The
purpose the block diagram show how the components the circuit
relate each other and, therefore, the individual circuit connections are
not shown. All the essential
parts and connections are represented their graphical symbols. Figure 3.5 shows the circuit diagram of
our same space heating control system. Figure 3.
Block diagrams
A block diagram very simple diagram which the various items or
pieces equipment are represented square rectangular box. They not indicate how a
piece equipment circuit works. It
will laid out clearly possible, without regard the physical lay-
out the actual components and, therefore, may not indicate the most
convenient way wire the circuit.68
Basic Electrical Installation Work
intake position other sub-mains positions.2 Chapter 5
are circuit diagrams.
.3
Block diagram space heating control system (Honeywell Plan). The purpose wiring diagram is
to help someone with the actual wiring the circuit.4 shows the
wiring diagram for space heating control system. Figures 5.4–4.
Wiring diagrams
A wiring diagram connection diagram shows the detailed connections
between components items equipment. Figure 3.
Circuit diagrams
A circuit diagram shows most clearly how circuit works.7 Chapter 14.1 and 5. The
purpose circuit diagram help our understanding the circuit. Other wiring diagrams
can seen Figs 4. uses graphical symbols indicate the interrelationship the
Fuel supply
Fuel control
valve
Room
thermostat
Cylinder
thermostat
Controller
Programmer Pump
Boiler
FIGURE 3.3 shows the block diagram space heating control
system. The site the sub-mains and
the route taken the distribution cables may shown blank copy of
the architect’s site plan the electricians ‘as-fitted’ drawings.
Schematic diagrams
A schematic diagram diagram outline of, for example, motor starter
circuit