Megger OTS 60AF/2, User Manual

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The OTS60AF/2, OTS80AF/2 and OTS100AF/2 are used for determining the dielectric strength of liquid
insulants, such as the insulating oils used in transformers, switchgear and other electrical apparatus.
They are transportable and suitable for laboratory use as well as testing on site. A four wheeled trolley is
available to assist with on-site transportation.
The test sets are fully automatic. The operator has simply to prepare the test vessel, load it with sample
oil, place it in the test chamber, select the appropriate specification for the tests and then start the test
sequence. The test set carries out automatically (and if necessary unattended) the sequence of tests as
defined by the pre-selected national specification.
Oil testing specifications, for which the sets are pre-programmed, are as follows:-
International IEC 156 1995
British BS 5874:1980, BS148:1984,
BS 5730a:1979
American ASTM 1816-84a, ASTM D877
German VDE 0370/84
French NFC 27-22:1974
Italian CEI 10-1-1987
Spanish UNE21-309-89
Russian
Γ
OCT 658-75
Rumanian STAS 286-81
South African SABS 555-1985
Australian AS 1767-1976
Institute of Petroleum IP 295/83
European EN60156 (1996)
For other specifications, five separate, fully programmable, custom test sequences are available which
can be stored within the non volatile memory (NOVRAM). A 5 minute test sequence is also provided so
that a user may quickly obtain an idea of the state of an oil sample.
Three types of withstand (proof) testing of an oil sample are available. The principle of these tests is to
subject the oil sample to a specified voltage for a defined length of time (1 minute) to see if it will
withstand that voltage. Withstand test ‘A’ and Withstand test ‘B’ incorporate a user definable initial stand
time period.
Safety features incorporated in the design include the safety interlock on the test chamber cover and an
easily operated mains supply On/Off switch. These ensure a high level of safety for operators, provided
the set is used in a responsible manner.
Applications
6
Power cord
If the power cord plug is not suitable for your type of socket outlets (receptacles), do not use an
adaptor. You should use a suitable alternative power cord, or if necessary change the plug by cutting
the cord and fitting a suitable plug. The colour code of the cord is:
Earth (Ground) Yellow/Green
Neutral Blue
Phase (Line) Brown
If using a fused plug, a 13 Amp fuse to BS 1362 should be fitted.
Note: A plug severed from the power cord should be destroyed, as a plug with bare conductors is
hazardous in a live socket outlet (receptacle).