ERL L-PRO 4000, User Manual

Page: 158 / 406

7 Acceptance/Protection Function Test Guide
7-12 L-PRO 4000 User Manual D02706R02.30
60 Loss of
Potential (LOP)
Test
Settings
• Voltage = 0.75 per unit phase-to-neutral fixed (In this case minimum op-
erate = 0.75 per unit = 0.75 * V
nominal
= 0.75 * 66.4 V = 49.8 V)
• I
1
Blocking = 10.0 A (positive sequence current that blocks LOP if
exceeded)
• 3
I0
Blocking = 1.0 A (zero sequence current that blocks LOP if exceeded)
Figure 7.10: Loss of Potential Logic (60)
60 Test Procedure:
1. In Relay Control Panel access relay Metering>Logic>Protection .
Monitor: 60 Alarm
2. Apply balanced 3-phase nominal voltages (66.4 V) to the relay terminals:
Ph A: 330, 66.4 V

0

Ph B: 331, 66.4 V

-120

Ph C: 332, 66.4 V

+120

Ph N: 333
3. Connect 3-phase current sources (0.5 A) to the relay terminals (must be
greater than 0.2 A (4% I
nominal
) to enable due to low set supervision, for
details see Figure 7.10: Loss of Potential Logic (60) on page 7-12).
Ph A: 300
–
301, 0.5 A

0

Ph B: 302
–
303, 0.5 A

-120

Ph C: 303
–
304, 0.5 A

+120

Observe: 60 Alarm = Low
4. Instantaneously reduce single-phase voltage to 48 V or less.
60 Alarm = High
Contact 2 Closed
5ms
12ms
0
17ms
50 Ipos
168
171
173
174
169
167
170
172
50 3I0
50 ILA (4% I nominal)
50 ILB (4% I nominal)
50 ILC (4% I nominal)
dVpos/dt < -3V/cycle
dVpos/dt > 3V/cycle
ABS | dIpos/dt | > 0.1A/cycle
27 VLa (0.75 pu fixed)
27 VLc (0.75 pu fixed)
27 VLb (0.75 pu fixed)
0
20ms
59 VLa (0.1 pu fixed)
59 VLc (0.1 pu fixed)
59 VLb (0.1 pu fixed)
175
176