Elenco Basic Electricity User Manual

WARNING: Always check your wiring before

urning o n a c ircuit. Never leave a ci rcuit

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unatte nded while the batteries are i nstalle d.

ever connect additional batteries or any other

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power sources to your circuits.

Project 1 Lamp Current Project 2 Batteries in Series

Basic Electricity

Model SCP-10

ARNING: SHOCK HAZARD -

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Never connect Snap Circuits
to the electrical outlets in your

ome in any way!

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®

Placement

evel Numbers

1A

Electricity is the movement of sub-atomic charged
particles through a material due to electrical pressure
across the material, such as from a battery. Power
sources, like batteries, push electricity through a circuit,
like a pump pushes water through pipes. Wires carry
electricity, like pipes carry water. Devices like lamps use
the energy in electricity to do things. Switches control the
flow of electricity like valves and faucets control water.

The electrical pressure exerted by a battery or other
power source is called voltage and is measured in volts
(V). The “+” and “–” signs on a battery indicate which
direction it will “pump” electricity.

The electric current is a measure of how fast electricity
is flowing in a wire, just as the water current describes
how fast water is flowing in a pipe. It is expressed in
amperes (A) or milliamps (mA = 1/1,000 of an ampere).

The “power” of electricity is a measure of how fast energy
is moving through a wire. It is a combination of the voltage
and current (Power = Voltage x Current). It is expressed in
watts (W).

The resistance of a component or circuit represents how
much it resists the electrical pressure (voltage) and limits the
flow of electric current. The relationship is Voltage = Current
x Resistance. When resistance increases, less current flows.
Resistance is measured in ohms (W).

L

Snap Circuits®uses electronic
blocks that snap onto a base
grid to build different circuits.
These blocks have different
colors and numbers on them so
that you can easily identify
them. Build the circuit shown by
placing all the parts with a black
1 next to them on the clear base
grid first. Then, assemble parts
marked with a 2. Install three (3)
“AA” batteries (not included)
into the battery holder (B3).

Set the meter (M5) to the 1A
setting.

Turn on the slide switch (S1).
The lamp (L4) comes on, and
the meter measures how much
electric current is flowing.

5V

Set the meter (M5) to the 5V setting, and turn on the slide
switch (S1). The lamp (L4) comes on, and the meter measures
the voltage from the 3 batteries.

Part B: Remove the left battery from the holder (B3), then snap
one side of the red jumper jumper on as shown, and touch
metal on the other end to the left spring in the battery holder.
Read the voltage on the meter, measuring 2 batteries, and
notice how the lamp is dimmer.

Part C: Now also remove the center battery from the holder and
touch metal on the end of the red jumper wire to the center
spring in the holder. Read the voltage on the meter, measuring
1 battery, and notice how the lamp is dimmer.

If desired, use the voltage measured here (with 3 batteries) and the
current measured in project 1 to calculate the resistance and power of
the lamp:

Resistance equals Voltage divided by Current, and should be about 15
ohms. Power equals Voltage times Current, and should be about 1 Watt.

Your results may be different, because M5 is a simple meter with low
accuracy, and your battery voltage can vary.

Batteries are like electrical pressure, pushing electricity
through a circuit. Adding more batteries increases the
flow of electricity, making the lamp brighter.

Part B:

Part C:

Quiz answers:

1. B 2. B 3. C 4. A 5. B

If you have any problems, contact Elenco

®

Copyright © 2014 Elenco®Electronics, Inc. All Rights Reserved. ● 150 Carpenter Ave. ● Wheeling, IL 60090

[phone] Fax: [phone] ● e-mail: [e-mail] ● Website: www.elenco.com or www.snapcircuits.net

753159

Project 3 Triple Voltage Divider

Placement

evel Numbers

L

5V

The circuit has three lamps connected in series, or two when S2 is pressed (S2 bypasses the last one).

A. Point A is the “+” battery terminal, so the meter is always measuring the battery voltage.

. When S1 is on, point B is connected to the batteries, so the voltage will be the same as point A. When

B

S1 is off, the voltage is zero.

C. Point C measures the voltage after one lamp and across the other two, so should be about 2/3 of the

battery voltage. When S2 is pressed, the last lamp is bypassed, so point C is measuring across one of

he two remaining lamps, so should be approximately 1/2 of the battery voltage.

t

. Point D measures the voltage after two lamps and across the last one, so should be about 1/3 of the

D

battery voltage. When S2 is pressed, the last lamp is bypassed, so point D is zero volts just like point E.

E. Point E is the “—” battery terminal, and will always be zero.

Kirchhoff’s Voltage Law, an important rule for analyzing circuits, says the total voltage driving a circuit must
equal the voltage drops within it. So the voltage drops across all of the lamps should equal the battery
voltage. (Your measurements may be a little different, because M5 is a simple meter with low accuracy.)

This circuit is pictured on the front of the box, use that picture to help
in building it. Set the meter (M5) to the 5V setting. Turn on the slide
switch (S1) and use the meter to measure the voltage at points A, B,
C, D, & E in the circuit by connecting the end of the red jumper wire
to each of those points (the drawing shows it connected to point C).

Next, repeat the voltage measurements at points A, B, C, D, & E
while pushing the press switch (S2).

Project 4 Heavy Load

5V

Set the meter (M5) to the 5V setting,
and initially keep the switch (S1) off.
The meter measures the battery
voltage with the lamps (L4) off.

Now turn the switch on to light the
lamps, and see if the battery voltage
changes. Next, remove one or two of
the lamps and compare the voltage.

Try this project with both new strong
batteries and with old weak ones.
Compare how the voltage changes
when you turn the switch on.

Batteries produce electricity using a chemical reaction,
and only a limited amount of the chemicals can react
together at once. Also, the chemical reaction slows as the
batteries get weaker. When a circuit wants more
electricity than the batteries can supply, the voltage
(electrical pressure) drops.

In this circuit, lighting all three lamps takes a lot of
electricity, so the voltage drops a little when the switch is
turned on. The drop in voltage is much greater for weak
old batteries than for strong new ones.

Project 5 Heavy Flow

Modify the preceding circuit
to match this one. Set the
meter (M5) to the 1A setting
and turn on the switch (S1).
The meter measures the
current. Try removing one
or two lamps and see how
the current changes. Also
try this circuit with both new
strong batteries and with old
weak ones.

1A

In this circuit, electricity flows out
of the batteries, through the meter,
then divides among the 3 lamps,
then all flows back to the batteries
through the switch.

The 3 lamps are connected in
parallel, because the current flow
divides among them. If one of the
lamps burns out, the others will
still work because has its own path
for electricity to flow along.