OPERA
T
OR’S HANDBOOK
Health and Safety at Work and
Electricity at Work Regulations 1989
The above regulations state that all electrical equipment should be regularly checked for safety.
It is recommended that the machine should be regularly checked by the person, or people,
responsible for daily maintenance and use, by switching off and disconnecting the plug and
checking the general condition of the machine, paying particular attention to the mains electrical
lead and plug.
Formal Checks
Similar checks to those above should be carried out in a more formal and systematic manner by
a competent person appointed by the duty holder (employer). The period between checks should
be decided by the duty holder and will vary considerably depending on conditions of use and the
local environment.
These tests should be expanded to include the following tests, using a suitable electrical appliance
tester used in accordance with the manufacturer’s instructions:
For guidance: We recommend that the machine is tested at least once a year, but more regularly
if local conditions demand.
1.
Earth Bond Test:
A current of 25 amps from an a.c. source, having a no-load voltage not
exceeding 12 volts, is passed between the earth terminal or contact and accessible metal
parts, the resistance must not be greater than 0.1 ohms, excluding the mains lead.
2.
500 volt d.c. Insulation Test:
The resistance must not be less than 2M ohms.
Should either test fail, please contact our Service Department.
Do not reconnect the machine.
Note:
Flash testing at 1250 volts is not recommended on this equipment because:
(a) The equipment is fitted with electrical filtration devices and/or electronic components.
(b) It is not necessary to flash test to ensure safety - the earth bond and insulation tests are
sufficient.
(c) Repeated flash testing can damage electrical insulation.
Further guidance can be obtained in the following publication:
Maintaining Portable and Transportable Electrical Equipment
HS (G) 107 HSE 1994 ISBN 0 7176 0715 1
Available from HSE Books, P.O. Box 1999, Sudbury, Suffolk. CO10 6FS
Telephone: 01787 881165 Fax: 01787 313995
This information is current at 1/2002. Source: Health and Safety Executive
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