1 Scope
This standard specifies the terms and definitions, product designation and basic dimensions, technical requirements, test items and methods, marking, packaging, transportation and storage of buchholz relays for oil-immersed transformers.
This standard is applicable to the buchholz relays for all oil-immersed transformers with oil storage tanks and oil-immersed on-load tap-changers (hereinafter referred to as relays).
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 191 Packaging — Pictorial Marking for Handling of Goods
GB/T 2900.15 Electrotechnical Terminology — Transformer, Instrument Transformer, Voltage Regulator and Reactor
GB 4208 Degrees of Protection Provided by Enclosure (IP Code)
JB/T 8448.1 Technical Specifications of Sealing Articles for Transformer and Similar Products — Part 1: Rubber Sealing Articles
3 Terms and Definitions
For the purpose of this document, the terms and definitions given in GB/T 2900.15 and the following apply.
3.1
buchholz relay
relay protection device for oil-immersed transformers
Note: When the oil is decomposed to generate gas or cause oil flow impulse due to internal failure of the transformer, the contact of the relay is actuated to turn on the specified control loop, and the signal is sent in time or the transformer is automatically cut off.
3.2
alarm contact
electrical contact inside the relay that operates when the amount of gas accumulated inside the relay reaches the specified range
3.3
trip contact
electrical contact inside the relay that operates when the flow rate of the transformer oil flowing through the relay reaches a specified setting
Foreword I
1 Scope
2 Normative References
3 Terms and Definitions
4 Product Designation and Basic Dimensions
4.1 Product designation
4.2 Basic dimensions
5 Technical Requirements
6 Test Items and Methods
6.1 Routine test
6.2 Type test
6.3 Test methods
7 Marking, Packaging, Transportation and Storage
Figure 1 Basic Dimensions of the Relays with 25 mm Pipe Diameter
Figure 2 Basic Dimensions of the Relays with 50 mm and 80 mm Pipe Diameter
Table 1 Basic Dimensions of Relays with 50 mm and 80 mm Pipe Diameter
Table 2 Operating Parameters of Relay Contacts
Table 3 Oil flow rate in relays
Table 4 Power Frequency Test Voltage
Table 5 Pressure Test Conditions