tg protect

1. 20th
January 2004
Date: 10th
Jan 2004
Place: CPP Control Room
A meeting was called on to discuss regarding the restoration of Protections of
Turbines and Boilers. The following members were present during the meetings to
discuss about the above subject and concluded to restore the following
protections of turbines & Boilers with the values enclosed in a tabular form as
below, the same will be implemented by Automation on a case-to-case basis at
the earliest opportunity
For CPP For Automation
Sh.D.Bangabash Sh.H.P.Nanavati
Sh.G.G.Goud Sh.Ajay Verma
Sh.T.P.Krishnan
Sr.GM (Elect) was also present and gave clearance for generator protections
D.Bangbash
Cc
EP/JEP
Sr.GM (Elect)/DGM (Elect)
DGM (Auto)
All Member Present

2. Protection for TG-1 (24.5 MW)

3. Protection for TG-1 (10.5 MW)
Sr.No Particulars Alarm (Values) Trip (Values)
1 Turbine Front Shaft Vibration 120 microns 160 microns
2 Turbine Rear Shaft Vibration 120 microns 160 microns
3 Gear Box High Speed 120 microns 160 microns
4 Gear Box Low Speed 135 microns 180 microns
5 Generator Front 135 microns 180 microns
6 Generator Rear 135 microns 180 microns
7 Differential Expansion
1.2 mm
 -0.8 mm
1.2 mm
 -0.8 mm
8 Axial Shift
1.2 mm
 -0.8 mm
1.2 mm
 -0.8 mm
9 Hot Well Level Level Switch
10 Generator Trip Not Applicable
11 Extraction –1 Pressure 17 kg / cm² 22 kg / cm²
12 Extraction –2 Pressure 08 kg / cm² 11 kg / cm²
13 Turbine Speed High ≥ 5850 rpm ≥ 6050 rpm
14 Turbine Front Active Temp (Top) ≥ 100 ° C ≥ 120 ° C
15 Turbine Front Active Temp (Bot) ≥ 100 ° C ≥ 120 ° C
16 Turbine Front inactive Temp (Top) ≥ 100 ° C ≥ 120 ° C
17 Turbine Front Inactive Temp (Bot) ≥ 100 ° C ≥ 120 ° C
18 Turbine Front Journal Bearing ≥ 100 ° C ≥ 120 ° C
19 Turbine Rear Journal Bearing ≥ 100 ° C ≥ 120 ° C
20 Gear Box High Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
21 Gear Box Low Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
22 Gen Front Bearing Temp ≥ 100 ° C ≥ 120 ° C
23 Gen Rear Bearing Temp ≥ 100 ° C ≥ 120 ° C
24 Trip Oil Pressure ≤ 7.0 kg/cm ² ≤ 6.0 kg/cm ²
25 Lube Oil Pressure ≤ 1.2 kg/cm ² ≤ 0.8 kg/cm ²
26 Condenser Vacuum ≤ - 0.80 kg/cm ² ≤ - 0.5 kg/cm ²

4. Protection For TG- 2.85 MW
Sr.No Particulars Alarm (Values) Trip (Values)
1 Turbine Front Shaft Vibration ≥ 120 μ ≥ 160 μ
2 Turbine Rear Shaft Vibration ≥ 120 μ ≥ 160 μ
3 Gear Box High Speed ≥ 140 μ ≥ 180 μ
4 Gear Box Low Speed ≥ 140 μ ≥ 180 μ
5 Generator Front ≥ 140 μ ≥ 180 μ
6 Generator Rear ≥ 140 μ ≥ 180 μ
7 Differential Expansion
1.2 mm
 -0.8 mm
1.2 mm
 -0.8 mm
8 Axial Shift
> + 0.5 mm
< - 0.5 mm
> + 0.8 mm
< - 0.8 mm
9 Hot Well Level Level Switch
10 Generator Trip Not Applicable
11 Turbine Speed High > 5650 rpm ≥ 5850 rpm
12 Turbine Front Active Temp (Top) ≥ 100 ° C ≥ 120 ° C
13 Turbine Front Active Temp (Bot) ≥ 100 ° C ≥ 120 ° C
14 Turbine Front inactive Temp (Top) ≥ 100 ° C ≥ 120 ° C
15 Turbine Front Inactive Temp (Bot) ≥ 100 ° C ≥ 120 ° C
16 Turbine Front Journal Bearing ≥ 100 ° C ≥ 120 ° C
17 Turbine Rear Journal Bearing ≥ 100 ° C ≥ 120 ° C
18 Gear Box High Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
19 Gear Box Low Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
20 Gen Front Bearing Temp ≥ 100 ° C ≥ 120 ° C
21 Gen Rear Bearing Temp ≥ 100 ° C ≥ 120 ° C
22 Trip Oil Pressure ≤ 7.0 kg/cm ² ≤ 6.0 kg/cm ²
23 Lub Oil Pressure ≤ 1.2 kg/cm ² ≤ 0.8 kg/cm ²
24 Condenser Vacuum ≤ - 0.80 kg/cm ² ≤ - 0.5 kg/cm ²

5. Protection For TG- 12.5 MW
Sr.No Particulars Alarm (Values) Trip (Values)
01 Turbine Speed High > 6400 rpm ≥ 6600 rpm
02 Turbine Front Active Temp (Top) ≥ 100 ° C ≥ 120 ° C
03 Turbine Front Active Temp (Bot) ≥ 100 ° C ≥ 120 ° C
04 Turbine Front inactive Temp (Top) ≥ 100 ° C ≥ 120 ° C
05 Turbine Front Inactive Temp (Bot) ≥ 100 ° C ≥ 120 ° C
06 Turbine Front Journal Bearing ≥ 100 ° C ≥ 120 ° C
07 Turbine Rear Journal Bearing ≥ 100 ° C ≥ 120 ° C
08 Gear Box High Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
09 Gear Box Low Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
10 Gen Front Bearing Temp ≥ 90 ° C ≥ 120 ° C
11 Gen Rear Bearing Temp ≥ 90 ° C ≥ 120 ° C
12 Trip Oil Pressure ≤ 7.0 kg/cm ² ≤ 6.0 kg/cm ²
13 Lub Oil Pressure ≤ 1.2 kg/cm ² ≤ 0.8 kg/cm ²
14 Back Pressure ≥ 28 kg/cm ² ≥ 34 kg/cm ²

6. Sr.No Particulars Alarm (Values) Trip (Values)
1 Vacuum Pressure ≤ - 0.75 kg/cm ² ≤ - 0.5 kg/cm ²
2 Inlet Steam Temp Low ≤ 350 ° C ≤ 300 °
3 Hot well Level ≥ 70 % ≥ 90 %
4 Generator Trip Not Applicable
5 Turbine Front Active Temp (Top) ≥ 100 ° C ≥ 120 ° C
6 Turbine Front Active Temp (Bot) ≥ 100 ° C ≥ 120 ° C
7 Turbine Front inactive Temp (Top) ≥ 100 ° C ≥ 120 ° C
8 Turbine Front Inactive Temp (Bot) ≥ 100 ° C ≥ 120 ° C
09 Turbine Front Journal Bearing ≥ 100 ° C ≥ 120 ° C
10 Turbine Rear Journal Bearing ≥ 100 ° C ≥ 120 ° C
11 Gear Box High Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
12 Gear Box Low Speed Brg Temp ≥ 100 ° C ≥ 120 ° C
13 Gen Front Bearing Temp ≥ 95 ° C ≥ 120 ° C
14 Gen Rear Bearing Temp ≥ 95 ° C ≥ 120 ° C
15 Lube Oil Pressure ≤ 1.5 kg/cm ² ≤ 1.0 kg/cm ²
16 Turbine Over Speed ≥ 6600 rpm ≥ 7150 rpm

7. Boiler Protection (CFBC Boiler)
Sr.No Particulars Alarm Trip
1 Furnace Draft (Low) < -90 mmWC < -150 mm WC
2 Furnace Draft (High) ≥ +75 mmWC ≥+100 mm WC
3 Bed Temperature > 880 °C > 975 °C
4 Drum Level Low ≤ -150 mm ≤ -325 mm
5 Drum Level High ≥ +100 mm ≥+ 250 mm
Boiler Protection (AFBC Boiler)
Sr.No Particulars Alarm Trip
1 Furnace Draft (High) ≥ 6 mmWC ≥ 30 mm WC
2 Drum Level Low ≤ 35 % ≤ 25 %