EN 50216-2-2002 pdf download.Power transformer and reactor fittings Part 2: Gas and oil actuated relay for liquid immersed transformers and reactors with conservator.
Other values may be agreed between purchaser and supplier.
The relay shall be insensitive to oil flow from conservator to tank.
The relay shall be insensitive to the oil flow generated when the transformer is submitted to an external short circuit.
The relay shall operate within 0,5 s.
5.2 Oil loss from tank
The alarm element shall operate if the oil level in the relay drops by the same volume as for gas collection.
Further oil loss shall cause the trip element to operate before the relay pipework is free of oil.
5.3 Latching of trip element
By agreement between purchaser and supplier, a device can be provided which holds the trip element in the position after an oil flow operation until it is reset.
6 Electrical characteristics of switch
This device is based on EN 60947-5-1.
6.1 Switch type
The purchaser shall specify whether the switch shall have normally open, normally closed or change over contacts (normally means the relay filled with oil and without any fault on the protected equipment).
6.2 Rated currents
The rated current shall be 2 A r.m.s. and the short time current 10 A r.m.s. for 30 ms. Other values may be agreed between purchaser and supplier.
6.3 Breaking and making capacity
Other values may be agreed between purchaser and supplier.
The minimum contact life shall be 1 000 operations.
The switch shall also be able to make a low current down to 10 mA for any value of voltage
defined in Table 6 even after one year of non-operation.
7 Mechanical requirements
7.1 Terminal box
A terminal box shall be provided with a minimum of four terminals and one earth terminal. The terminals shall be designed to accept cables having a cross sectional area of between 1,5 mm2 to 4 mm2. The thread shall be minimum M5.
It shall be possible to fit two cable glands on the connection box.
The thread for the cable glands should be either Pg 16 or M20 x 1,5 (to be agreed between supplier and purchaser).
A minimum of one cable gland and a threaded hole for mounting the second cable gland shall be provided unless otherwise agreed.
The marking in the terminal box shall comply with that on the connection diagram.
7.2 Testing facility
The relay shall be provided with a device to check the operation of alarm and trip contacts independently (without damaging the contacts or their operating mechanism).
7.3 Gas sampling
The relay shall be fitted with a gas sampling petcock.
A facility shall be provided for the connection of a 3,17 mm (1/8”) tube for sampling at ground level,
7.4 Draining device
A draining device shall be provided.
If required, a provision shall be allowed to permit draining at ground level.
7.5 Presence of gas in the relay
It shall be possible to visually check the presence of any gas in the relay from both sides. If required, the sight glass shall be calibrated to indicate the volume of gas collected.
7.6 Mounting arrangement
An arrow on the relay shall indicate the oil flow direction from the transformer tank to the conservator.
7.7 Pressure and vacuum
The relay shall withstand all pressure and vacuum test stresses (see 9.1.1 and 9.2).
EN 50216-2:2002 —10—
8 Nameplate
The nameplate shall contain the following information:
– name of supplier;
number of this standard and year of edition;
– type of relay;
— connection diagram (it may be incorporated on the nameplate or included in the terminal box);
— state of contacts: normally open, normally closed or change over contacts; seismic withstand class.
The type of relay shall allow identification of the relay characteristics from the mounting, operating and maintenance manual supplied by the supplier.EN 50216-2-2002 pdf download.