Hermetically Sealed Type Transformer with Buchholz Relay
Hermetically Sealed Type Transformer with Buchholz Relay
(OP)
I need your advices on the subject.
As I know, buchholz relay is generally required for protection of conservator type transformer.
However, the client spec. requires buchholz relay for hermetically sealed type transformer as well.
I wonder whether it is excessive requirement or not.
If a buchholz relay cannot be applied to hermetically sealed type transformer, then could you please give me some tips how to persuade my client?
Thanks in advance.
As I know, buchholz relay is generally required for protection of conservator type transformer.
However, the client spec. requires buchholz relay for hermetically sealed type transformer as well.
I wonder whether it is excessive requirement or not.
If a buchholz relay cannot be applied to hermetically sealed type transformer, then could you please give me some tips how to persuade my client?
Thanks in advance.






RE: Hermetically Sealed Type Transformer with Buchholz Relay
RE: Hermetically Sealed Type Transformer with Buchholz Relay
See site
http://www.indubras.com.br/ingles/produto10.htm
Compare
"Sudden Pressure Relay",
"Gas Detector Buchholz Relay", and
"Gas Detector Relay".
If you have an oil expansion tank, you may consider a Buchholz relay.
If there is no oil expansion tank, a buchholz relay is not appropriate.
If the transformer is sealed with a gas space above the oil level consider the "Sudden Pressure Relay" that davidbeach suggests.
One of the functions of a buchholz is to detect sudden or rapid flow of oil into the conservator or oil expansion tank. If you do not have a conservator it will be challenging to install a buchholz. If you do succeed in installing it, (with a blanking flange on the conservator side, for example) it may not function.
A sudden pressure relay responds to sudden pressure.
A buchholz relay responds to sudden flow, and from that it infers sudden pressure.
I assume that your hermetically sealed transformer has a gas charge above the oil level. This will defeat the "Gas Detector" feature of the buchholz.
respectfully