Tel :
82-32-817-4325
Fax :
82-32-817-4329
Resistors And
Resistive Applications
NEUTRAL GROUNDING RESISTORS LOAD BANKS
INTRODUCTION
RARA Neutral Grounding Resistors are designed to provide added
safety to industrial distribution systems by limiting ground fault
current to reasonable levels. In a typical grounded three phase
system, the NGR is connected directly to the earth ground. This can
cause high ground fault current (typically 10,000 to 20,000 amps)
and excessive damage to transformers, generators, motors, wiring,
and associated equipment. Installing a RARA Neutral Grounding
Resistor between neutral and ground limits fault current to safe
levels while still allowing sufficient current flow to operate fault
clearing relays
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custom designed for your particular system
durable, all stainless steel resistor elements
elements are well insulated from ground for added safety
corrosion resistant enclosures
several stages of assembly depending on shipping needs
Product
Notes
Our NGR elements fall into three categories: Strip, edge wound and wire wound types. The dimensions of these
range from thicknesses of 0.6-2.5mm and widths from 4-100mm. The element type depends on the power of the
NGR. Our enclosuresv have voltage ratings from 0.2KV to 72KV and meet IEEE32. We can manufacturer NGRs
with IP ratings up to IP54 and NEMA ratings up to NEMA3S.
Characteristics of Metal Resistive Elements
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reliable electrical characteristics
resistor contact points are spot or argon-welded eliminating contact defects
high resistance to mechanical vibration
advanced cutting and trimming technology ensures low resistance tolerance
easy maintenance and verification
Minimum Information Needed for Model Selection
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voltage rating [KV/R3]
current rating [A]
time rating [sec.]
resistance [ohms]
indoor/outdoor
ambient environmental conditions
Website :
http://www.raraohm.com
Email :
sg@raraohm.com
AISI-304 Neutral Grounding Resistors
RATED VOLTAGE
(Line to Neutral)
RATED CURRENT
TEMP. RISE(℃)
750
`
350
750
100A
350
750
200A
350
750
300A
350
750
400A
350
750
500A
350
GR3H-2001T
GR3H-2003T
GRL-1001T
GRL-1003T
GR3H-1001T
GR3H-2001S
GR3H-1003T
GR3H-2003S
GRL-501T
GRL-1001S
GRL-503T
GRL-1003S
GR3H-501T
GR3H-1001S
GR3H-503T
GR3H-1003S
10SEC
GRL-501S
440/√3V
30SEC
GRL-503S
10SEC
GR3H-501S
3.3/√3kV
3.45/√3kV
30SEC
GR3H-503S
RATED VOLTAGE
(Line to Neutral)
RATED CURRENT
TEMP. RISE(℃)
750
50A
350
750
100A
350
750
200A
350
750
300A
350
750
400A
350
750
500A
350
GR7H-501T
10SEC
GR7H-501S
6.6/√3kV
6.9/√3kV
30SEC
GR7H-503S
GR7H-503T
GR7H-1003S
GR7H-1003T
GR7H-2003S
GR7H-2003T
GR7H-3003S
GR7H-3003T
GR7H-4003S
GR7H-4003T
10SEC
22/√3kV
22.9/√3kV
30SEC
GR24H-503S
GR24H-503T
GR24H-1003S
GR24H-1003T
GR24H-2003S
GR24H-2003T
GR24H-3003S
GR24H-3003T
GR24H-4003S
GR24H-4003T
GR24H-5003S
GR24H-5003T
GR24H-501S
GR24H-501T
GR24H-1001S
GR24H-1001T
GR24H-2001S
GR24H-2001T
GR24H-3001S
GR24H-3001T
GR24H-4001S
GR24H-4001T
GR24H-5001S
GR24H-5001T
GR7H-1001S
GR7H-1001T
GR7H-2001S
GR7H-2001T
GR7H-3001S
GR7H-3001T
GR7H-4001S
GR7H-4001T
1. Resistance (R) = Line to neutral voltage (V) / Rated current (I) - Tolerance : ±10 percent
2. Power frequency withstand test(One minute)
-Rated 600V or less : <2 X Line voltage> + 1000V
-Rated over 600V : <2.25 X Line voltage> + 2000V
3. Listed neutral grounding resistors are designed, tested, and rated in accordance with ANSI/IEEE
Std 32-1972 (Reaffirmed 1990).
Website :
http://www.raraohm.com
Email :
sg@raraohm.com
Tel :
82-32-817-4325
Fax :
82-32-817-4329
Resistors And
Resistive Applications
AISI-304 Neutral Grounding Resistors Dimensions
Model
GRL-
GRL-
GRL-
GRL-
501S, 503S
501T, 503T
1001S & 3S
1001T & 3T
Dimensions(mm)
W
500
640
640
640
D
420
420
420
420
H
160
160
160
160
Model
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
3001T
3003S
3003T
4001S
4001T
4003S
4003T
Dimensions(mm)
W
640
640
640
640
640
640
640
D
690
690
780
600
690
690
1140
H
1120
1120
1580
660
1120
1120
1580
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
GR3H-
501S
501T
503S
503T
1001S
1001T
1003S
1003T
2001S
2001T
2003S
2003T
640
640
640
640
640
640
640
640
640
640
640
640
600
780
780
600
600
780
780
600
600
780
780
690
350
350
350
580
350
350
350
580
350
350
350
810
GR7H-
GR7H-
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
501S
501T
503S
503T
1001S
1001T
1003S
1003T
2001S
2001T
2003S
2003T
3001S
3001T
3003S
3003T
4001S
4001T
4003S
4003T
5001S
5001T
5003S
5003T
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
780
870
870
870
780
870
870
870
780
870
870
1410
780
960
960
1410
780
960
960
1410
870
960
960
1410
1110
1340
1340
1800
1110
1340
1340
1800
1110
1340
1340
1800
1110
1800
1800
1800
1110
1800
1800
Note1
1340
1800
1800
Note1
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
GR7H-
501S
501T
503S
503T
1001S
1001T
1003S
1003T
2001S
2001T
2003S
2003T
3001S
640
640
640
640
640
640
640
640
640
640
640
640
640
600
780
780
600
600
780
780
600
600
780
780
690
510
660
660
660
1120
660
660
660
1120
660
660
660
1580
660
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
G R 24 H -
Note1:
1800 + 1800 (mm)
