K3Schematic Analysis

and

Pictorial Diagram

Turn to page K3 in the Student Handout Packet

Answer the following questions.

What type of single phase fanmotor is used on this equipment?

You should notice there are no starting

relays or capacitors. It can only be a

Shaded Pole.

Does the fan and limit have a jumper?

Refer back to K1 if you need help

in answering this question.

Your answer should be: YES

This circuit is for heating and cooling. It also

includes an electronic air cleaner (EAC).

What is the switching action of the FR?

Your answer should be: DPST. There are two

inputs: one from L1 (H) and the other one from

the NO contacts of the FL.

What is the switching action of the EAC?

This EAC is deceiving because it appears as if there

are two inputs. But a more educated analysis will

indicate it is nothing more than a mirror image of a

SPDT relay.

But is the EAC really a SPDT? Go to the

PICTORIAL on page K3a and check it out.

When you look at the pictorial, you should

determine that it is a DPST – 1NO, 1NC

You will now draw the

Pictorial

by following the

Schematic

The process will be to follow the schematic one

wire at a time from one component to another

component until we are finished.

The slides that follow will show the wire in RED

on the schematic that is going to be wired on

the pictorial. Then the pictorial slide will show

that wire being ‘installed.’ That is the wire you

are to place on your pictorial. Keep advancing

through the slides until you are finished with

the pictorial.

Turn to page K3a and you will see, at the top of

the page, that this page is to be used to wire

the POWER circuit.

Turn to page K3b and you will see, at the top of

the page, that this page is to be used to wire

the CONTROL circuit.

So let’s begin with K3a and the POWER

circuit first. This will be a very difficult

schematic to follow because it will seem

as if the wires go everywhere.

Sometimes it is best to check off the wires

as you ‘wire’ them.

WOW! You finished the POWER circuit.

You have finished the

POWER pictorial

following the

schematic

Move onto K3b and the CONTROL

circuit. This will not be as difficult as the

POWER circuit.

You have finished the

CONTROL pictorial

following the

schematic

You have finished the

entire project.

CONGRATS