Bender NGRM750 Краткое руководство по эксплуатации - Страница 7

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2. System settings of the relays (menu 6.6)

The factory setting for the relays is fail-safe.

In the case of a test, the relays change state.

Fail-safe: The relay is energized during normal op-

eration and is de-energized

in the event of a fault

("fail-safe")

Non-fail-safe: The relay is de-energized in normal

operation and is energized in the event of a fault

("non-fail-safe")

3. Field calibration (menu 6.7)

During field calibration, all tolerances of the connected

CD-series coupling device and the NGR are considered.

The current measured value is calibrated to the set nomi-

nal value of the NGR (R

curacy, start the device and let it run for at least one hour

in the operating environment before carrying out the

field calibration.

For the field calibration the device must be in auto

mode (menu 6.3.1 = auto).

If the digital input I1 is used with "Digital 1 > NGR

method" (menu 6.6.5.3), "Method > external" (menu

6.3.1) must be selected and I1 must be active (see

manual).

The trip relay is switched during field calibration!

4. RMS trip signal, fundamental frequency, har-

monics

The measured value which causes tripping can be select-

ed via the "Trip signal" parameter (menu 6.5.11). Trip sig-

nal can be:

• RMS: The RMS value of I or U over the entire fre-

quency range (up to approx. 3.8 kHz).

• Fundamental frequency: Only the RMS value of the

fundamental frequency (50 or 60 Hz).

• Harmonics: The filtered RMS value on the selected

range of harmonics with

H0 = DC; H1 = fundamental frequency; H2 = 2 x funda-

mental frequency; ... H32 = 32 x fundamental frequency

In the "Harmonics" measured value display (menu

2) all spectral lines are always displayed. This is in-

dependent of the trip signal setting.

On the standard display, the trip signal is indicat-

ed as resistance (in Ω or %) or as current (in A or

%). The setting is entered in "Display" (menu 5).

). In order to achieve high ac-

NGR nom

5. Initial measurement

During device start, all measured values are recorded.

Factory settings

Menu 6.1: HRG/LRG system

1. U

sys (L-L)

2. CD-NGRM

3. Frequency

4. I

NGR nom

5. R

NGR nom

Menu 6.2: CT

1. CT primary

2. CT secondary

3. CT connection

Menu 6.3: NGR

1. Method

2. Filter

Menu 6.4: Phase monitor

1. Phase monitor

2. PT primary

3. PT secondary

Menu 6.5: Response values

HRG

1. U

NGR Trip

2. I

NGR Trip

3. > R

NGR

4. < R

(HRG only)

NGR

5. t

4. t

NGR trip

NGR Trip

6. Ground-fault trip

5. Ground-fault trip

7. t

6. t

GF Trip

8. Alarm stored

7. Alarm stored

9. t

8. t

restart

10. Max. no. of restarts 9. Max. no. of restarts

11. Trip signal

10. Trip signal

12. Upper limit

11. Upper limit

harmonic

13. Lower limit

12. Lower limit

harmonic

NGRM7xx_D00292_07_Q_XXEN/11.2022

NGRM700 (HRG), NGRM750 (LRG)

Factory settings

400 V

CD1000

50 Hz

5 A

470 Ω

600

50 mA

auto

off

LRG

60 %

150 % (HRG),

250 Ω (LRG)

—

50 %

0 s

yes

5 s

RMS