14. Figure 3.
Room stat
2
2
C
Blue (neutral)
White
Grey
Grey White
Orange
Switch
live
(heating)
Switch
live
(hot water)
Neutral Earth
1
1
4
3
Cylinder
stat
Water control
zone valve
Boiler
terminals
Pump
motor
Programmer
230V
50Hz
L
L
L
N
N
N
E
E
E
On
On
Off
Off
Heating
Hot water
Orange
Yellow/green
FIGURE 3.Sources technical information and communications
69
electrical elements circuit.
Freehand working diagrams
Freehand working drawings sketches are another important way in
which communicate our ideas.39) were done from freehand sketches.6 shows schematic diagram. should also contain all the dimensions
necessary indicate clearly the size the finished object depicted the
sketch.
To convey the message information clearly better make your
sketch large rather than too small. electrical schematic diagram looks very like circuit dia-
gram. The drawings the spring toggle bolt
in Chapter (Fig.
. freehand
sketch may done initial draft idea before full working draw-
ing made.4
Wiring diagram space heating control system (Honeywell Plan). often much easier produce sketch your ideas or
intentions than describe them produce list instructions. These help understand the working
operation the circuit but are not helpful showing how wire the
components
