Chapter 4, Problem 1SQ

Identify the following symbols.

To determine

Identify the given symbols.

Explanation of Solution

Discussion:

The names of the symbols are provided in Table 1.

Table 1

Part	Name of the symbol	Description
a.	Normally open, momentary contact push button.	It is a type of push button, through which two contacts are closed or opened at a time.
b.	Double-acting, momentary contact push button.	It is a type of push button, through which two operations can be performed using single push button.
c.	Mushroom head, normally closed, momentary contact push button.	It is a palm operated push button.
d.	Normally open pressure switch.	It is a type of pressure control relay.
e.	Normally closed float switch.	It is a type of pilot devices. It controls the circuit through single contact.
f.	Three-phase squirrel cage motor.	It is a type of motor.
g.	Current transformer.	It is a type of transformer that is mostly used in large motor starters to step down the current.
h.	Three-phase disconnect switch.	It is a type of switch that is used to disconnect the three phases from supply.
i.	Normally open contact.	It is a type of switch, in which no current flows in the circuit.
j.	Normally open, on-delay timer contact.	It is a type of timed contacts.
k.	Normally open, off-delay timer contact.	It is a type of timed contacts.
l.	Normally open limit switch.	It is a type of limit switch.
m.	Node point showing connected conductors.	It is a point at which two or more conductors are connected.
n.	Red pilot light.	It is mostly used for the indication of pilot lights.
o.	Normally open switch (single-pole single-throw switch).	It is a type of switch. By single throw, the switch can be either opened or closed.
p.	Double-break switch.	It is a type of switch, in which two contacts are to be opened or closed at a time.

Conclusion:

Thus, the names for the given symbols are provided.