PASCO ES-9057B User manual

Instruction Sheet
for the PASCO
Model ES-9057B
CHARGE PRODUCERS AND PROOF PLANE
012-07144A
5/99
$1.00
© 1994 PASCO scientific
Introduction
The PASCO ES-9057B Charge Producers and Proof
Plane are electrostatic components for use with additional
equipment from the PASCO Electrostatics System
ES-9062B. The two charge producers are used to
generate equal positive and negative charges by contact.
The proof plane can be used to measure charge density
on a charged object.
The Charge Producers
The charge producers consist of two wands, one with
blue and one with white material attached to a conductive
disk. Briskly rub the blue and white surfaces of the two
charge producers together. The disk with the white
surface will acquire a positive charge; the disk with the
blue surface will acquire a negative charge. Rub the white
surface of the one charge producers against the proof
plane. The white disk will acquire a negative charge, while
the disk of the charge producers will acquire a positive
charge.
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Phone [phone] • FAX [phone] • web: www.pasco.com
10101 Foothills Blvd. • Roseville, CA 95747-7100
®
•Ifazerochargeisdesirable,dischargethechargeproducers
by touching the conductive disk and handle to ground. To be
sure the disk and handle is fully discharged, gently breathe
on the non conductive neck. The moisture from your breath
will help remove any stray charge.
•Avoidtouchingtheneckduringnormaluse.Theoils
from your hands will provide a path for charges to leak
off. Occasionally clean the disk surfaces and the neck
withalcohol.
•Whenyoufirstusethechargeproducers,orjustafter
cleaning, they may not produce charges readily. Rub the
white surface vigorously on the conductive disk of the
proof plane
➤ NOTE: The charge producers are designed
to be used with an electrometer (ES-9054B).
They do not produce sufficient charge for use
with a standard electroscope.
The Proof Plane
The proof plane is an aluminum-covered conductive disk
attached to an insulated handle. It is used to sample the
charge density on charged conductive surfaces.
blue surface
conductive disk
(black)
non-conductive
neck (white)
white surface
handle
➤ NOTE: Oil build-up on the non-conductive
neck can affect results. Clean with alcohol
before using.
conductive disk
(black)
non-conductive
neck (white)
aluminum surface
handle

Charge Producers and Proof Planes 012-07144A
2
➤ NOTE: You can then use an electrometer
and a Faraday ice pail (ES-9042A) to measure
the charge density on the proof plane, as
shown in the following illustration.
Other
The conductive disk material is carbon-filled black
polycarbonate (about 103Ω) with an aluminum disk.
The nonconductive neck is white polycarbonate (about
1014 Ω).
Limited Warranty
PASCO scientific warrants the product to be free from
defects in materials and workmanship for a period of one
year from the date of shipment to the customer. PASCO
will repair or replace, at its option, any part of the product
which is deemed to be defective in material or
workmanship. The warranty does not cover damage to
the product caused by abuse or improper use.
Determination of whether a product failure is the result of
a manufacturing defect or improper use by the customer
shall be made solely by PASCO scientific. Responsibility
for the return of equipment for warranty repair belongs to
the customer. Equipment must be properly packed to
prevent damage and shipped postage or freight prepaid.
(Damage caused by improper packing of the equipment
for return shipment will not be covered by the warranty.)
Shipping costs for returning the equipment after repair will
be paid by PASCO scientific.
Address: PASCO scientific
10101FoothillsBlvd.
Roseville, CA 95747-7100
Phone: [phone]
FAX: [phone]
email: [email protected]
web: www.pasco.com
By touching the proof plane to a surface, it will acquire
the same charge distribution as the surface. By measuring
the charge on the proof plane, the charge density on the
surface can be determined. The greater the charge on the
proof plane, the greater the charge density on the surface
where the proof plane made contact.
When the proof plane is touched to a conductor, the proof
plane becomes part of the conductive surface. If the
effect on the shape of the surface is significant, the
sampling of the charge density will not be accurate.
Therefore, always touch the proof plane to the conductor
in such a way as to minimize the distortion of the
conductive surface. The following illustration shows the
recommended method for using the proof plane to sample
the charge on a conductive sphere.
➤NOTE: To accurately sample charge density,
the conductor should be considerably larger than
the disk of the proof plane and have a relatively
large radius of curvature at the point from which
the sample is taken. However, the proof plane can
be used to test for charge polarity on conductors
of any shape.
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charged proof plane
in Faraday ice pail
signal lead
ground lead
Faraday ice pail and shield
charged conductive
sphere
Proof plane disk IS NOT
tangent to surface of
conductor.
Proof plane disk IS
tangent to surface of
conductor.
NO! YES!