6-2 High-resistance Grounding Equipment

Wye or Delta Systems—DS9181 (CSA Approved) 240, 480, 600 Volts

WHERE TO USE NOTE: The use of high-resistance Equipment Range
grounding on 600-volt maximum systems Taps are provided on the standard
The function of a high-resistance ground- precludes line-to-neutral loading. DS9181 grounding resistor to adjust for a
ing equipment is: system charging current maximum of 3.5
2. To provide an immediate warning when
the first ground fault occurs through an amps or less. Since the normal charging
1. To provide a ground for neutral of an alarm system. current for most 600-volt or less systems is
ungrounded three-phase power system, usually below one ampere, our standard
utilizing the high-resistance method. Us- 3. To provide a method for quickly locating equipment is adequate; however, for sys-
ing this equipment allows the system to and removing the fault before another tems with greater charging currents refer to
operate basically as an ungrounded sys- fault develops on another phase, thereby the Company. Data for estimating the sys-
tem. The equipment is designed to elim- preventing circuit outages due to double tem charging current is shown in
inate the danger of high transient over- line-to-ground faults. This is done by us- GEI-100010.
voltages during certain types of ground ing the pulsing ground current feature
faults. and portable detector.

DESCRIPTION OF OPERATION OF STANDARD EQUIPMENT—LOW VOLTAGE

The circuits used for low-voltage systems The voltage appearing across the resistor The portable hook-on detector is then
are shown in Fig. 1 and Fig. 2. will be sensed by the meter relay. Auxiliary used to trace the fluctuations in ground
During normal conditions, with no contacts in the control, operated by the current through the system to the point of
ground fault on the system, only a small meter relay, are available for remote indica- fault. After the ground point has been lo-
magnetizing current (capacitance-charging tion and annunciation of a ground. cated and removed from the system, the
current) flows in the grounding transform- A green indicating light on the equip- operator then resets the selector switch to
ers and no voltage appears across the resis- ment indicates the control voltage is avail- de-energize the pulse-cycle timing circuits.
tor. able and that the system is normal. When a The grounding transformer for delta sys-
When a ground fault occurs, the resistor fault develops, a red indicating light on the tems will consist of three single-phase trans-
limits the ground current to a low value. equipment will light and remain lighted un- formers connected wye-delta. For wye sys-
Taps are provided on the resistor to adjust til the ground fault is removed. tems, where system neutral is available,
the magnitude of the ground current in the To trace the ground fault, the operator these grounding transformers are not
range of 0.9 to 3.6 amperes, depending on turns the selector switch to the ‘‘pulse’’ po- needed.
the size of the system, so that the current sition. This initiates cycle timing, alternately
supplied by the resistor to a ground fault energizing and de-energizing a shorting
will be slightly greater than the system’s nat- contactor at the secondary resistor, result-
ural capacitance-charging current. ing in a rhythmic fluctuation in the magni-
tude of the ground current.
GROUNDING
RESISTORS

Fig. 1. 600 volts maximum wye systems Fig. 2. 600 volts maximum delta systems

Data subject to change without notice

 High-resistance Grounding Equipment 6-3

Wye or Delta Systems—DS9181 240, 480, 600 Volts

SPECIFICATIONS
Equipment Included in Standard 240-, 480-, or 600-
volt Wye and Delta Systems
1—Line Isolator, three phase, interlocked with the door
3—Line fuses, 600 volts, 10 amp, interrupt 200,000 amps RMS
symmetrical
3—Neutral deriving transformers, dry-type (delta system only)
1—Control power transformer (CPT)
1—Meter relay (double set point)
1—Pulsing contactor, set to produce approximately 40 current
pulsations per minute
1—Neutral-grounding resistor (separately mounted)†, cont. rated
1—Relay for pulsing contactor
1—Control relay, with interlocks for remote alarm
1—‘‘Ground Fault’’ red indicating light
1—‘‘Normal’’ green indicating light
Fig. 3. DS9181WB Type 1 wall-mounted 1—‘‘Normal-Pulse’’ selector switch
panel for 600-volt (max) wye or delta 1—TEST resistor
systems 1—TEST pushbutton (momentary type)
1—Instruction plate on door
1—Wall-mounted enclosure (floor mounted is optional)
1—Portable ground-current detector with carrying case. (Option-
al—must be ordered as a separate item.)
Fig. 4. DS9181 Type 1CV floor-mounted X—Control circuit operates from 120 volts supplied by secondary
panel for 600-volt (max) wye or delta of CPT.
systems X—All connections to control and annunciator circuits wired to
terminal boards
X—Cable entry from top or bottom
X—Optional Modifications (See page 6-7.)
† Resistor is mounted inside DS9181L floor-mounted panel.

DIMENSIONS
All dimensions in inches.
Type 1 (outline 273A3617 Sh. 1) Type 3 (outline 273A3617 Sh. 2)
Approximate Weight Approximate Weight
Wye - 225 pounds Wye - 275 pounds
Delta - 300 pounds Delta - 350 pounds

GROUNDING
RESISTORS

Fig. 5. Dimensions and weights of DS9181W (240-, 480- or 600 volt, wye or delta systems) in wall-mounted enclosure

Data subject to change without notice

6-4 High-resistance Grounding Equipment

Wye or Delta Systems—DS9181 2400, 4160 Volts

Equipment Range
Taps are provided on the standard usually below this, our standard equipment
DS9181 grounding resistor to adjust for a is adequate; however, for systems with
system charging current maximum of 5.8 greater charging currents refer to Com-
amps or less (maximum 3.3 amps or less for pany. Data for estimating the system charg-
4160 volts delta). Since the normal charging ing current is shown in GEI-100010.
current for most 4160-volt or less systems is

DESCRIPTION OF OPERATION OF STANDARD

EQUIPMENT—HIGH VOLTAGE
The system operation is the same as was sistor tap value should be set slightly higher
described for the 600-volt (max) systems. than the system’s natural capacitance-charg-
One line diagrams for 2400- or 4160-volt ing current. For example, if the system ca-
systems are as shown in Fig. 9 and 10. pacitance-charging current is measured at
Taps are provided on the secondary resis- 1.9 amperes, the resistor taps should be set
tor to adjust the magnitude of the ground for approximately 2 amperes ground cur-
current, in the range of 2 to 6 amperes (1.2 rent, with a periodic increase during puls-
to 3.5 amperes on 4160-volt delta). The re- ing to 4 amperes.
Fig. 6. DS9181, 4160-volt delta system in Type 1 floor-
mounted enclosure with resistors mounted on top
SPECIFICATIONS
Equipment included in standard 2400- or 4160-volt wye and delta systems: 1—Draw-out
line isolator with 1 line fuse (3 fuses for delta system)
1—Grounding transformer, dry-type (3 for delta system)
1—Meter relay
1—Door switch (DSW)
1—Pulsing contactor, set to produce approximately 40 current pulsations per minute
1—Neutral-grounding resistor (mounted on top of panel or separately mounted), cont.
rated
1—Relay for pulsing contactor
1—Control relay, with interlocks for remote alarm
1—Control-power disconnect switch
2—Control fuses
1—‘‘Ground Fault’’ red indicating light
1—‘‘Normal’’ green indicating light
1—‘‘Normal-Pulse’’ selector switch
1—‘‘TEST’’ pushbutton (momentary type)
1—Instruction plate on door
1—Floor-mounted enclosure (wall mounted not available)
1—Portable ground-current detctor with carrying case. (Optional—must be ordered as a
separate item.) Fig. 7. DS9181, 4160-volt delta system, panel doors
X—Control circuit operates from remote source supplied by purchaser open, with resistors mounted on top
X—All connections to control and annunciator circuits wired to terminal boards
X—Cable entry from top or bottom
X—Optional modifications (See Table 6, page 6-8 for description.)
GROUNDING
RESISTORS

Fig. 8. DS9181, 4160-volt delta system, in Type 3 floor-

mounted enclosure
Data subject to change without notice
 High-resistance Grounding Equipment 6-5

Wye or Delta Systems—DS9181 2400, 4160 Volts

DESCRIPTION OF OPERATION (Cont’d) DIMENSIONS

Fig. 9. 2400- or 4160-volt wye systems

D (In Inches) Net Weight (lbs)

Voltage Encl Type
Wye Delta Wye Delta
2400, 1 13.375 13.375 1800 2300
4160 1 18.50 13.375 2000 2500
2400, 3 22.06 22.06 2400 2900
4160 3 27.18 22.06 2600 3100
A Resistors may be mounted separate. See Table 3, page 6-7.
B Incoming terminal connection
C Recommended position for incoming power conduit

Fig. 11. Dimensions of DS9181HA or HC (2400- or 4160-volt wye or delta

systems)

Fig. 10. 2400- or 4160-volt delta systems

GROUNDING
RESISTORS

Data subject to change without notice

6-6 High-resistance Grounding Equipment

Wye or Delta Systems—DS9181 240, 480, 600, 2400, 4160 Volts

Ground-current Detector* (Cat # 245A2006P1) TABLE 1—240-, 480-, and 600-volt systems
The ground-current detector is a modified portable hook-on Standard wall-mounted panels
type ammeter and includes the following special features: Description
● Multi-range switch. Catalog Number DS9181W — — — — — ——
● Large window, suitable for conduits up to 5 inches nominal PANEL TYPE ‘ ‘ ‘‘ ‘

}
}
diameter. Standard, with pulser A ‘ ‘ ‘
● Removable arm to facilitate use in limited spaces where con- Standard, without pulser B-Use A form
NEC/Calif Code,
duits are closely adjacent. with pulser † C
● Shorting switch to provide transient protection while detector NEC/Calif Code,
is being positioned around conductors. without pulser † D-Use C form
● Closed magnetic core to minimize effects of stray fields. SYSTEM TYPE
● For use on systems rated up to 4160 volts nominal, the handle Delta, 60 Hertz DO
Wye, 60 Hertz Y1
is insulated making it suitable for use where cables are not in Delta, 50 Hertz OBS
conduit. Wye, 50 Hertz OBS
* Minimum quantity one (1) required at the installation site. SYSTEM VOLTAGE AND RELAY MODIFICATIONS †
240-volt, Standard 01
240-volt ⫹ UV 02-Use 04 form
240-volt ⫹ TR 03-Use 04 form
240-volt ⫹ UV ⫹ TR 04
480-volt, Standard 08
480-volt ⫹ UV 09-Use 11 form
480-volt ⫹ TR 10-Use 11 form
480-volt ⫹ UV ⫹ TR 11
600-volt, Standard 15
600-volt ⫹ UV 16-Use 18 form
600-volt ⫹ TR 17-Use 18 form
600-volt ⫹ UV ⫹ TR 18
GROUNDING RESISTOR MOUNTING
For separate mounting and wiring
by Customer. (Cannot be mounted
inside or on top of Panel) B
TYPE OF ENCLOSURE FOR
GROUNDING RESISTOR ‡
Fig. 12. Portable detector with carrying case Open (no enclosure) X
Indoor Cover 1
HOW TO ORDER DS9181 SYSTEMS Outdoor Weatherproof 3
MODIFICATIONS †
(See TABLES 1-6) None (standard) XX
AM & separate mounted CT (Delta form only) AM
Order by complete DS9181 catalog number. Holding relay, reset push button, AM, CT (Wye form only) HM
EXAMPLE: Quantity 1—Type 1 wall-mounted panel with pulser EQUIPMENT ENCLOSURES §
for 480-volt wye, 60-Hertz system. Type 1 1
Order 1—DS9181WAY108B1XX1 (from TABLE 1) Type 3 3
(includes grounding resistor in NEMA 1 enclosure for Type 12 C
separate mounting) and order 1—DS9181 Cat. No.
† See TABLE 6 for description of Modifications.
245A2006P1 ground-current detector with carrying
§ For dimensions of wall-mounted panels see Fig. 5, page 6-3.
case each from TABLE 4).
‡ Approximate dimensions of resistor:
W D H
Open 21⬙ 19⬙ 5⬙ (Fig. 23, Part 24,
page 3-2)
Indoor Cover 22⬙ 21⬙ 7⬙ (Fig. 23, Part 24,
⫹ Note 1, page 3-10)
Outdoor Weatherproof 28⬙ 27⬙ 11⬙ (Fig. 24, Part 25,
Page 3-11)
GROUNDING
RESISTORS

Data subject to change without notice

 High-resistance Grounding Equipment 6-7

Wye or Delta Systems—DS9181 240, 480, 600, 2400, 4160 Volts

HOW TO ORDER (Cont’d)
TABLE 2—240-, 480-, and 600-volt systems TABLE 3—2400- and 4160-volt systems
Optional floor-mounted panels Standard floor-mounted‡ panels with pulser
Description Description
Catalog Number DS9181L — — — — — — Catalog Number DS9181H — — — — — — —
PANEL TYPE ‘ ‘ ‘ ‘ ‘

}
PANEL TYPE ‘ ‘ ‘ ‘

}
Standard, with pulser A ‘ ‘
Standard, with pulser A ‘ ‘ NEC/Calif Code,
Standard, without pulser B-OBSOLETE Use A form with pulser C
NEC/Calif Code,
with pulser* C SYSTEM TYPE
NEC/Calif Code, Delta, 60 Hertz D0
without pulser* D-OBSOLETE Use C form Wye, 60 Hertz Y1
Delta, 50 Hertz D2-OBSOLETE
SYSTEM TYPE Wye, 50 Hertz Y3-OBSOLETE
Delta, 60 Hertz D0
Wye, 60 Hertz Y1 SYSTEM VOLTAGE AND
Delta, 50 Hertz D2-OBSOLETE RELAY MODIFICATIONS*
Wye, 50 Hertz Y3-OBSOLETE 2400-volt, Standard 01
2400-volt ⫹ UV 02-Use 04 form
SYSTEM VOLTAGE AND 2400-volt ⫹ TR 03-Use 04 form
RELAY MODIFICATIONS* 2400-volt ⫹ UV ⫹ TR 04
240-volt, Standard 01 4160-volt, Standard 08
240-volt ⫹ UV 02-Use 04 form 4160-volt ⫹ UV 09-Use 11 form
240-volt ⫹ TR 03-Use 04 form 4160-volt ⫹ TR 10-Use 11 form
240-volt ⫹ UV ⫹ TR 04 4160-volt ⫹ UV ⫹ TR 11
480-volt, Standard 08 3300-volt, Standard 15-OBSOLETE
480-volt ⫹ UV 09-Use 11 form 3300-volt ⫹ UV 16-OBSOLETE
480-volt ⫹ TR 10-Use 11 form 3300-volt ⫹ TR 17-OBSOLETE
480-volt ⫹ UV ⫹ TR 11 3300-volt ⫹ UV ⫹ TR 18-OBSOLETE
600-volt, Standard 15
600-volt ⫹ UV 16-Use 18 form GROUNDING RESISTOR MOUNTING
600-volt ⫹ TR 17-Use 18 form Panel mounted (on top in own enclosure) A
600-volt ⫹ UV ⫹ TR 18 Shipped separate in own enclosure¶ B
GROUNDING RESISTOR MOUNTING TYPE OF ENCLOSURE FOR GROUNDING RESISTOR
Mounted and wired inside Open (no enclosure—all systems) 0
AX
equipment enclosure Type 1 (4160 volts wye) 1
Type 3 (4160 volts wye) 2
MODIFICATIONS*
None (standard) XX Type 1 (4160 volts delta, 2400 volts wye or delta) 3
CT and AM AM Type 3 (4160 volts delta, 2400 volts wye or delta) 4
Holding Relay, Reset push button, Ammeter, CT MODIFICATIONS*
(Wye form only) HM Holding Relay, Reset push button, Ammeter, CT HM
EQUIPMENT ENCLOSURES None (standard) XX
Type 1 CV† 1 CT and AM AM
Type 3 CV 3 EQUIPMENT ENCLOSURES ␭
Type 12 CV C Type 1 1
Type 3 3
Type 12 C
Approximate Dimensions and Weights
W⫻D⫻H With Pulser Without Pulser
Equipment In Pounds In Pounds
Enclosure (In Inches)
Wye Delta Wye Delta TABLE 4—Ground-current detector (modified porta-
Type 1CV 20 ⫻ 20 ⫻ 90 600 700 575 675
Type 3CV 20 ⫻ 20 ⫻ 100 1000 1100 975 1075 ble hook-on type ammeter) and carrying case
Type 12CV 20 ⫻ 203⁄4 ⫻ 93 650 750 625 725 Maximum System
Cat. No. Voltage
245A2006P1 4160
FOOTNOTES FOR TABLES 2 & 3
* See TABLE 6 for description of modifications.
† CV is convection cooled.
‡ Wall-mounted enclosure not available for 2400- and 4160-volt applications.
¶ Refer to Company for dimensions. Resistor is for separate mounting and wiring by
Customer.
␭ Refer to Fig. 11, page 6-5, for dimensions and weights.

TABLE 5—(Description of modifications applicable to all panels)

Mod. Item Function
UV Undervoltage Relay Drops out on low voltage and provides auxiliary contacts for meter relay failure remote alarm.
GROUNDING
RESISTORS

TR Timing Relay Prevents nuisance tripping on temporary transient faults.

NEC/Calif. Code Door Switches Allows panel to meet California Code and NEC.
CT Current Transformer Detects ground current
AM Ammeter Indicates ground current

Data subject to change without notice

6-8 Neutral Grounding Resistors

Type DS300C Stainless-steel Neutral Grounding Resistors

WHERE TO USE 90 days per year with an average ambient ond or extended-time rating have zero (0)
Use for resistance grounding of industrial not exceeding 30 C. continuous-duty-current rating.
power systems. Connect between ground STEADY STATE Tests
and neutral of wye-wound transformers or The IEEE standards have established Standard factory tests performed on the
generators. for the continuous-current-rated neutral 85A and DS300C resistor consist of resis-
Neutral grounding resistors are rated in grounding resistors an allowable tempera- tance measurement and applied potential
line-to-neutral voltage, initial current am- ture rise of 385 C under steady-state condi- tests only in accordance with routine tests as
peres and allowable-time-on. The line-to- tions. For the extended-time rating, a tem- defined by IEEE-32-1972, Sections 10.1.4
neutral voltage corresponds to the system’s perature rise of 610 C is permitted for and 10.3.2 (second paragraph), respec-
voltage divided by 1.732. The initial current stainless-steel resistors. Thus, if the lower tively.
is the current which would flow if rated temperature rise is desired for stainless- EQUIPMENT DESCRIPTION
voltage were present and resistance not af- steel-type resistors or if the resistor is to be
fected by temperature rise. DS300C Stainless-steel Resistors
on for an average above 90 days per year, a
Listed neutral grounding resistors are de- steady-state rating should be specified. (Open frame)
signed, tested, and rated in accordance with DS300C neutral grounding resistors con-
IEEE Standards No. 32-1972. Mine Service Requirements sist of ceramic-core ribbon-wound units ar-
Where neutral grounding resistors have ranged in tiers within an open frame. (Fig.
been specified for mining service applica- 1). Each unit is insulated from the tier struc-
tions, the Department of the Interior, Bu- ture. For systems above 600 volts, the frame
reau of Mines-Mandatory Safety Standards assembly is supported on ANSI-70 gray in-
for Coal Mines, sections 77.80-1 and 77.90-1, sulators rated 7.5 kV or higher to provide
specifies that ‘‘the ground fault current rat- insulation from ground. The standard
ing of grounding resistors shall meet the frame is constructed of hot dipped galva-
extended time rating’’ set forth in AIEE #32 nized steel with zinc plated hardware. (Op-
(IEEE #32-1972). Therefore, an extended tional frame constructions available are alu-
time rating should be specified for such ap- minum or stainless steel, each with stainless-
plications. steel hardware. Refer to company for
quotation.)
Typical grounding resistor schematic Seismic Shock Requirements
Where the application requires the neu-
SERVICE REQUIREMENTS tral grounding resistor to be rated for seis-
The two classes of service requirements for mic shock, specific requirements in terms of
neutral grounding resistors, as established by magnitude and frequency of the vibration
IEEE Standard 32-1972, are ‘‘steady state’’ should be obtained.
and ‘‘rated time.’’
Hazardous Location Requirements
RATED TIME In areas where fire or explosion hazards
Ten-second Rating—This is the shortest may exist, the temperature rises allowed by
time rating applied to neutral grounding IEEE-32-1972 are likely to exceed the ig-
devices which are used to reduce the nition temperature of the gas or vapor in-
ground current that may flow through a volved. It will be necessary to refer requests
piece of equipment. The current permitted for neutral grounding resistors for hazard-
is usually considerably greater than the full- ous locations to the company for a quota-
load current, so that dependence must be tion, specifying the ignition temperature in
placed upon the relay operation to prevent degrees celsius of the gas or vapor involved. Fig. 17. DS300C stainless-steel resistor in open frame
damage not only to the neutral device but Resistors will be designed for a maximum with support insulators
also to the main equipment. operating temperature of the resistive ele-
One-minute Rating—A common use of ment not to exceed 80 percent of the igni-
neutral grounding devices has been to limit tion temperature. DS300C Stainless-steel Resistors
ground currents on outgoing feeders dur-
ing faults to ground in order to reduce dam-
Altitudes above 3300 Ft (1000 M) (Open Frame) (Cont’d)
Resistors listed in this section are designed
age at the fault, limit overvoltages between Line and ground connections on DS300C
and rated for use at altitudes not exceeding
sound phases and ground, and improve resistor are external to frame and consist of
3300 ft (1000 M). For applications at higher
voltage regulation. through-stud-type entrance bushings with
altitudes, it will be necessary to refer to the
Extended-time Rating—For all applica- 5/8-inch - 11 stud.
company for a quotation.
tions where a ground fault is permitted to For systems with line-to-neutral, voltages
persist for longer than ten minutes, the Resistance Tolerance greater than 4160 volts, resistor will consist
grounding device should have a rating The listed 85A and DS300C resistors are of two or more frames. Frames may be
based upon the temperature reaching a manufactured to a resistance tolerance of stacked (2-high frames maximum) for most
constant maximum value, but selected on plus or minus 10 percent of the nominal fur- 10- and 60-second ratings.
the basis that such operation will be infre- nished value. DS300C open resistors can be installed
Rated Current
GROUNDING

quent. The temperature rise permitted may indoors or outdoors. No weather-protective

RESISTORS

be higher than the standard temperature The rated current for a neutral ground- enclosure is required. Support insulators
rise for steady-state service, assuming that ing resistor is the initial value of current, are shipped separately to prevent breakage
operations at maximum temperature will assuming a constant voltage is applied to the in transit. See page 4-13 for principal char-
not be required for more than an average of resistor. Resistors with ten-second, 60-sec- acteristics.
Data subject to change without notice
 Neutral Grounding Resistors 6-9

Type DS300C Stainless-steel Neutral Grounding Resistors (Cont’d)

EQUIPMENT DESCRIPTION (Cont’d)
DS300C Resistor with Bolt-on The open frame resistor is then sur-
rounded at top and 4 sides by a self-support-
Ventilated Covers ing screen enclosure that provides adequate
Bolt-on ventilated covers (attached to all electrical clearance from the resistor frame
six sides of the resistor frame) are intended based on system voltage. The safety enclo-
to protect the resistor from falling objects, sure is bolted to the floor (on concrete pad)
and prevent entry of birds and rodents. by purchaser. There is no bottom screen.
Cover plates are furnished for the lifting Sides are removable for customer access.
holes in the resistor frame. The ventilated The screens are constructed of galvanized
covers are constructed of hot dipped galva- expanded metal with 1.2-inch by 2.6-inch
nized steel with 0.25-inch ⫻ 1.50-inch rectan- diamond-shaped openings.
gular openings spaced 0.2-inch apart, provid- Entrance of the purchaser’s incoming
ing approximately 49-percent opening for neutral connection is normally made
ventilation. Refer to Fig. 18. through the top screen utilizing an optional
stud-type entrance bushing. (Refer to TABLE
1, page 4-20.) Fig. 20. Stand with 4-foot legs and grounded
galvanized safety-screen enclosure
Stands
for means of connecting customer’s incom-
DS300C Resistor Stand ing neutral conductor to the resistor. These
Resistor mounting stands are structures ANSI-70 light gray bushings are ‘‘assembled
which elevate the resistor frame (frames) through stud’’ type rated 400 amperes con-
above ground level and can be used to pro- tinuous, which is adequate for use with all
vide personnel safety (refer to Fig. 20). The catalog-listed DS300C resistors.
stand provides support for the resistor and Optional universal clamp-type terminal
is available with either 4-foot or optional assembly for entrance bushing is available
8-foot legs. for use with copper or aluminum cable
The standard offering is a stand assembly from Size #2 to 600 MCM.
made with steel angle legs and support
members which are hot dipped galvanized DS300C Current Transformers
steel for outdoor service. The top of the (CT)
Fig. 18. DS300C neutral-grounding resistor with stand is covered with galvanized welded-wire JKW wound-type current transformers are
ventilated covers attached to frame screening. available for applications up to 15 kV max-
The stand includes a grounded safety- imum with a maximum ratio of 800:5 for
DS300C Resistor with Grounded screen enclosure. Standard enclosure is gal- JKW-3 (5 kV) and JKW-4 (8.7 kV) and
Safety-screen Enclosures vanized expanded-metal construction (as 1200:5 for JKW-5 (15 kV). These current
previously described). transformers may be used indoors or out-
For indoor or outdoor pad-mounted ap- All stands with the grounded safety enclo- doors without a weather-protective enclo-
plications on systems rated greater than 600 sure include mounting provisions on the sure.
volts line-to-line, the DS300C open frame top screen for one entrance bushing, one The bottom insulators for resistor frame
resistor with grounded safety-screen enclo- stand-off insulator and one JKW current are commonly referred to as ‘‘stand-off in-
sure should be used to provide for person- transformer, each rated up to 15 kV. The sulators’’ or ‘‘support insulators’’ and are
nel safety (Refer to Fig. 19). current transformer may be mounted out- included in the price of the resistor.
side on the top screen or suspended from
the top screen inside the enclosure (Refer DS300C Resistor Terminations
to Fig. 31 and 32). Type DS300C resistors are supplied with
Stands with 4-foot legs always include the line and ground connection points external
grounded safety enclosure to provide per- to the frame consisting of through stud type
sonnel protection, because the closest elec- entrance bushings with 5/8-inch - 11 copper
trical live point would be a maximum of 4 studs.
feet 9 inches above ground level.
All stands and safety enclosures are bolted DS300C Cabling
construction. Where the resistor rating requires two
All stands are shipped partially assem- frames or more and the frames are stacked,
bled. Safety enclosures used with the stands the connection between frames is included.
may be shipped completely unassembled or Where the rating requires two or more
assembled (depending on size). frames that are not stackable (such as ex-
tended time ratings), the connection be-
DS300C Entrance Bushing tween frames must be supplied by pur-
GROUNDING
RESISTORS

Entrance bushings are available for chaser. Cabling to and from entrance
Fig. 19. DS300C resistor in grounded safety-screen mounting on top screen of pad-mounted or bushing and current transformer must also
enclosure stand-mounted safety enclosures to allow be supplied by the purchaser.

Data subject to change without notice

6-10 Neutral Grounding Resistors

Type DS300C Stainless-steel Neutral Grounding Resistors (Cont’d)

Specifications–DS300C Stainless-steel Resistors
Characteristic or Property DS300C Stainless-steel Type
RESISTANCE MATERIAL
a. Short time rating 10 minutes or below a. AISI-430 chrome stainless steel or AISI-406 iron, chromium, stainless steel as determined by rating
b. Extended time ratings b. AISI-406 iron, chromium, aluminum, stainless steel
TEMPERATURE RISE (in accordance with IEEE-32
Standards). 30 C ambient
a. Short time ratings a. 760 C rise
b. Extended time ratings* b. 610 C rise
c. Continuous ratings c. 385 C rise
TEMPERATURE COEFFICIENT OF a. AISI-430 .00103
RESISTANCE b. AISI-406 .00016
CHANGE IN RESISTANCE WITH TEM-
PERATURE (over the Operating Temperature
Range)
a. Short time ratings a. 90% increase
b. Extended time ratings—Per IEEE-32 b. 13% increase
The stainless-steel type resistors are inherently corrosion resistant and virtually immune to progressive
pitting and rusting. The ceramic insulators are not appreciably affected by exposure to condensation,
CORROSION RESISTANCE dust and other foreign materials. These resistors may be used outdoors completely exposed to the
weather without an enclosure.
RESISTANCE TOLERANCE ⫾ 10 percent
GROUNDING
RESISTORS

Data subject to change without notice

 Neutral Grounding Resistors 6-11

Type DS300C Stainless-steel Neutral Grounding Resistors—10-second Rating

for Indoor or Outdoor Service
Initial Total Resistance—Ohms Dimensions
Resistor Catalog Number of Enclosure or Stand
Current in Nominal Fig. Part
Calculated Number DS300C Frames Group Number
Amperes Furnished No. No.
139 VOLTS LINE-TO-NEUTRAL (240-VOLT SYSTEM) 10-SECOND RATING
100 1.390 1.33 139A100ⴱ714A 1 23 1 44
200 .695 .69 139A200ⴱ702A 1 23 1 44
277 VOLTS LINE-TO-NEUTRAL (480-VOLT SYSTEM) 10-SECOND RATING
100 2.77 2.76 277A100ⴱ744A 1 23 2 44
200 1.39 1.39 277A200ⴱ633A 1 23 1 44
400 .69 .69 277A400ⴱ702A 1 23 1 44
1390 VOLTS LINE-TO-NEUTRAL (2400-VOLT SYSTEM) 10-SECOND RATING
100 13.9 14.4 1390A100ⴱ312B 1 24 4 46
200 6.95 7.20 1390A200ⴱ161B 1 24 4 46
300 4.63 4.60 1390A300ⴱ110B 1 24 4 46
400 3.48 3.68 1390A400ⴱ108B 1 24 3 44
500 2.78 2.96 1390A500ⴱ160B 1 24 3 44
600 2.32 2.48 1390A600ⴱ212B 1 3 44
2400 VOLTS LINE-TO-NEUTRAL (4160-VOLT SYSTEM) 10-SECOND RATING
25 96 96.6 2400A25ⴱ435C 1 24 10 46
50 48 47.5 2400A50ⴱ423C 1 24 7 46
100 24 24 2400A100ⴱ317C 1 24 6 44
200 12 12 2400A200ⴱ167C 1 24 6 44
300 8 7.82 2400A300ⴱ117C 1 24 7 46
400 6 5.98 2400A400ⴱ113C 1 24 6 44
500 4.8 4.81 2400A500ⴱ165C 1 24 6 44
600 4.0 4.03 2400A600ⴱ217C 1 24 6 44
800 3.0 3.06 2400A800ⴱ274C 1 24 7 46
1000 2.4 2.38 2400A1000ⴱ325C 1 24 7 46
1200 2.0 2.04 2400A1200ⴱ377C 1 24 7 46
1600 1.5 1.53 2400A1600ⴱ430C 1 10 46
2000 1.2 1.19 2400A2000ⴱ469C 1 24 10 46
4160 VOLTS LINE-TO-NEUTRAL (7200-VOLT SYSTEM) 10-SECOND RATING
25 166.4 165 4160A25ⴱ449C 1 24 14 47
50 83.2 85 4160A50ⴱ433C 1 24 10 46
100 41.6 41.5 4160A100ⴱ327C 1 24 9 45
200 20.8 20.8 4160A200ⴱ177C 1 24 9 45
300 13.87 13.8 4160A300ⴱ127C 1 24 9 45
400 10.4 10.6 4160A400ⴱ123C 1 24 8 46
500 8.32 8.51 4160A500ⴱ175C 1 24 8 46
600 6.93 7.13 4160A600ⴱ227C 1 24 8 46
7200 VOLTS LINE-TO-NEUTRAL (12,470-VOLT SYSTEM) 10-SECOND RATING
100 72 73.6 7200A100ⴱ325G 2 25 108 49
200 36 36.8 7200A200ⴱ175G 2 25 108 49
300 24 23.9 7200A300ⴱ125G 2 25 109 48
400 18 18.4 7200A400ⴱ120G 2 25 107 48
500 14.4 14.8 7200A500ⴱ172G 2 25 107 48
600 12 12.4 7200A600ⴱ224G 2 25 107 48
800 9.0 8.96 7200A800ⴱ336G 2 25 109 48
1000 7.2 7.28 7200A1000ⴱ333G 2 25 109 48
8000 VOLTS LINE-TO-NEUTRAL (13,900-VOLT SYSTEM) 10-SECOND RATING
100 80 83 8000A100ⴱ327G 2 25 109 48
200 40 41.6 8000A200ⴱ177G 2 25 109 48
300 26.7 27.6 8000A300ⴱ127G 2 25 109 48
400 20 20.2 8000A400ⴱ122G 2 25 108 49
500 16 16.3 8000A500ⴱ174G 2 25 108 49
600 13.3 13.0 8000A600ⴱ225G 2 25 108 49
800 10.0 10.2 8000A800ⴱ283G 2 25 109 48
1000 8.0 8.40 8000A1000ⴱ335G 2 25 109 48
1200 6.67 6.72 8000A1200ⴱ386G 2 25 109 48
GROUNDING
RESISTORS

1600 5.0 5.10 8000A1600ⴱ442G 2 25 113 49

2000 4.0 4.06 8000A2000ⴱ481G 2 25 113 49
* If resistor open frame, insert ‘‘A’’ in this space.
If resistor with bolt-on covers, insert ‘‘B’’ in this space.

Data subject to change without notice

 6-12 Neutral Grounding Resistors

Type DS300C Stainless-steel Neutral Grounding Resistors

MODIFICATIONS—DS310 Enclosures and/or Stands and Accessories
Using TABLE 1 below, select complete DS310 catalog number for enclosure and/or stand assembly and accessories required for the
application. (When an enclosure and/or stand assembly is selected from TABLE 1, a complete DS310 catalog number is required. Refer
to pricing example on page 4-13.)

TABLE 1—Enclosures, Stands and Accessories

Catalog Number DS310 — — — — — — — — —
TYPE OF ENCLOSURE OR STAND ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘
Galvanized safety-screen enclosure .......................................... .......................................... A
Aluminum louvered safety enclosure ......................................... ......................................... B
Galvanized-steel stand with 4 ft legs and galvanized safety screen enclosure ........ ........
For resistor - one frame or two frames stacked.............................................................. E
For resistor - two frames side by side ...................................... ...................................... M
Galvanized-steel stand with 8 ft. legs, and galvanized safety screen enclosure. ..............
For resistor - one frame or 2 frames stacked ................................. ................................. K
Galvanized-steel stand with 8 ft. legs, no enclosure ..........................................................
For resistor - one frame or 2 frames stacked ................................. ................................. H
No enclosure, no stand .................................................... .................................................... N
CURRENT TRANSFORMER FUNCTION
Without CT mounting provisions ................................................... ................................................... 0
With CT mounting provisions ..................................................... ..................................................... 1
ENCLOSURE OR STAND GROUP NUMBER
Insert group number from last column of resistor pricing tables, pages 4-14 to 4-18 here
(Note: Price adder per group no. depends on type of enclosure or stand.)
GROUP NUMBER TYPE OF ENCLOSURE OR STAND
00 ................................................... ................................................... N or H
44 ................................................... ................................................... A, E or K
46 ................................................... ................................................... A, E or K
47, 48, 49 ............................................. ............................................. A, E or K
30, 32 ................................................ ................................................ A or M
33, 41 ................................................ ................................................ A or M
35, 37, 39 ............................................. ............................................. A or M
44 ....................................................................................................... B
46 ................................................... ................................................... B
47, 48, 49........................................................................................... B
ENTRANCE BUSHING AND STAND OFF INSULATORS
None ..................................................................................... ..................................................................................... N
Entrance bushing only: .................... .................... 7.5 kV ........................................ ........................................ A

{ 15.0 kV ........................................ ........................................

23.0 kV ........................................ ........................................
34.5 kV ........................................ ........................................
B
C
D
Stand-off Insulator only:.................... .................... 7.5 kV ................................................................................. F

{ 15.0 kV ........................................ ........................................

23.0 kV ........................................ ........................................
34.5 kV ........................................ ........................................
G
H
J
Entrance bushing and Stand-off Insulator: ..... ..... 7.5 kV ........................................ ........................................ L

{ 15.0 kV ........................................ ........................................

23.0 kV ........................................ ........................................
34.5 kV ........................................ ........................................
M
P
R
TERMINALS
Cable lugs for resistors for Size #2 to 600 MCM cable†
None required...................................................................................................................................................................... 0
1 lug .......................................................................................... .......................................................................................... 1
2 lugs ......................................................................................... ......................................................................................... 2
4 lugs ......................................................................................... ......................................................................................... 4
6 lugs ......................................................................................... ......................................................................................... 6
Cable or tube clamp for stand-off insulator
None required.................................................................................................................................................................................. 0
1 - for cable size #6-500 MCM or tube 1⁄8’’-1⁄2’’ IPS ........................................................... ........................................................... 1
1 - for cable size #4/0-1250 MCM or tube ⁄4’’-1 IPS ......................................................................................................................
1 2
RESISTORS

Entrance bushing terminal assembly for #2-600 MCM cable

None required ............................................................................................... ............................................................................................... 0
1 Asm ..................................................................................................... ..................................................................................................... 1
2 Asm ..................................................................................................... ..................................................................................................... 2
Ground clamp for leg of stand
None required ..................................................................................................... ..................................................................................................... 0
1-for cable size #8 solid to #4 stranded ................................................................................. ................................................................................. 1
1-for cable size #4 solid to #2/0 stranded ................................................................................ ................................................................................ 2
1-for cable size #2/0 solid to #250 MCM ................................................................................ ................................................................................ 3
1-for cable size 300 MCM to 500 MCM ................................................................................. ................................................................................. 4
1-Ground lug for enclosure or stand (for cable size #2 to 600 MCM) .......................................................... .......................................................... 5
CURRENT TRANSFORMER (1 only)
(Refer to TABLE 2 for Form Letters. Selection of CT based on voltage and ratio.)
None required (Form NN)...................................................................................................................................................................................................... *
5.0 kV class Type JKW-3 (Forms AA-AR).............................................................................................................................................................................. *
8.7 kV class Type JKW-4 (Forms BB-BR).............................................................................................................................................................................. *
15.0 kV class Type JKW-5 (Forms CA-CT) ............................................................................................................................................................................ *
*Insert TWO letter form.

† When ordering resistors only (open frame or with bolt-on cover) cable lugs may be ordered as a separate item. by Cat. No. 259A5970G1.

Data subject to change without notice

 Neutral Grounding Resistors 6-13

Type DS300C Stainless-steel Neutral Grounding Resistors

DIMENSIONS (FOR ESTIMATING ONLY)

All dimensions in inches.
Outlines: 273A4742-open frame
273A4733-with covers (600V)
Dimensions Max. Weight
Part in Inches Front (Lb)
No. View Open With
Width B Height D Frame Covers
1* ... ... 17 ⁄ 21 3⁄4
58 E 160 175
2* ... ... 22 5⁄8 9 1⁄2 E 190 205
3* ... ... 27 5⁄8 9 1⁄2 E 220 240
4* ... ... 32 5⁄8 9 1⁄2 E 250 270
5 22 1⁄2 12 22 5⁄8 9 1⁄2 F 275 300
6 22 1⁄2 12 27 5⁄8 9 1⁄2 F 340 370
7 22 1⁄2 12 32 5⁄8 9 1⁄2 F 390 420
8 22 1⁄2 12 37 5⁄8 9 1⁄2 F 450 480
9 37 1⁄2 27 27 5⁄8 9 1⁄2 F 520 565
10 37 1⁄2 27 32 5⁄8 9 1⁄2 F 620 665
11 37 1⁄2 27 37 5⁄8 9 1⁄2 F 720 765
12 37 1⁄2 27 42 5⁄8 9 1⁄2 F 820 865
13 37 1⁄2 27 47 5⁄8 9 1⁄2 F 920 970
14 37 1⁄2 27 52 5⁄8 9 1⁄2 F 1020 1070
15 37 1⁄2 27 57 5⁄8 9 1⁄2 F 1120 1175
* These parts furnished with only 2 mounting locations.
Refer to Front View ‘‘E’’.
Insulation Class: 600 volts (max).

Fig. 23. Dimensions and weights of DS300B 600-volt (maximum) resistors (open or with bolt-on covers)

Outlines: open frame

with covers (7.5KV)

Dimension Max. Weight

Part in Inches Front (Lb)
No. View Open With
Width B Height D Frame Covers
1† . . . . . . 23 7⁄8 21 3⁄4 E 185 200
2† . . . . . . 28 7⁄8 9 1⁄2 E 215 230
3† . . . . . . 33 ⁄8 9 ⁄2 E
7 1 245 260
4† . . . . . . 38 ⁄8 9 ⁄2 E
7 1 275 290
5 22 ⁄2 18 ⁄2 28 ⁄8 9 ⁄2 F
1 1 7 1 330 350
6 22 ⁄2 18 ⁄2 33 ⁄8 9 ⁄2 F
1 1 7 1 385 415
7 22 ⁄2 18 ⁄2 38 ⁄8 9 ⁄2 F
1 1 7 1 440 460
8 22 ⁄2 18 ⁄2 43 ⁄8 9 ⁄2 F
1 1 7 1 500 520
9 37 ⁄2 33 ⁄2 33 ⁄8 9 ⁄2 F
1 1 7 1 580 600
10 37 ⁄2 33 ⁄2 38 ⁄8 9 ⁄2 F
1 1 7 1 680 700
11 37 ⁄2 33 ⁄2 43 ⁄8 9 ⁄2 F
1 1 7 1 780 805
RESISTORS
12 37 ⁄2 33 ⁄2 48 ⁄8 9 ⁄2 F
1 1 7 1 880 905
13 37 ⁄2 33 ⁄2 53 ⁄8 9 ⁄2 F
1 1 7 1 980 1010
14 37 ⁄2 33 ⁄2 58 ⁄8 9 ⁄2 F 1080 1125
1 1 7 1

15 37 ⁄2 33 ⁄2 63 ⁄8 9 ⁄2 F 1185 1225
1 1 7 1

† These parts furnished with only 2 support insulators.

Refer to front view ‘‘E’’.
Insulation class: 7.5 kV (max).

Fig. 24. Dimensions and weights of DS300C 7.5 kV single-frame resistors (open or with bolt-on covers)

Data subject to change without notice

 6-14 Neutral Grounding Resistors

Type DS300C Stainless-steel Neutral Ground Resistors

DIMENSIONS (For Estimating Only)

All dimensions in inches.
RESISTORS

Outlines: 273A4728 - open frame (7.5KV) Outlines: 273A4729 - open frame (15KV)
273A4736 - with covers 273A4737 - with covers
Dimensions in Inches Max. Weight (Lb)* Dimensions in Inches Max. Weight (Lb)*
Part. Part.
No. Width Open With No. Open With
B Height D E F Width B Height D E F
Frame Covers Frame Covers
5 22 ⁄12 18 ⁄12 55 6 ⁄
14 13 ⁄
15 16 3 ⁄
58 620 650 105 22 ⁄2 18 ⁄2
1 1 57 ⁄2 8 ⁄4 16 7⁄16
1 3 4 1⁄8 665 695
6 22 1⁄2 18 1⁄2 65 6 1⁄4 13 15⁄16 3 5⁄8 730 760 106 22 1⁄2 18 1⁄2 67 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 775 805
7 22 1⁄2 18 1⁄2 75 6 1⁄4 13 15⁄16 3 5⁄8 840 910 107 22 1⁄2 18 1⁄2 77 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 885 915
8 22 1⁄2 18 1⁄2 85 6 1⁄4 13 15⁄16 3 5⁄8 960 1030 108 22 1⁄2 18 1⁄2 87 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 1000 1035
9 37 1⁄2 33 1⁄2 65 6 1⁄4 13 15⁄16 3 5⁄8 1110 1190 109 37 1⁄2 33 1⁄2 67 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 1200 1235
10 37 1⁄2 33 1⁄2 75 6 1⁄4 13 15⁄16 3 5⁄8 1315 1395 110 37 1⁄2 33 1⁄2 77 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 1400 1440
11 37 1⁄2 33 1⁄2 85 6 1⁄4 13 15⁄16 3 5⁄8 1515 1595 111 37 1⁄2 33 1⁄2 87 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 1600 1640
12 37 1⁄2 33 1⁄2 95 6 1⁄4 13 15⁄16 3 5⁄8 1720 1810 112 37 1⁄2 33 1⁄2 97 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 1800 1845
13 37 1⁄2 33 1⁄2 105 6 1⁄4 13 15⁄16 3 5⁄8 1920 2010 113 37 1⁄2 33 1⁄2 107 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 2010 2060
14 37 1⁄2 33 1⁄2 115 6 1⁄4 13 15⁄16 3 5⁄8 2120 2220 114 37 1⁄2 33 1⁄2 117 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 2210 2260
15 37 1⁄2 33 1⁄2 125 6 1⁄4 13 15⁄16 3 5⁄8 2320 2430 115 37 1⁄2 33 1⁄2 127 1⁄2 8 3⁄4 16 7⁄16 4 1⁄8 2420 2520
Fig. 25. Dimensions and weights of IC300B two-frame (stacked) 7.5 kV and 15 kV resistors (open or with bolt-on covers)
* Weight of 2 frame stack

Data subject to change without notice

 Neutral Grounding Resistors 6-15

Type DS300C Stainless-steel Neutral Grounding Resistors

DIMENSIONS—DS310 SAFETY-SCREEN ENCLOSURE

Hot-dipped Galvanized Construction (A)
DImensions in Inches
Enclosure Max.
C
Part No. Weight
DS310 Width Height JKW-3, (Lb.)
JKW-5
4
A044 A144 54 54 12 3⁄8 15 3⁄4 200
A045 A145 68 54 12 3⁄8 15 3⁄4 225
A046 A146 68 64 12 ⁄8
3 15 ⁄4
3 250
A047 A147 68 80 12 ⁄8
3 15 ⁄4
3 300
A048 A148 68 100 12 ⁄8
3 15 ⁄4
3 350
A049 A149 68 120 12 ⁄8
3 15 ⁄4
3 425

Fig. 26. Dimensions of grounded safety-screen enclosure for one- or two-frame

(stacked) resistors (Fig. 27)

Enclosure Dimensions in Inches

Part No.
DS310
A or B B* D E F
11 15.5 27.5 52.5
044, 144
18.5 9.75 25.75 52.5
045, 145 33.5 9.75 24.75 66.5
DIMENSIONS—DS310 GALVANIZED-STEEL STAND 11 9.5 47.5 66.5
With Hot-dipped Galvanized Safety-screen Enclosure 046, 146 18.5 9.75 39.75 66.5
All dimensions in inches. 33.5 9.75 24.75 66.5
047, 147 33.5 9.75 24.75 66.5
18.5 9.75 39.75 66.5
048, 148
33.5 9.75 24.75 66.5
18.5 9.75 39.75 66.5
049, 149
33.5 9.75 24.75 66.5
* Refer to Figures 24 and 25. Refer to company for DS300B mounting
dimensions.

Dimensions in Inches

RESISTORS
Stand Maximum
Assembly
Assembly Height E Weight
Part Width C Enclosure (Lb.)
No. DS310 Height
JKW-3,
E K JKW-5 E K
4
E044, E144 102 150 54 48 54 12 3⁄8 15 3⁄4 550 730
K044, K144
E045, E145 102 150 68 62 54 12 3⁄8 15 3⁄4 585 765
K045, K145
E046, E146 112 160 68 62 64 12 3⁄8 15 3⁄4 610 790
K046, K146
E047, E147 128 176 68 62 80 12 3⁄8 15 3⁄4 660 840
K047, K147
E048, E148 148 196 68 62 100 12 3⁄8 15 3⁄4 710 890
K048, K148
E049, E149 168 216 68 62 120 12 3⁄8 15 3⁄4 760 940
Fig. 31. Dimensions of stand with grounded safety-screen enclosure for
K049, K149
one-frame resistors and two-frame (stacked) resistors

Data subject to change without notice

 Neutral Grounding Resistors 6-17

Type 85A Stainless-steel Neutral Grounding Resistors

Description
Catalog Number 85A — — — — — — —
‘ ‘ ‘ ‘ ‘ ‘ ‘
SYSTEM VOLTAGE L-N
1300 volts 13
2400 volts 24
4160 volts 41
6600 volts 66
7200 volts 72
8000 volts 80
9950 volts 100
TIME RATING
10 sec on time A
extended time E
continuous C
60 sec B
30 sec D
CURRENT RATING
50 amps 50
100 amps 100
200 amps 200
400 amps 400
500 amps 500
600 amps 600
800 amps 800
1000 amps 1000
1200 amps 1200
1600 amps 1600
2000 amps 2000
ENCLOSURE TYPE
Mill finish Mx
Painted finish Px
Hot dip galvanized finish Hx
Aluminum Ax
Stainless steel Sx
Standard enclosure xA
Std enclosure with 4 ft stand xE
Std enclosure with 6 ft stand xF
Std enclosure with 8 ft stand xG
BUSHINGS
top bushing and bottom hub (basic version) 1
top bushing and bottom hub (w/terminals) 2
top and bottom bushings w/terminals 4
bottom entrance and exit with hubs 3
special per specifications 9
CURRENT TRANSFORMERS
none NN
5kv CT Ax
8.5kv ct Bx
15kv ct Cx
100:5 xK
200:5 xM
300:5 xN
RESISTORS
400:5 xP
600:5 xQ
800:5 xR
1000:5 xS
1200:5 xT
heater, anti-condensation Hx
special per specification Yx
OTHER MODIFICATIONS
none none
Special Customer Nameplate 2
Special Customer Drawings 3

Data subject to change without notice

6-18 Neutral Grounding Resistors

Type 85A Stainless-steel Neutral Grounding Resistors

DIMENSIONS
Rating
CATALOG NUMBER without CT with CT
AMPS OHMS W D H W D H
1390 Volts line to neutral (2,400 volt system) 10 second rating
50 27.5 85A 13 A 50 MA 1NN 36 32 24 36 36 24
100 14 85A 13 A 100 MA 1NN 36 32 24 36 36 24
200 7 85A 13 A 200 MA 1NN 36 32 24 36 36 24
300 4.6 85A 13 A 300 MA 1NN 36 32 24 36 36 24
400 4 85A 13 A 400 MA 1NN 36 32 24 36 36 24
500 3 85A 13 A 500 MA 1NN 36 32 24 36 36 24
600 2.3 85A 13 A 600 MA 1NN 36 32 24 36 36 24
800 1.7 85A 13 A 800 MA 1NN 36 32 24 36 36 24
1000 1.4 85A 13 A 1000 MA 1NN 36 32 24 36 36 24
2400 Volts line to neutral (4,160 volt system) 10 second rating
50 48 85A 24 A 50 MA 1NN 36 32 32 36 36 32
100 24 85A 24 A 100 MA 1NN 36 32 32 36 36 32
200 12 85A 24 A 200 MA 1NN 36 32 32 36 36 32
300 8 85A 24 A 300 MA 1NN 36 32 32 36 36 32
400 6 85A 24 A 400 MA 1NN 36 32 32 36 36 32
500 5 85A 24 A 500 MA 1NN 36 32 32 36 36 32
600 4 85A 24 A 600 MA 1NN 36 32 32 36 36 32
800 3 85A 24 A 800 MA 1NN 36 32 32 36 36 32
1000 2.4 85A 24 A 1000 MA 1NN 36 32 32 36 36 32
1200 2 85A 24 A 1200 MA 1NN 36 32 32 36 36 32
4160 Volts line to neutral (7,200 volt system) 10 second rating
50 83.2 85A 41 A 50 MA 1NN 36 36 36 36 42 36
100 41.6 85A 41 A 100 MA 1NN 36 36 36 36 42 36
200 20.8 85A 41 A 200 MA 1NN 36 36 36 36 42 36
300 13.9 85A 41 A 300 MA 1NN 36 36 36 36 42 36
400 10.4 85A 41 A 400 MA 1NN 36 36 36 36 42 36
500 10.4 85A 41 A 500 MA 1NN 36 36 36 36 42 36
600 8.3 85A 41 A 600 MA 1NN 36 36 36 36 42 36
800 5.2 85A 41 A 800 MA 1NN 36 36 36 36 42 36
1000 4.2 85A 41 A 1000 MA 1NN 36 36 36 36 42 36
1200 3.5 85A 41 A 1200 MA 1NN 36 36 36 36 42 36
8000 Volts line to neutral (13,900 volt system) 10 second rating
50 160 85A 80 A 50 MA 1NN 42 42 60 42 52 60
100 80 85A 80 A 100 MA 1NN 42 42 60 42 52 60
200 40 85A 80 A 200 MA 1NN 42 42 60 42 52 60
300 27 85A 80 A 300 MA 1NN 42 42 60 42 52 60
400 20 85A 80 A 400 MA 1NN 42 42 60 42 52 60
500 16 85A 80 A 500 MA 1NN 42 42 60 42 52 60
600 13 85A 80 A 600 MA 1NN 42 42 60 42 52 60
800 10 85A 80 A 800 MA 1NN 42 42 60 42 52 60
1000 8 85A 80 A 1000 MA 1NN 42 42 60 42 52 60
1200 6.7 85A 80 A 1200 MA 1NN 42 42 60 42 52 60

Data subject to change without notice