OVERCURRENT PROTECTION RELAYS
CKR Series
CKR-81T-96 (96x96mm)
CKR-93T (144x144mm)
t (sec.)
Current-Time Characteristics
I1 = (t)
R1
Power
source
I2 = (t)
R2
I3 = (t)
R3
I4 (t) < I3 (t) < I2 (t) < I1 (t)
I4 = (t)
Functions
Single-phase protection
Two-phase protection
Three-phase protection
Earth fault protection
Time and current setting
Overcurrent pick-up
I>
Overcurrent instant
I>>
0.2 - 3.35 x In, Step 0.25
2 - 17 x (I>), Step 1
Definite time
2.5, 5, 15 sec. 0.1-1 Step 0.1
Inverse time
According IEC255, ANSI
(normal, very, extremely, longtime, moderately)
CKR-9XT series don't have moderately inverse time.
Time multiplier for curves
0.1-1, Step 0.1
Parameters
Électriques
Electrical Parameters
R4
I1 (t)-R1
I2 (t)-R2
I3 (t)-R3
I4 (t)-R4
Energy flow
direction
1
10
20
24 V DC,
Operating Voltage(Un)
IA / I
A. CKR- 9XX series have the following I/t characteristics.
According to IEC-255, BS-142 these are:
a - Normal Inverse
b - Very Inverse
c - Extremely Inverse
d - Long Time Inverse
e - Independent Time 1 (2.5 sec.)
f - Independent Time 2 ( 5 sec.)
g - Independent Time 3 (10 sec.)
h - Independent Time 4 (15 sec.)
The instantaneous tripping current, the time multiplication
factor, and current-time characteristics adjustments both
for the phases and neutral can be selected separately.
220 V DC
24 V DC,
230VAC±10%
85-265 V AC / DC ±10%
50/60 Hz
50/60 Hz
Operating Current(In)
Power Consumption
Burden
1 A (earth), 5 A (phase)
< 2 VA
< 3 VA
1 C/O for earth
1 C/O for phase
(8 A, 2000 VA, resistive)
Relay output
Current 5% In or Iset;
Time 7,5% or ±40 msec.
Accuracy
Parameters
Mécaniques
Mechanical Parameters
Non-flammable enclosure
Double Insulation (
),
Measurement Category III
Terminal Connection
Flush mounting with rear
terminals
31
CKR SERIES
IP40 (front panel)
IEC 60255-3
IEC 60255-6
IEC 529
CKS SERIES
IP51 (front panel)
IEC 60255-3
IEC 60255-6
IEC 60870-5
IEC 60529
CKR-93T
CKR-92T
SPECIFICATIONS
CKR-91T
Microcontroller based CKR series overcurrent relays
combine both inverse time and independent time relays
in one unit. These relays are used for protecting
transformers, motors, generators, and power lines
in energy distribution systems against short circuits and
grounding faults.
The most important point to achieve the uppermost
protection is to apply “selective protection”. The main
purpose of selective protection is locating and
disconnecting the faulty circuit from the network as soon
as possible but leaving the rest of the network active.
The accurate protection by the inverse-time overcurrent
relays can be accomplished with the following conditions :
1) Relays having the same operation characteristics
should be used in series with each other.
2) Tripping intervals of the relays used within the system
must be adjusted in the form of “current/time steps”.
Current dependent tripping-time adjustment of the relays
should be done in such a way that the “current/time steps”
should be reduced as getting away from the source.
Thus, the relay at the end of the line (R4 in the following
figure) should have the shortest tripping time.
This situation can be best observed from the schematics
and current-time characteristics below:
CKR-81T-96
MODELS
General
Operating Temperature
Dimension
Packing Weight
Quantity in 1 package
-5°C, +55°C
96x96mm
(PR24)
144x144mm
(PR17)
0,7 kg
1,5 kg
16 pcs
4 pcs
OVERCURRENT PROTECTION RELAYS
CKR Series
Dimensions
Connection Diagram
122
103
A- Single Phase
Overcurrent Protection Device
L1
7
8
9
1
L1
2
10
k
L
K
l
k
L
l
K
k
L
140
14
15
l
3
4
11
12
13
ECU
K
IL
140
L2
140
L3
105
+ 5
TYPE PR 17
+
6
85
70
Ko
Auxiliary device
ER-3Y
90
96
Ao
96
95
TYPE PR 24
7
8
9
2
3
IE
4
11
k K
K
l
L
l
L
12
13
k
l
K
k
K
k
K
k
L
l
L
l
L
l
+ 5
14
15
E
ECU
L
k
7
8
9
10
11
12
13
14
15
1
10
K
L1
+
6
B 3 - Earth Fault Overcurrent Protection Device
L3
1
L3
L2
IL
Ao
6
3
5
E
4
4
L1
7
8
9
10
11
12
13
14
15
L1
7
8
9
3
+ 5
K
+
k
K
k
K
k
24VDC
OR
2
220/230 VAC
6
Ko
Auxiliary device
ER-3Y
L2
2
ECU
L1
L2
ECU
ECU
L2
L3
L
l
L
l
L
1
l
1
2
3
IE
4
ECU
L3
B2 - Earth Fault
Overcurrent Protection Device
+
B1- Earth Fault
Overcurrent Protection Device
+
5
+
6
Ko
Auxiliary device
ER-3Y
Ao
The shown diagrams are only for typical application purposes.
L1
7
8
9
10
L
k
l
K
L
k K
l
L
k
l
14
15
L2
IL
L3
L2
E-Three Phase and Earth Fault
Overcurrent Protection Device
L3
L1
7
8
9
L3
3
10
L2
+ 5
E
K
k
K
k K
+
6
Ko
Auxiliary device
ER-3Y
L
l
L
l
L
IL
3
L1
Ao
K
+
14
15
l
7
8
9
10
4
11
12
13
k
L1
2
4
L1
L2
1
2
k
K
k K
k
5
+
6
L
l
L
l
L
l
Ko
Auxiliary device
ER-3Y
IE
L3
L2
1
2
IL
3
4
11
12
13
L1
14
15
E
+ 5
+
6
Ko
Auxiliary device
ER-3Y
Ao
Ao
pcs / carton
K
11
12
13
1
IE
ECU
L2
ECU
L3
D-Three Phase Overcurrent
Protection Device
ECU
C-Two Phase and Earth Fault
Overcurrent Protection Device
Product Code
CKR-93T
3 Phase + 1 Earth (Adjustable Inverse and Fixed Times for Phase & Earth) 85-265 VAC / DC
4
CKR-92T
2 Phase + 1 Earth ( '' ''
4
''
''
''
''
''
''
''
''
)
32
OVERCURRENT PROTECTION RELAYS
CKR Series
Tp
Tp
Tp
Tp: Time multiplier
33
Tp
Tp