This document discusses protection relays used at Tondgooyan Petrochemical Co. in Mahshar, Iran. It provides characteristics of protection relays including measuring current, voltage, frequency and other parameters. It examines effects like thermal and insulation performance. The document outlines the power grid and industrial plant configuration, and covers topics like overcurrent, over/under voltage, over/under frequency protection functions. It provides information on different Sepam relay types for various applications and protection zones.

1. Sepam
Protection
Relays
Tondgooyan Petrochemical Co.
Mahshar, Iran
By: Ahmad Mokhtari Laleh
21‐24 July 2018
www.imSepehr.com

2. Characteristics:
1.Current
2.Voltage
3.Frequency
4.Other Parameters
Effects:
1.Thermal
2.Insulation
3.Performance
Rated
Quality

3. 33kV
6kV6kV
0.4kV0.4kV
33kV
Power
Grid(132kV)
Power
Grid(132kV)
DG
0.4kV-0.23kV
Industrial
Plants

4. Time
X
Unlimited
Limited time
Minimum time
Rated
0
Time
X
Rated
0
Overcurrent
Over/under voltage
Over/under Frequency
1.Current
2.Voltage
3.Frequency
1 2

5. Time
X
Rated
0
X
t
0
A B
C D
E F
A
B
C
D
E
F
1 2
t1 t2

6. Time
X
Rated
0
X
t
0
A
B
C D
E
F
A
B
C
D
E
F

7. X
t
0
X
t
t=f(x)

8. Protection
Function
• t (time)
– Fixed
– Variable
• X (inputs)
– Measured
– Calculated
• f (function)
– Individual stage or Multi-stage
t
x
t=f(x)

9. t
I
Is2Is1 Is3
Variable
Fixed
f1
f2
f3
Fixed
Protection function: multi-stage
t=f(x)X t
Settings









IIsf
IsIIsf
IsIIsf
t
33
322
211
t3
t2

10. Sepam Relay types
Series 10
simple applications
Series 20
usual applications
Series 40
demanding applications
Series 80
custom applications
S: SUBSTION
B: BUSBAR
T: TRANSFORMER
M: MOTOR
G: GENARATOR
C: CAPACITOR

11. 1. Title bar
2. Menu bar
3. Toolbar
4. Work zone
5. Status bar

12. SFT2841
1. General settings
2. Protections
3. Operation

13. Protection Functions
Current
Voltage
Frequency
Voltage & Current
Voltage & Frequency
Others

14. R
S
T
Bolted

15. R
S
T
Arc flash

16. Bolted (LLL, LL, LLG, LG)
In=2.8 kA
LLL = 50 kA
LL = 44 kA
LLG= 45 kA
LG = 50 kA
6kV
0.4kV
33kV
In=1 kA
LLL = 12 kA
LL = 10.5 kA
LLG= 10.6 kA
LG = 0.2 kA
In=1.2 kA
LLL = 13 kA
LL = 11 kA
LLG= 11 kA
LG = 0 k A
70 MVA
10 MVA
2 MVA

17. Phase Overcurrent Protection
1. Description
2. Block Diagram
3. Setting groups
4. Setting Modes
5. Type 1, 1.2
6. IDMT tail
7. Harmonic 2 Restraint
8. Timer Hold
9. Tripping
Characteristics
10.Tripping confirmed by
other function
11.Protection Zone

18. Time
Current
Is=1000
100 msec.
Is=1000A, DT=100 msec.
100 msec.+70msec.
DT=100
msec.
Timer
Time
Time
Time
Pickup
Signal
Trip
Output

19. 4- Setting Modes
10I/Is settings
TMS
TMS
I
I
k
t
S
S 


1)( 

T
I
I
k
t
S
S 


1)(

20. 9-1 Drop-out/Pick-up ratio
To improve stability, the functions have a drop
out/pick up ratio d that is a % of the threshold
setting.

22. Time
X
Rated
0
X
t
0
I1, I3
I1,
I3
I2
I1
I2
I3
I2

23. LG Fault
∑R2
R1
R3
∑

24. 10-Protection Zone
I0>
I0>
Is0
Is0
I0>
I’s0
I’s0

25. 2- Residual component sensitive
to single-phase faults IR0
•Outside zone: IR0= LG
•Inside zone: IR0 = LG/2

26. V1
V2V3
V1
V2V3
V0 V1
V2V3
V0
3210 VVVV 

27. V1
V2V3
V1
V2V3
V0
V2V3
V0
3210 VVVV 

28. Current Protection (8)
Current
Overcurrent
Earth Fault
Phase undercurrent
Negative sequence / unbalance
Excessive starting time, locked rotor
Thermal overload
Breaker failure
Starts per hour

29. Machine heat rise @ Ta=50oC, full load
in different Overloads (%10, %20, %30, %40)
Hour
Ti
oC
120
130
140
150
160
170
180
190
3.8 4 4.2 4.4 4.6 4.8 5