background image

xx02000677.jpg

RARIC
Shaft current protection

• Sensitive protection for bearings of large rotating machines

• Operates for shaft currents larger than 0,3 - 0,8 A AC, depend-

ing on the diameter of the shaft

• Fundamental or third harmonic operating principle

• AC or DC powered, galvanically isolated

• Shaft current transformer with test winding

• Can be applied to shafts with diameters up to 2960 mm

• Settable time delay

• Trip relay with heavy duty contacts and indicating flag

• Test switch

Features

User’s guide

1MRK 502 001-UEN

Revision: A

Issued January 2003

Data subject to change
without notice

Summary of Contents for RARIC

Page 1: ...the shaft Fundamental or third harmonic operating principle AC or DC powered galvanically isolated Shaft current transformer with test winding Can be applied to shafts with diameters up to 2960 mm Settable time delay Trip relay with heavy duty contacts and indicating flag Test switch Features User s guide 1MRK 502 001 UEN Revision A Issued January 2003 Data subject to change without notice ...

Page 2: ...current transformer 5 3 MODE OF OPERATION 6 4 RECEIVING STORAGE AND INSTALLATION 8 4 1 Receiving 8 4 2 Storage 8 4 3 Installation 8 5 SETTING TESTING AND COMMISSIONING 9 5 1 Setting 9 5 2 Testing and commissioning 9 5 2 1 Injection test 9 5 2 2 Primary test 9 6 MAINTENANCE 9 7 TECHNICAL DATA 10 8 DIAGRAMS 12 9 DIMENSION ILDD 15 10 MOUNTING 16 ...

Page 3: ...bearing and the ground structure a breakdown of the oil film insulation may give rise to a heavy current which leads to destruction of the bearing Consequently the bearing pedestal furthest from the prime mover is usu ally insulated from ground and the insulation should be supervised by a suitable protection Severe damage on the bearings is not expected to occur if the shaft current is less than o...

Page 4: ... 4 only for RARIC Version 2 contains capacitors reactors and resistors One parallel resonance and one series resonance circuit in the filter gives the frequency char acteristic shown in Fig 4 3 Overcurrent relay RXIK1 is the measuring unit of RARIC The operating value of RXIK 1 is steplessly settable 0 5 2 mA The current input circuit has an resist ance of 82 ohms and contains an RC circuit to sup...

Page 5: ...s split up in two parts for sizes with inner diameter up to and including 2 000 mm For larger diameters the transformer is split up in four parts When the parts are jointed the steel sheets of the core are interleaved with an overlap of about 30 mm The measuring winding with 400 800 turns depending on the diameter of the transformer is evenly distributed on the parts of the core When the transform...

Page 6: ...e oil film in the bearing pulses are fed to RXIK 1 If these pulses exceed the operating value of the relay and the intervals between the pulses are shorter than 0 9 s the contacts of the out put relay will be continuously closed The impedance of the current measuring circuit in RXIK 1 is about 80 ohms Hence for Version 1 the operate voltage is about 40 mV at the low est setting 0 5 mA of RXIK 1 Fi...

Page 7: ...g 0 5 resp 1 mA as func tion of the inner diameter of ILDD The filter in Version 2 rejects the fundamental voltage by more than 70 1 Fig 4 Operate voltage of RARIC Version 2 as function of frequency Rated frequency 50 Hz 502001 1 7 6 1 0 5 0 1 0 04 V 30 50 100 150 500 I 1 mA s I 0 5 mA s f Hz 502001 2 ...

Page 8: ... the bearing is flowing in the shaft This means that it should be mounted at the rotor side of any bearing or slip ring To avoid disturbances the transformer shall be mounted on the turbine side of the machine which is free from field bars and at maximum distance from the end of the stator winding See Fig 12 and Fig 13 for recommended mounting Screened cable with twisted pairs and with the screen ...

Page 9: ...hen 3 V rated frequency voltage is applied to relay terminals 107 231 241 see Fig 4 Without altering the settings interchange the leads to the test terminals and check the operate value It can be different from the earlier measured value Both values should be recorded for comparison at future tests Set the injection current to 2 times the operate value and check the time delay Connect a brush via ...

Page 10: ...m aux voltage AC supply DC supply Approx 2 VA before and 8 VA after operation Approx 3 W before and 7 W after operation Time setting range RXKL 30 ms 99 h Permissible ambient temperature 5 to 55 C Permissible range auxiliary voltage supply 80 110 of rated voltage Table 2 Electromagnetic compability tests Power frequency test SS 436 15 03 0 5 kV class PL4 Fast transient test SS 436 15 03 4 8 kV cla...

Page 11: ... for 1 s 5 4 A continuously Making and conducting capacity L R 10 ms 30 20 A for 200 ms 10 10 A for 1 s Breaking capacity dc L R 40 ms 2 1 5 A at 24 V 1 0 5 A at 48 V 0 4 0 2 A at 110 V 0 2 0 1 A at 220 V 7DEOH Weights and dimensions Weight RARIC version 1 RARIC version 2 ILDD 4 kg 5 kg 10 80 D 300 2300 kg where D is the inner diameter in mm Dimension RARIC version 1 RARIC version 2 ILDD 4U 24C 4U...

Page 12: ...C converter RXTUG 22H 8 DIAGRAMS 7429010 AD 31 18 22 I 28 41 21 4B 4A 16A 16B 1A 1B 18A 18B I U 126 127 128 118 116 117 11B 11A 10B 10A 9B 9A 12B 12A 313 21 11 24 250V I I 1 2 101 107 113 119 313 RTXP 18 RXTUG 22H RXIK 1 RXKL 1 RXME 18 1 TRIPPING OF CB S ETC 2 ALARM ETC 24C 4S 3 3 LOSS OF EL 17A 17B 17 27 101 16 26 316 318 317 25 27 26 16 14 15 15 17 13 11 12 16 119 21 11 107 101 2A 2B 113 3B 3A 1...

Page 13: ... Ver sion 2 with AC DC converter RXTUB 2 Fig 8 Terminal diagram 7429 010 ADA for RARIC RK 649 101 AD Version 1 7429010 FC S1 S2 A B I TRIPPING ETC ALARM ETC 220V 110V SHAFT CURRENT PROTECTION 100V 0V RARIC 16A 113 25 101 1A 18A 3B 101 4B 4A 3A 101 107 16 2A 319 26 17A 107 31 107 41 101 12A 11A 10A 9A 7429 010 ADA ...

Page 14: ... I TRIPPING ETC ALARM ETC LOSS OF EL 24 250V SHAFT CURRENT PROTECTION RARIC 16A 119 25 107 316 107 318 107 317 101 1A 18A 107 116 107 118 3B 101 4B 4A 3A 101 113 16 2A 313 26 17A 113 31 113 41 101 U 7429 010 BAA S1 S2 A B TRIPPING ETC ALARM ETC 220V 110V 100V 0V RARIC 16A 125 25 101 1A 18A 3B 101 4B 4A 3A 101 119 16 2A 331 26 17A 107 231 107 241 101 12A 11A 10A 9A I 7429 010 FCA I SHAFT CURRENT PR...

Page 15: ...halves are interconnected via the termi nals S All dimensions are in mm Transformer with D 2000 mm has the cross section dimensions accord ing to Alt 1 Transformer with D 2000 mm is split up in four parts and has the cross section according to Alt 2 9 DIMENSION ILDD Max 70 38 50 Alt 1 42 65 Max 85 Alt 2 D 5 AQ Trafo AB B A S2 S1 S en02000669 vsd S ...

Page 16: ...dro generators Fig 13 Recommended mounting of the shaft current transformer ILDD on turbo generators 10 MOUNTING RARIC Oil film Bearing housing Insulation Rotor Turbine Shaft current transformer ILDD en03000001 vsd RARIC Generator Turbine Earthing Shaft current transformer ILDD Insulation Bearing Oil film Bearing en03000002 vsd ...

Page 17: ...ld be mounted with 4 supports One of the alterna tives 1 2 or 3 can normally be used Except the supporting bar all details are the same for all alternatives Site weldings indicated for alternative 1 applies to all alternatives Fig 14 Examples of mounting supports en03000004 tif ...

Reviews: