other uses for the kinds of sensor and measuring equipment in Exercise
5a.
6a ► 8.4 Jochem and Katerina, two process engineers at a chemicals plant, are discussing
the monitoring and control systems that will be needed for a new production line. Read
three extracts from their discussion and answer the following questions.
Extract 1 a What problem is discussed?
b What mechanical safety precaution is proposed?
Extract 2 c What issue is discussed?
d What three parameters related to consumption are important?
e To calculate the parameters, what does consumption need to be
continuously measured against?
Extract 3 f What issue is discussed?
g Which two measurements need to be taken?
h What optimum value needs to be determined?

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