Bender NGRM500 User manual

Quick-start guide ENNGRM5xx_D00373_08_Q_XXEN/11.2022
NGRM500 (HRG)
NGRM550 (LRG)
Neutral Grounding Resistor Monitor (NGR)

Intended use
The NGRM500 is only intended for use in high-resistance
grounded systems. The NGRM550 is only intended for
use in low-resistance grounded systems. In these sys-
tems, the NGRM5… monitors
• the current through the neutral grounding resistor
(NGR),
• the voltage between the star point of the transform-
er and ground (voltage drop across the NGR),
• the condition of the NGR.
This quick-start guide does not replace the operating
manual of the device.
Download: www.bender.de/manuals
Safety instructions
I Risk of electrocution due to electric shock!
Touching live parts of the system carries the risk of:
- An electric shock
- Damage to the electrical installation
- Destruction of the device
Before installing the device and before working on
its connections, make sure that the installation has
been de-energized. Observe the rules for working
on electrical installations.
Quick-start guide for
Type Supply voltage/Frequency range USArt. No. Manual
NGRM500 AC 48…240V, 40…70 Hz
DC 48…240V
B94013500 D00373
NGRM550 B94013550
Enclosure view (front, top, bottom)
SERVICE
TRIPPED
NGR FAULT
GROUND FAULT
ON MENU
RESET
DATAINFO
TEST
NGR Monitor
OK
NGR = 265Ω
I NGR = 0,01A
NGRM500
LINETRAXX®ΩAV
C5ERSRETHX1 50m
11 12 1421 22 24 31 32 34
Ground fault NGR fault Trip
NGRM500
Mounting (DIN rail, screw mounting)
2 x Click!
1.
2.
3.
1 x Click!
Ø M4
54 (2.12)
72 (2.83)
100 (3.94)
DIN rail Screw mounting
Dimension diagram (all dimensions in mm (in))
108 (4.25) 110 (4.33)
93
(3.66)
2 NGRM5xx_D00373_08_Q_XXEN/11.2022
NGRM500 (HRG), NGRM550 (LRG)

Star configuration
i
The "N" connection of the CD-series coupling device
should be as close to the transformer star point as
possible.
k
l
NGR
CT
R
s
(G1)
E (G)
N
CD...
PE PE
L1
L2
L3
VAQ
LINETRAXX®
NGRM5…
A1
A2
X1
Ethernet
RS
E
5
C
50m
6A
AC/DC
48...240 V
6A
11 12 14 21 22 24 31 32 34
Circuit breaker
NGR faultGround fault Trip
Connection X1
I1
I2
I3
A
B
M+
Q2
Q1
+
I1 Digital 1 (congurable: pulser, NGR method)
I2 Reset IN
I3 Test IN
AModbus RTU (A)
BModbus RTU (B)
Common
M+ Analog output
Q2 Open collector: Pulser OUT
Q1 Open collector: Device health
+Output for supply of external relays (+24V, max. 100 mA)
NGRM500 (HRG), NGRM550 (LRG)
NGRM5xx_D00373_08_Q_XXEN/11.2022 3

Measuring current transformer selection
Depending on the system to be monitored, a suitable measuring current transformer has to be chosen. All common
measuring current transformers (50 mA or 5 A on the secondary side) can be used. The following table helps you with
the choice:
System type AC + DC AC AC AC
INGR 1…25 A 5…25 A 5…1000 A 10…2000 A
f0…3800 Hz 42…3800 Hz 50/60 Hz 50/60 Hz
Transformation ratio
Bender measuring current
transformer
Measuring range (see
CTUB103 manual)
5 A 100:1
10 A 200:1
25 A 500:1
600:1
Connecting cable
max. 30 m max. 40 m max. 25 m (4 mm²/AWG 12)
max. 40 m (6 mm²/AWG 10)
provided cable
or 0.75…1.5 mm²/AWG 18…16
I
Δn
Type CTUB103 CTAC…,WS… CTB31…51 Any standard
current transformer can
be used.
CT: terminal k NGRM5…: 50 mA NGRM5…: 50 mA NGRM5…: 5 A NGRM5…: 5 A
CT: terminal l NGRM5…: CNGRM5…: CNGRM5…: CNGRM5…: C
24 V
S1(k) S2(l)
CTUB103
kl
CTB
WS…
kl
kl
CTAC…
4 NGRM5xx_D00373_08_Q_XXEN/11.2022
NGRM500 (HRG), NGRM550 (LRG)

Menu overview
1. Data meas. values
4. Pulser
3. History
5. Display
9. Info
History, Delete
Pulser, tImpuls
RNGR, INGR
HRG/LRG
system
CT
NGR
Field calibration
Usys (L-L), f, INGR nom, RNGR nom
CT primary, CT secondary, CT connection
10. Alarm Acknowledge, Reset, Test
RNGR,RNGR rel,Method, Rsense, Irms,Irms rel, Urms,Urms rel, Ifund,
Ifund rel, Ufund,Ufund rel, Iharm, Iharm rel, Uharm, Uharm rel,
6. HRG settings
7. Device settings Language, Clock, Interface, Display, Password, Factory setting,
Software, Service
2. Harmonics IU
Device information, Software information,
Clock and date information, Ethernet information
Ground fault relay
NGR relay
Trip relay
Analogue
Digital in/out
Buzzer
Mode, Relay test
Mode, Relay test
Mode, Relay test
Device OUT, Pulser OUT,
Digital 1, Reset IN, Test IN
Buzzer alarm, Buzzer test
Mode, Function
UNGR Trip, INGR Trip, >RNGR, <RNGR (HRG only), tNGR trip,
GF trip, tGF trip, Alarm stored, trestart,
Max. no. of restarts, Trip signal, Upper limit harmonics,
Lower limit harmonics
Method, Filter, Filter type, Filter size, Ignore values
Response
values
System
settings
8. Commissioning Setting Language, Clock, Usys L-L, f, INGR nom,
RNGR nom, CTprimary,CTsecondary, CTConnection, Field calibration
NGRM500 (HRG), NGRM550 (LRG)
NGRM5xx_D00373_08_Q_XXEN/11.2022 5

Maximum trip times t(GFtrip) for the CD-NGRM
used
The setting for tGF trip must under no circumstances be
longer than the maximum possible operating time of the
CD-NGRM coupling device.
The table shows an overview of the tGF trip settings for the
coupling device used (menu 6.4):
Usys
Coupling
device
Ground-fault
trip setting max. tGF trip
400…690V CD1000 on or o 48 h
CD1000-2
691…1000V
CD1000 on 300 s
CD1000-2 on or o 48 h
CD5000
1001…4300V CD5000 on or o 48 h
4301…14550V CD14400 on 60 s
CD25000 on 90 s
14551…25000V CD25000 on 10 s
Initial commissioning
The commissioning wizard (menu 8) queries the follow-
ing parameters; additional settings: menu 6.
Language (8.2) Select
Date (8.3) Set
Time (8.4) Set
Usys L-L (8.5) System voltage
Frequency (8.6) 50 or 60 Hz
INGR nom (8.7)
RNGR nom (8.8)
CT primary (8.9)
CT secondary (8.10)
CT connection (8.11) 50 mA or 5 A
Field calibration (8.12) Start or do not start
1. Setting the response values (menu 6.4)
• Trip threshold for voltage (UNGR)
• Trip threshold for current (INGR)
• Trip threshold for resistance (RNGR)
i
Low trip threshold values: may lead to false trip-
ping.
High trip threshold values: the device may not trip
at all
HRG system: Recommended minimum value
RNGR (tripping level 50 %)
Temperature range –40…+60 °C,
Field calibration at 20 °C
CD1000/CD1000-2 CD1000-2 CD5000 CD14400 CD25000
Usys 400 V 600 V 690 V 1000 V 2400 V 4200 V 6000 V 6600 V 7200 V 11000 V 14400 V 25000 V
INGR
1 A 231 Ω 346 Ω 398 Ω 577 Ω 1386 Ω — — — — — — —
5 A 46 Ω 69 Ω 80 Ω 115 Ω 277 Ω 485 Ω 693 Ω 762 Ω 831 Ω 1270 Ω 1663 Ω —
10 A (23 Ω) 35 Ω 40 Ω 58 Ω 139 Ω 242 Ω 346 Ω 381 Ω 416 Ω 635 Ω 831 Ω 1443 Ω
15 A (15 Ω) (23 Ω) (27 Ω) 38 Ω 92 Ω 162 Ω 231 Ω 254 Ω 277 Ω 423 Ω 554 Ω 962 Ω
20 A —(17 Ω) (20 Ω) 29 Ω 69 Ω 121 Ω (173 Ω) 191 Ω 208 Ω 318 Ω 416 Ω 722 Ω
25 A — — (16 Ω) (23 Ω) 55 Ω 97 Ω (139 Ω) (152 Ω) (166 Ω) 254 Ω 333 Ω 577 Ω
30 A ———(19 Ω) (46 Ω) 81 Ω (115 Ω) (127 Ω) (139 Ω) 212 Ω 277 Ω 481 Ω
40 A — — — — (35 Ω) 61 Ω (87 Ω) (95 Ω) (104 Ω) (159 Ω) 208 Ω 361 Ω
50 A — — — — (28 Ω) (48 Ω) —(76 Ω) (83 Ω) (127 Ω) (166 Ω) 289 Ω
100 A — — — — — (24 Ω) ————(83 Ω) (144 Ω)
() = Limited temperature range at any field calibration tem-
perature ±20 K
The temperatures must be within the limits of the operating
temperature range of –40…+70 °C
[for UL applications –40…+60 °C].)
6 NGRM5xx_D00373_08_Q_XXEN/11.2022
NGRM500 (HRG), NGRM550 (LRG)

2. System settings of the relays (menu 6.5)
The factory setting for the relays is fail-safe. In the case of
a test, the relays change state.
i
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 6.6)
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 (RNGR nom). In order to achieve high
accuracy, start the device and let it run for at least one
hour in the operating environment before carrying out
the field calibration.
i
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. The trip relay is switched
during field calibration!
4. RMS trip signal, fundamental frequency,
harmonics
The measured value which causes tripping can be select-
ed via the "Trip signal" parameter (menu 6.4.11). Trip sig-
nal can be:
• RMS: The RMS value of Ior Uover 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
i
In the "Harmonics" measured value display (menu
2) all spectral lines are always displayed. This is in-
dependent of the trip signal setting.
i
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).
5. Initial measurement
During device start, all measured values are recorded.
Factory settings
Menu Factory settings
Menu 6.1: HRG/LRG system
1. Usys (L-L) 400V
2. CD-NGRM CD1000
3. Frequency 50 Hz
4. INGR nom 5 A
5. RNGR nom 150 Ω
Menu 6.2: CT
1. CT primary 600
2. CT secondary 1
3. CT connection 50 mA
Menu 6.3: NGR
1. Method auto
2. Filter o
Menu 6.4: Response values
HRG LRG
1. UNGRTrip 60 %
2. INGR trip 60 %
3. > RNGR 150 % (HRG), 250 Ω (LRG)
4. < RNGR
(HRG only) – 50 % (HRG)
5. tNGR trip 4. tNGR trip 0 s
6. Ground-fault
trip
5. Ground-fault
trip on
7. tGF trip 6. tGF trip 5 s
8. Alarm stored 7. Alarm stored on
9. trestart 8. trestart 5 s
10. Max. no. of
restarts
9. Max. no.
restarts 2
11.Trip signal 10. Trip signal RMS
12. Upper limit
harmonic
11. Upper limit
harmonic 32
13. Lower limit
harmonic
12. Lower limit
harmonic
0
NGRM500 (HRG), NGRM550 (LRG)
NGRM5xx_D00373_08_Q_XXEN/11.2022 7

Menu Factory settings
Menu 6.5: System settings
1. Ground-fault relay Mode: Fail-safe
Rel.Test: on
2. NGR-fault relay Mode: Fail-safe
Rel.Test: on
3.Trip relay Mode: Fail-safe
Rel.Test: on
4. Analog
Mode: 4-20 mA
Function: RNGR (HRG)
INGR (LRG)
5. Dig. in/out
Device OUT: Fail-safe
Pulser OUT: Non-fail-safe
Digital 1: Pulser, Active high
RESET IN: Active high
TEST IN: Active high
6. Buzzer Buzzer alarm: o
Buzzer test: on
NGRM500 (HRG), NGRM550 (LRG)
Alle Rechte vorbehalten.
Nachdruck und Vervielfältigung
nur mit Genehmigung des Herausgebers.
Bender GmbH & Co. KG
Postfach 1161 • 35301 Grünberg • Deutschland
Londorfer Str. 65 • 35305 Grünberg • Deutschland
Tel.: [phone] • Fax: [phone]
E-mail: [email protected] • www.bender.de
All rights reserved.
Reprinting and duplicating
only with permission of the publisher.
Bender GmbH & Co. KG
PO Box 1161 • 35301 Grünberg • Germany
Londorfer Str. 65 • 35305 Grünberg • Germany
Tel.: [phone] • Fax: [phone]
E-mail: [email protected] • www.bender.de
UL File Numbers
E493737, E173157
Technical data
Rated voltage..................................................................................... 250 V
Overvoltage category............................................................................... III
Nominal supply voltage Us ............................................AC/DC, 48…240 V
for UL applications.....................................................AC/DC, 48…240 V
for AS/NZS 2081 applications ....................................AC/DC, 48…230 V
Tolerance Us....................................................................................±15 %
Tolerance Us(for UL applications) ........................................–50…+15 %
Tolerance Us(for AS/NZS 2081 applications)........................–25…+20 %
Frequency range Us............................................................ DC, 40…70 Hz
Power consumption (max.)...................................................≤ 7 W / 16 VA
Switching elements (ground-fault, NGR-fault, trip relays)
.........................Changeover contacts, configurable fail-safe/non-fail-safe)
Contact data acc. to IEC 60947-5-1
Rated operational voltage ............................................. AC 250 V/250 V
Utilization category ...........................................................AC-13/AC-14
Rated operational current AC...................................................... 5 A/3 A
Rated operational current AC (for UL applications)......................3 A/3 A
Rated operational voltage DC............................................220/110/24 V
Utilization category .........................................................................DC12
Rated operational current DC ................................................0.1/0.2/1 A
Minimum current..................................................... 1 mA at AC/DC > 10 V