Easergy P5F30 - Underfrequency ANSI81 and ANSI81U / Operation delay

[PaterninaEnriqu]

Good morning.

I am participating in a project of two (2) bays of 69kV lines + one (1) transformer bay + eight (8) 11.4kV switchgears with Easergy P5 and P3 devices.

In this project, specifically for switchgears, I am running routine tests on an Easergy P5F30

Order Code P5F30-EECB-GADDH-AAAI
Firmware V01
Build version: 300.103

For functions f> </f> <> </ f </ f << I am testing the following settings:

fn:60Hz

Un:69kV

TT´s= 69kV/115sqrt(3)

Stage	Pick-up value [Hz]	Operation delay [s]
1	59.4	0.2
2	59.2	0.2
3	59	0.4
4	58.8	0.4
5	58.6	0.6
6	58.6	1

For the test I am sensing two output contacts associated with trip coils 1 and 2. Since I do not have a test case with an advanced module with which I can sense starts and trips via 61850, I support myself by programming a contact associated with the start of the function and downloading the disturbance record (DR).

Issue:

For all scenarios, it is not respecting the Operation delay, subtracting the set intentional delay, approximately between 70-80ms. (81U Stage 6 58.6 - 1s CMC256.png and 81U Stage 1 58.4 - 0.2s CMC256.png)

Question:

Should I take the "Star Time" described in the manual to defend this behavior to the customer?

Since I have tried devices from other manufacturers and the "Delay Time" is respected, adjusted both in 61850 and the physical sensing of the contacts, taking into account the operating times of these between 5-12ms (for fast and normal contacts).

Best regards.

[PaterninaEnriqu]

Question:

Should I take the "Star Time" described in the manual to defend this behavior to the customer?

[Jinlei_Xing · Accepted solution]

Hi Enrique,

Sorry for the late replies.

Currently in P5 relay, the setting "Operation delay" means the interval between the "fault inception" and the "relay trip". Your test measured the interval between "relay start" and “relay trip“.  So the "Start time" should be considered when you check the test results with the "Operation delay" setting. The typical "Start time" 80ms is applied to compensate the real time delay between "relay start" and "relay trip". So for setting Operation delay as 200ms, the practical timer is only 120ms  = 200ms - 80ms. 

P3 has the similar operation delay philosophy as P5. However, from P5 wave 4 release, such operation delay philosophy will be changed to a more conventional way as your test. The operation time delay setting means the interval between "start" and "trip".

BR,

Jinlei XING