10
Preparations for use
Getting started
It is important to read the user guide thoroughly before operating the Oil Test Sets for the first time.
The safety
warnings are particularly important.
Supply voltage
Before connecting line power to the instrument, the ground connector should be connected to a suitable earth point.
Both the AF and PB models are designed to operate on 50/60 Hz AC line power in the range 90 to 265 V AC.
For PB models, a 12 V DC power circuit for battery charging is fitted when either NiMH or lead acid battery packs are
ordered. The battery can be either charged using the supply 12 V vehicle charger cable or from mains power.
Assembly
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Unpack instrument and contents of the packing box.
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Ensure that the instrument is placed on a solid surface or table with sufficient working space.
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Connect ground to a suitable earth connector.
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Fit selected electrodes to the threaded shafts in the test vessel taking care not to scratch electrode surfaces.
Electrodes should be hand tightened onto the shafts to prevent any movement during use.
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Adjustment of the electrode gap should be done with the feeler gauges provided, adjustment wheels locked and
the gap rechecked.
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Fit test vessel into instrument chamber.
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If batteries are fitted, before switching on the instrument for the first time, connect power and leave for a period
of at least four hours. This will ensure a full charge of the battery. (PB models only)
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Read the section in this document entitled, “Instrument Operation” before powering up the Oil Test Sets for the
first time.
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Connect line power.
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Turn on the instrument.
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Follow the instrument setup procedure detailed below.
Test Vessel Preparation
1. Storing and subsequent cleaning
IEC 60156 recommends that a separate test vessel assembly is used for each type of
insulating fluid that it is to be tested. The standard requires that the test vessels are
filled with dry insulating fluid of the appropriate type, then covered and stored in a dry
place.
ASTM offers an alternative option of storing the vessels empty in dust-free cabinet.
Immediately prior to testing, vessels stored full of oil must be drained and all internal
surfaces, including the electrodes, rinsed with fluid taken from the sample to be tested.
The vessel should then be drained again, and carefully filled with the test sample,
taking particular care to avoid the formation of bubbles. If the vessel was stored empty,
or if it is to be used for a different type of fluid from that with which it was filled during storage, it should be cleaned
with an appropriate solvent before rinsing and filling.
ASTM D1816 specifies the use of a dry hydrocarbon solvent such as kerosene, which meets the requirements of D235.
Solvents with a low boiling point should not be used as these evaporate rapidly, cooling the vessel and giving rise to the
risk of condensation. Solvents commonly used include acetone and, in the USA, toluene. Toluene is banned in Europe.
Use lint-free clean-room wipes to clean the vessel. Do not use paper towels as they may introduce particles that hold
