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IS0
I N TE R NAT1 O N AL O R GAN I ZATl O N
FO R S TA N DAR D I Z AT I O N
1 S O R E C O M M E N D AT1 O N
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R 284
ELECTRICAL CONDUCTIVITY OF CONVEYOR BELTS
SPECIFICATION AND METHOD OF TEST
1st EDITION
November 1962
COPYRIGHT RESERVED
The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the national standards organization of that country, being
a member of ISO.
For each individual country the only valid standard is the national standard of that country.
Printed in Switzerland
Also issued in French and Russian. Copies to be obtained through the national standards organizations.
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BRIEF HISTORY
The IS0 Recommendation R 284, Electrical Conductivity of Conveyor Belts - Specijication
and Method of Test, was drawn up by Technical Committee ISO/TC 41, Pulleys and Belts (includ-
ing Vee-Belts), the Secretariat of which is held by the Association Française de Normalisation
(AFNOR).
Work on this question by the Technical Committee began in 1958 and led, in 1960, to the
adoption of a Draft IS0 Recommendation.
In March 1961, this Draft IS0 Recommendation (No. 443) was circulated to all the IS0
Member Bodies for enquiry. It was approved by the following Member Bodies:
Australia France New Zealand
Austria Germany Portugal
Spain
Belgium Greece
Brazil India Sweden
Chile Iran Turkey
Colombia Israel United Kingdom
Czechoslovakia Italy U.S.A.
Denmark Mexico U.S.S.R.
Yugoslavia
No Member Body opposed the approval of the Draft.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0 Coun-
cil, which decided, in November 1962, to accept it as an IS0 RECOMMENDATION.
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0
ISOIR 284 - 1962 (E)
IS0 Recommendation R 284 November 1962
ELECTRICAL CONDUCTIVITY OF CONVEYOR BELTS
SPECIFICATION AND METHOD OF TEST
1. SCOPE
The purpose of this IS0 Recommendation is to specify the maximum electrical resistance of a
conveyor belt and the corresponding method of measurement.
off charges of electri-
The test is intended to ensure that the belt is sufficiently conductive to drain
city which may form on it in service.
2. SPECIFICATION
The electrical resistance should not exceed 3 x 108 ohms (300 megohms).
3. METHOD OF TEST
3.1 Principle
An electrical current of specified voltage is passed through electrodes of a suitably prepared
test piece taken from the belt.
3.2 Apparatus
The apparatus consists of the following:
3.2.1 Sheet of insulating material a little larger than the test piece.
3.2.2 Two cylindrical and coaxial brass electrodes, the base of one being circular and the other
annular. The dimensions and masses are given in Figure 2. The bases of these electrodes
should be machined flat and polished. A flexible insulated wire is connected to each
electrode.
3.2.3 Resistance-measuring instrument capable of giving readings between IO5 and 1010 ohms
to F within 5 per cent.
3.2.4 Source of direct current at loo0 V maximum.
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Minimum moss
115 g
Minimum moss 900 g
Polyeth ylene
glycol
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5 in (125 mm)
I
6 in (150 mm) 6 in (150 mrn)
I
FIG. 2. - Electrodes
FIG. 1. - Design to be painted on the test piece
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