3B Scientific High Current Coil with Five Turns User Manual

3B SCIENTIFIC® PHYSICS

Coil with 5 turns 8497320

Instruction sheet

08/ALF

1 Coil with 5 turns
2 Insulating sleeve
3 Clamping device
4 Contact pins
5 Wooden handle

1. Safety instructions

When using the coil with 5 turns, extremely high
temperatures are generated during the course of
the experiments.

Caution: during spot welding experiments, sparks
may jump from glowing metal droplets. Caution:
As a result of the action of gravity, the glowing part
of the melting nail drops downwards in the ex­periment requiring the melting of a nail.

• Conduct the experiment on a heat-resistant

surface.

• After completing the experiment, allow the

apparatus to cool for at least 5 minutes.

• Always switch off the primary voltage before

undertaking any assembly/set-up work on the
transformer.

• Limit the duration of the experiment to a

maximum of approximately 30 seconds.

2. Description

The coil with 5 turns is used as a secondary coil in a
high-current transformer in experiments to dem­onstrate the application of Joule heat.

The coil consists of a copper wire which has been
wound around an insulating sleeve in 5 turns. The
extended ends of the coil are fitted with wooden
handles. The contact pins are held in place with
the help of a clamping device.

3. Technical data

Secondary side of the high-current transformer
Short-circuit current: 350 A approx.
Open-circuit voltage: 2.4 V approx.

Number of turns: 5
Wire gauge: 28.25 mm

2

Material: Copper

4. Sample experiments

In order to conduct the experiments, the following
apparatus is additionally required:

1 Mains coil 8497420
1 Transformer core

with yoke and clamps 8497180
1 Set of sheet metal strips 8497330 or
1 Set of nails 8497331

1

4.1 Spot welding

• Set up the high-current transformer as shown

in Fig. 1 and place it on a heat-resistant sur­face.

• Attach the contact pins so that they face one

another.

• Switch on the web coil and hold a pair of sheet

metal strips between the contact pins.

To achieve a strong point weld, take two identical
overlapping sheet metal strips and align their cor­ners. Apply gentle pressure and position the cor­ners flush between the electrodes.

4.2 Experiment for melting a nail

• Set up the high-current transformer as shown

in Fig. 2 and place it on a heat-resistant sur­face.

• Turn the clamping device and insert a nail

through the holes at the sides.

• Press the handles together and clamp the nail

tight with the hand screws.

• Switch on the mains coil.

Owing to the strong current, the nail starts glowing
and melts completely after a short while.

• After conducting the experiment, allow the

remains of the nail to cool for at least five
minutes.

600

Fig. 1 Spot welding

600

Fig. 2 Experiment for melting a nail

Elwe Didactic GmbH • Steinfelsstr. 6 • 08248 Klingenthal • Germany • www.elwedidactic.com

3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com

Subject to technical amendments.