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Insulating oil passivator concentrate is supplied in bulk (by road tanker), 205 litre steel drums or 25 litre plastic containers.

What does it do?

EOS® PASS is supplied as a 10% concentrate usually in 25 litre containers and should be added to the transformer main tank along with EOS® HIB inhibitor. You must use both additives because adding a passivator alone can cause stray gassing and disrupt dissolved gas analysis monitoring.


Things to remember

Please note that these specialist transformer additives will only be supplied by EOS as part of a package that includes a Mobile Processing Unit and specialist field service operators

In recent years there has been much concern and discussion regarding corrosive sulphur formation in modern generation, highly refined unused insulating oil.

EOS recommends that you sample and test your oil in critical transformers for potential corrosive sulphur and DBDS. Once you have results then you can make an informed and sensible decision on the next step.

Depending on your risk assessment possible options are:

1. Increase cooling and monitor

2. Add EOS® PASS and EOS® HIB

3. Oil replacement – drain, flush, drain and refill via mobile processing unit

4. Mobile Regeneration to remove DBDS (Di-Benzyl Di-Sulphide)

Electrical Oil Services has gained quite a bit of experience adding EOS® PASS and EOS® HIB to a variety of transformers from grid to generator transformers and would be happy to advise you. For a detailed discussion and assessment of the options open to you please Contact Us.


Safety Data Sheet

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