AUTO TRANSFORMER 86LOR TRIP ARRANGEMENT

The Transformer protection tripping can grouped as follows

1. SET-1 Main Protection

The main protection can be divided in to two groups (CB TC-1 Tripping)

a. LOR 86-1 ( Neumarical relays protection)
1.Differential protection (86T)
2.REF protection (87 REF)
3.HV side Over Flux protection (24 - HV/T)
b. LOR 86-3 ( Mechanical protection)
1.Buchhloz Relay trip - Main tank (63 T)
2.WindingTemp High Trip - Serious Winding Main Tank (49 W-TS)
3.Winding Temp High Trip - Common Winding Main Tank ( 49W-TC)
4.Winding Temp High Trip - Tertiary Winding ( 49 W-TT)
5.Buchhloz Relay trip - OLTC (62-OLTC)
6.Buchhloz Relay Trip - Grounding Transformer (63- GT)

2. SET-2 Back up Protection

The back up protection can be divided in to two groups (CB TC-2 Tripping)

a. LOR 86-2 ( Numerical relays protection)

1.HV & MV side backup 3 phase & ground fault inverse time & inst O/C
relay unit and function (67HV & 67NHV and 67MV & 67NMV)
2.HV side Over Flux protection (24 - HV/T)
3. Neutral backup O/C relay ( 51 G-T)
4.Tertiary winding O/C relay ( 51TW/HS & 51 TW/LS)

b. LOR 86-4 ( Mechanical protection)

1.Pressure Relief - trip-main tank (63PR-T)
2.Oil Tem very high trip - main tank ( 26-T)
3.Oil Tem very high trip OLTC ( If any) (26- OLTC)
4.Pressure relief OLTC tank - (63-OLTC)
5.Oil pressure relay Main tank (63-T)
6.Pressure relief Trip grounding transformer ( 63 - PR-GT)

TEST FORMATS

1. AUX RELAY

2.MAIN RELAY

3.EQUIPMENTS

TRANSFORMER OIL LEVEL vs TEMPERATURE CURVE

This comman for all Power Transformers

RELAY SOFTWARES USED IN SUB-3

1. RED 670 - LINE PRO - ABB
PCM 600 - 2.3
2. RET 670 - TR PRO - ABB
PCM 600 - 2.3
3. REB 500 - BB PRO - ABB
REB WIN - 7.5
4 . 7SS52 - BB PRO- SIEMENS
DIGSI - 4.83
5.MICOM - AREVA
MICOM S1 STUDIO - 3.4
6. SEL METER - ENERGY METER - SEL
SEL SOFTWARE

AUTO RECLOSE

Consider a station (1 1/2 schemes ) feeds with two lines
1. Line -1 dead for maintenance work
2.In Line -2 there is a Zone -1 fault
Now The Auto reclose should block because already one Line -1 is out and may be fault exist in Line -2 now the condition is station totally dead. So the station should not energized by Line-2 Auto reclose with fault line.
If the Power Transformer connected with same cross bay then it should be energized with Bus voltage. If Bus side Transformer CB in open condition then the A/R operation should block for the line.Otherwise the Transformer also energized with fault line.