Mitsubishi Electric MELPRO-A Series Instruction Manual page 8

Characteristics
(MDG-A3V type relay ＋ MZT type ZCT ＋ MPD-3 type ZVT combination)
Item
Ambient temperature: –20 to +60℃ (Under the state where dew condensation or freezing does not occur)
Relative humidity: 30 to 80% on daily average
Standard use
Altitude: 2000m or lower
conditions
・The state where abnormal vibration, shock, and inclination are not applied.
・The state where it is not exposed to harmful gas, excessive dust, and water droplet or vapor.
Setting: Zero-sequence voltage V
I
Input: V
0
Criteria: Within ±10% of each setting current at the maximum sensitivity angle
Setting: Zero-sequence current I
Operation value
Input: I
characteristics
Criteria: Within ±25% of each setting voltage at the maximum sensitivity angle
V
0
Reset value
90% or more of operating value (Both I
characteristics
Setting: Zero-sequence current I
Input: I
I
Phase
characteristics
Input: V
Operating time
characteristics
Resetting time
Input: V
characteristics
Criteria: 250ms±50ms
Setting: Zero-sequence current I
Overshoot time
Input: I
characteristics
Applied time: 0.05s
Criteria: The relay shall not operate.
Setting: Zero-sequence current I
Input: V0 = 3810V (MPD-3C primary), I0 = 30A (MZT primary)
High ground fault
Criteria: At the lead angle of 90°(V
current
characteristics
(Note) When the max. sensitivity angle is set to 10°and this product is applied to a system with ground
fault current exceeding 25A, use MZT-77D type or MZT-112D type ZCT.
= 150% of setting value
0
= 150% of setting value
0
V setting (%) 2
0
MPD-3C primary (V) 76.2
T terminal (V) 7.62
= 1000% of setting value, V
0
operating area (V standard):
0 0
Phase setting
Lag
Lead
Max. sensitivity angle 45°
(For non-grounding system)
Lead←
Operation
area
90°
115°
155°
= 0 → 150% of setting value, I
0
(at the maximum sensitivity angle)
Time setting
Instantaneous
0.2s
0.3s or more
= 150% of setting value → 0, I
0
= 400% of setting value, V
0
At the lag angle of 90°(V
Characteristics
= 2%, Operating time T = Instantaneous
0
= 0.1A, Operating time T = Instantaneous
0
2.5 3 4
95.3 114.3 152.4 190.5
9.53 11.43 15.24 19.05
and V )
0 0
= 0.1A, Zero-sequence voltage V
0
= 150% of setting value
0
Max. sensitivity angle
45°
45°±20°
135°±20°
0°
V
０
→Lag
25°
65°
90°
0.2 0.4 0.6 0.8 1.0A
Non-operation
area
180°
= 0 → 130% and 400% of setting value
0
Current Ratio to the setting current
130%
50～100ms
0.1～0.3s
±20% of setting time
= 130% and 400% of setting value → 0
0
= 0.1A, Zero-sequence voltage V
0
= 150% of setting value (at the maximum sensitivity angle)
0
= 0.1A, Zero-sequence voltage V
0
standard), the relay shall operate.
0
standard), the relay shall not operate.
0
8
5 6 7 7.5
228.6 266.7 285.8
22.86 26.67 28.58
= 2%, Operating time T = Instantaneous
0
Max. sensitivity angle
10°
+5°
80°
-30°
+30°
100°
-10°
Max. sensitivity angle 10°
(For reactor grounding system)
0°
V
０
Lead← →Lag
50°
Operation
area
90°
0.2 0.4 0.6 0.8 1.0A
Non-operation
area
130°
180°
400%
50～100ms
0.1～0.2s
±10% of setting time
= 2%, Operating time T = 0.2s
0
= 2%, Operating time T = Instantaneous
0
8 9 10
304.8 342.9 381
30.48 34.29 38.1
85°
90°
JEP0-IL9554