Littelfuse Startco SE-330 Series User manual

3714 Kinnear Place Saskatoon, SK Canada S7P 0A6 Ph: [phone] Fx: [phone] www.littelfuse.com/relayscontrols
SE-330 MANUAL
NEUTRAL-GROUNDING-RESISTOR MONITOR
REVISION 9-A-112913
0.1
0.5 0.7 1.0
2.0
3.0
5.0
10.0
4
10
8
15 20
40
660
80
1002
1.0
1.2
1.4
1.6
1.8 2.0 2.2
2.4
2.6
2.8
3.0
SE-330NEUTRAL-GROUNDING-RESISTOR
MONITOR
0.2
0.3
0.4 CAL
RESET
GF TRIP TIME (s) PULSE PERIOD (s)
GF TRIP LEVEL
(% CT RATING)
LITTELFUSE STARTCO
TRIP
GROUND
FAULT
POWER
RELAY K1
DIAGNOSTIC
CALIBRATED
TRIP
RESISTOR
FAULT
60
170
130
200 340
800
100 1200
1700
200020
V TRIP LEVEL N
()
S5
20 K
Vx1
N
100 K
Vx5
N
ΩΩ
Copyright 2013 Littelfuse Startco
All rights reserved.
Publication: SE-330-M
Document: S95-C330-00000
Printed in Canada.

Page i
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
TABLE OF CONTENTS
PAGE
1. General ................................................................... 1
1.1 Modern Resistance-Grounded Systems ................... 1
1.2 SE-330 NGR Monitoring......................................... 1
2. Operation................................................................ 2
2.1 Settings .................................................................... 2
2.1.1 GF Trip Time................................................ 2
2.1.2 GF Trip Level ............................................... 2
2.1.3 VNTrip Level ............................................... 2
2.1.4 Pulse-Period Adjustment .............................. 3
2.1.5 Configuration Settings.................................. 3
2.1.5.1 Relay K1 Function (S1) ................... 4
2.1.5.2 Trip-Relay Mode and
Trip Memory Mode(S2) ............................... 4
2.1.5.3 Ground-Fault-Trip Latch (S3).......... 4
2.1.5.4 Resistor-Fault-Trip Latch (S4)......... 4
2.1.5.5 Sensing-Resistor Selection (S5)....... 4
2.1.5.6 Frequency (S6)................................. 4
2.1.5.7 Spare (S7) ........................................ 4
2.1.5.8 Upgrade Enable (S8)........................ 4
2.2 Calibration ............................................................... 4
2.3 Pulsing Operation .................................................... 4
2.4 Trip Indication and Reset......................................... 5
2.5 Remote Operation.................................................... 5
2.6 Relay K1 LED ......................................................... 5
2.7 Unit Healthy Output ................................................ 5
2.8 Diagnostic LED ....................................................... 5
2.9 Analog Output ......................................................... 6
3. Installation.............................................................. 6
3.1 SE-330 ..................................................................... 6
3.2 Sensing Resistor..................................................... 12
3.3 Ground-Fault CT ................................................... 20
3.4 Isolated Ground Connection .................................. 24
3.5 Pulsing Connection................................................ 25
4. Communications.................................................. 25
4.1 Local Communications Port .................................. 25
4.1.1 Local Data Acquisition ............................... 25
4.1.2 Local Communications Commands............ 25
4.1.3 Firmware Upgrade ...................................... 25
4.2 Network Communications ..................................... 25
5. Troubleshooting................................................... 26
6. Technical Specifications...................................... 27
6.1 SE-330 ................................................................... 27
6.2 Sensing Resistors................................................... 28
6.3 Current Sensors...................................................... 29
7. Ordering Information ......................................... 29
PAGE
8 Warranty...............................................................30
9 Test Procedures ....................................................31
9.1 Resistor-Fault Tests................................................31
9.1.1 Calibration and Open Test..........................31
9.1.2 Voltage Test ...............................................31
9.2 Sensing-Resistor Test .............................................31
9.3 Analog-Output Test................................................31
9.4 Ground-Fault Performance Test .............................32
LIST OF FIGURES
FIGURE PAGE
1 Configuration Switches ............................................3
2 Analog-Output Connections.....................................6
3 SE-330 Connection Diagram....................................7
4 SE-330 Outline and Panel-Mounting Details ...........8
5 SE-330 Outline and Surface-Mounting Details........9
6 SE-IP65CVR-G Weatherproof Cover Outline .......10
7 SE-IP65CVR-G Weatherproof Cover Installation .11
8 ER-600VC Sensing Resistor ..................................12
9 SE-MRE-600 Moisture-Resistant Enclosure Outline13
10 SE-MRE-600 with installed ER-600VC...................14
11 ER-5KV Sensing Resistor ......................................15
12 ER-5WP Sensing Resistor......................................16
13 ER-15KV Sensing Resistor ....................................17
14 ER-25KV Sensing Resistor ....................................18
15 ER-35KV Sensing Resistor ....................................19
16 EFCT-1 Ground-Fault Current Sensor ...................21
17 SE-CS30-70 Ground-Fault Current Sensor ............22
18 EFCT-26 and SE-CS30-26 Ground-
Fault Current Sensors .........................................23
19 RK-332 Remote Indication and Reset ....................24
20 Simplified Isolated-Ground Connection.................24
21 Simplified Pulsing Connection...............................25
22 Ground-Fault-Test Circuits ....................................33
LIST OF TABLES
TABLE PAGE
1 Typical Values for Tripping Systems.......................3
2 Ground-Fault Trip Levels for Selected CT’s............3
3 RS-232 DB-9 Terminals.........................................25
4 Ground-Fault-Test Record......................................33
DISCLAIMER
Specifications are subject to change without notice.
Littelfuse Startco is not liable for contingent or
consequential damages, or for expenses sustained as a result
of incorrect application, incorrect adjustment, or a
malfunction.

Page 1
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
1. GENERAL
1.1 MODERN RESISTANCE-GROUNDED SYSTEMS
A high-resistance-grounded system uses a neutral-
grounding resistor (NGR) with a low let-through current
to limit ground-fault current. This is an improvement
over low-resistance or solidly-grounded systems because,
in those systems, a ground-fault flash hazard exists and a
ground fault can result in substantial point-of-fault
damage. High-resistance grounding eliminates these
problems and modern ground-fault protection operates
reliably at low current levels. Furthermore, the
probability of an arc-flash incident is significantly
reduced in a high-resistance-grounded system.
NGR selection depends on system charging current and
whether the system is an alarm-only or a tripping system.
Alarm-only systems are usually restricted to system
voltages up to 5 kV with NGR let-through currents of 5 A
or less. Occasionally, alarm-only systems up to 15 kV
and up to 10 A are used; however, they are not common
because a ground fault on such a system tends to escalate
to a phase-to-phase fault before the ground fault can be
located and cleared.
System charging current is the capacitive current that
flows to ground when a bolted ground fault occurs. This
current can be calculated or measured. For small systems,
the magnitude of charging current can be conservatively
estimated as ½ A per 1,000 kVA on low-voltage systems
and 1 A per 1,000 kVA on medium-voltage systems.
In an alarm-only system or in a tripping system without
selective coordination, choose an NGR with a let-through
current larger than the system charging current and set the
pick-up current of ground-fault devices at or below 50%
of the NGR let-through current.
In a tripping system with selective coordination, use
ground-fault devices with a definite-time characteristic to
achieve time coordination. Use the same pick-up current
for all ground-fault devices—this value must be larger
than the charging current of the largest feeder. Select an
NGR with a let-through current between five and ten
times the pick-up current of the ground-fault devices.
Do not use a grounding transformer with a low-voltage
resistor:
The combined cost of a transformer and a low-
voltage resistor is more than the cost of a resistor
rated for line-to-neutral voltage.
A transformer saturated by a ground fault through a
rectifier can make ground-fault protection
inoperative.
Transformer inrush current up to twelve times rated
current can cause a ground-fault voltage larger than
expected.
A parallel transformer winding makes it difficult to
monitor NGR continuity.
A transformer can provide the inductance necessary
to cause ferroresonance if the NGR opens.
Following these guidelines will reduce the flash hazard,
reduce point-of-fault damage, achieve reliable ground-
fault protection, and ensure a stable system not subject to
ferroresonance.
1.2 SE-330 NGR MONITORING
The SE-330 is a microprocessor-based neutral-
grounding-resistor monitor that detects NGR failures and
ground faults in resistance-grounded systems. The
SE-330 measures NGR resistance, NGR current, and
transformer or generator neutral-to-ground voltage. The
components required to monitor an NGR are an SE-330, a
20- or 100-kER-series sensing resistor, and a current
transformer (CT).
Power-circuit elements, other than neutral-connected
NGR’s, that purposefully connect the power system to
ground are often not compatible with SE-330 NGR
monitoring. These elements include single-phase
grounding transformers, grounded-wye-primary PT’s, and
grounded-wye-primary power transformers.
The SE-330 continuously measures NGR resistance in
an unfaulted system, and it will trip on resistor fault if
NGR resistance varies from its calibrated value. When a
ground fault occurs, voltage is present on the neutral and
NGR current will flow if the NGR is healthy. The
SE-330 will trip on ground fault if fault current exceeds
the GF TRIP LEVEL setting for an interval equal to the
GF TRIP TIME setting. However, if the NGR fails open
during a ground fault, it is possible for fault resistance to
satisfy the NGR resistance measurement. To detect this
double-fault condition, the SE-330 measures neutral
voltage. If neutral voltage exceeds the VNTRIP LEVEL
setting, and if NGR current is less than 5% of the CT
rating, the SE-330 will trip on resistor fault. If the
resistor-fault circuit is tripped and the neutral voltage
exceeds the VNTRIP LEVEL setting for an interval
greater than the GF TRIP TIME setting, the ground-fault
circuit will also trip.
Ground-fault current is sensed by a CT with a 1- or 5-A
secondary, or by a sensitive CT (EFCT-x or
SE-CS30-x) with a 50-mA secondary. The trip level of
the ground-fault circuit is adjustable from 2 to 100% of
the CT rating and trip time is adjustable from 0.1 to 10.0
seconds.
The SE-330 has four output relays. Relay K1 can be
assigned a trip or a pulsing function. Relays K2 and K3
provide ground-fault and resistor-fault indication. K4 is a
solid-state relay that provides UNIT HEALTHY
indication. When relay K1 is assigned the trip function, it
will operate on either a resistor fault or ground fault, and
it can be set to operate in the fail-safe or non-fail-safe
mode for undervoltage or shunt-trip applications. When
the pulsing function is selected, relay K1 is used to
control a contactor to assist in fault location.

Page 2
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
Additional features include LED trip indication, trip
memory, front-panel and remote reset, 4–20-mA analog
output, RS-232 local communications, data logging, and
optional network communications.
The SE-330 provides additional features and improved
performance over the SE-325 NGR Monitor:
SE-330 dc rejection is sufficient for reliable operation
in overhead-line applications.
Digital filtering of voltage and current signals
minimizes false trips due to harmonics.
Resistance measurement is calibrated to the NGR to
achieve a lower trip resistance.
Broader setting ranges.
Independent ground-fault and resistor-fault relays can
be used for indication and control.
Universal power supply.
Wider CT-selection range.
Network communications options provide
information to a distributed control system.
4–20 mA analog output.
UNIT HEALTHY output contact.
Power-up trip memory.
Pulsing capability can be used on low- and medium-
voltage systems to assist in locating ground faults.
RS-232 local communications port for firmware
upgrades and access to SE-330 measured parameters.
2. OPERATION
2.1 SETTINGS
2.1.1 GF TRIP TIME
GF TRIP TIME (definite time) is adjustable from 0.1 to
10.0 seconds. Time-coordinated ground-fault protection
requires this setting to be longer than the trip times of
downstream ground-fault devices.
A trip-time accumulator provides a ground-fault memory
function for detection of intermittent faults. The
accumulated time increases when a ground fault is detected
and decreases when a ground fault is not detected. A trip
will eventually occur when the time for fault current above
the trip level is greater than the time for fault current below
the trip level.
2.1.2 GF TRIP LEVEL
The SE-330 uses a Discrete-Fourier Transform (DFT)
algorithm to measure the fundamental component of NGR
current.
Choose an NGR let-through current and a ground-fault
trip level according to the guidelines in Section 1.1. Set the
ground-fault trip level as a percentage (2, 4, 6, 8, 10, 15, 20,
40, 60, 80, or 100) of the CT-primary rating. Inputs are
provided for 5-, 1-, and 0.05-A-secondary CT’s. Typical
values for 5-, 15-, and 25-A tripping systems are shown in
Table 1. Ground-fault trip levels for selected CT’s are
shown in Table 2. For other systems, refer to the NGR
Monitor Set-Point Assistant at
www.littelfuse.com/protectionrelays.
2.1.3 VNTRIP LEVEL
The SE-330 uses a DFT algorithm to measure the
fundamental component of neutral voltage.
Calculate the voltage across the NGR when NGR current
is equal to the pick-up current of the ground-fault circuit.
Set the VNTRIP LEVEL at the next largest value. The VN
TRIP LEVEL range is 20 to 2,000 V with switch S5 in the
20-k(Vx1) position, and the range is 100 to 10,000 V
with switch S5 in the 100-k(Vx5) position. See Fig. 1
and Section 2.1.5.5.
If neutral voltage is greater than the VNTRIP LEVEL
setting for 12 seconds and ground-fault current is less than
5% of the CT rating, the SE-330 will trip on resistor fault. If
the resistor-fault circuit is tripped and the neutral voltage
exceeds the VNTRIP LEVEL setting for an interval greater
than the GF TRIP TIME setting, the ground-fault circuit
will also trip.
Typical values for 5-, 15-, and 25-A tripping systems are
shown in Table 1. For an NGR resistance greater than 2
k, use a 100-ksensing resistor. For other systems, refer
to the NGR Monitor Set-Point Assistant at
www.littelfuse.com/protectionrelays.
NOTE:A resistor-fault trip is held off if the ground-fault
current is above 5% of the CT rating.

Page 3
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
TABLE 1. TYPICAL VALUES FOR TRIPPING SYSTEMS
System
Voltage
Neutral-Grounding
Resistor
Sensing
Resistor Ground-Fault Trip Level
VNTrip
Level
(Volts)
Current
(Amperes) Resistance (Ohms) Model Resistance (Switch S5 Setting) (Amperes) (Volts)
480
600
2,400
4,160
480
600
2,400
4,160
7,200
14,400
4,160
7,200
14,400
25,000
35,000
5
5
5
5
15
15
15
15
15
15
25
25
25
25
25
55
69
277
480
18
23
92
160
277
554
96
166
332
577
808
ER-600VC
ER-600VC
ER-5KV
ER-5KV
ER-600VC
ER-600VC
ER-5KV
ER-5KV
ER-15KV
ER-15KV
ER-5KV
ER-15KV
ER-15KV
ER-25KV
ER-35KV
20 k

20 k
20 k
20 k
20 k
20 k
20 k
20 k
100 k
100 k
20 k
100 k
100 k
100 k
100 k
1.0
1.0
1.0
1.0
3.0
3.0
3.0
3.0
3.0
3.0
5.0
5.0
5.0
5.0
5.0
60
100
340
800
60
100
340
800
170x5=850
340x5=1,700
800
170x5=850
340x5=1,700
800x5=4,000
1,200x5=6,000
TABLE 2. GROUND-FAULT TRIP LEVELS FOR SELECTED CT’S
GF TRIP
LEVEL
(%)
EFCT-x
5:0.05
(Amperes)
SE-CS30-x
30:0.05
(Amperes)
50:1
50:5
(Amperes)
100:1
100:5
(Amperes)
200:1
200:5
(Amperes)
400:1
400:5
(Amperes)
2
4
6
8
10
15
20
40
60
80
100
0.10
0.20
0.30
0.40
0.50
0.75
1.00
2.00
3.00
4.00
5.00
0.60
1.20
1.80
2.40
3.00
4.50
6.00
12.0
18.0
24.0
30.0
*
*
*
*
5
7.5
10
20
30
40
50
*
*
*
8
10
15
20
40
60
80
100
*
*
12
16
20
30
40
80
120
160
200
*
16
24
36
40
60
80
160
240
320
400
* Setting not recommended.
2.1.4 PULSE-PERIOD ADJUSTMENT
Pulse period is the cycle time of relay K1 when the
SE-330 is configured for pulsing operation. Pulse period
is adjustable from 1.0 to 3.0 seconds with a fixed duty
cycle of 50%. For example, with the 1.0-s setting, relay
K1 will alternately be energized for 0.5 seconds and de-
energized for 0.5 seconds when pulsing is enabled.
NOTE:For pulsing configuration, set switch S1 to K1 =
PULSING and install an external pulse-enable switch.
2.1.5 CONFIGURATION SETTINGS
Eight configuration switches (S1 to S8) and a
calibration push button are located behind the access
cover on the front panel. See Fig. 1.
CALBIRATION PUSH BUTTON
K1 =TRIP
FAIL-SAFE
LATCHING GF TRIP
LATCHING RF TRIP
20 kΩ
50 Hz
SPARE
RUN
NOTE: DEFAULT SETTINGS SHOWN.
S8
S7
S6
S5
S4
S3
S2
S1 K1 = PULSING
NON-FAIL-SAFE
NON-LATCHING GF TRIP
NON-LATCHING RF TRIP
100 kΩ
60 Hz
UPGRADE
FIGURE 1. Configuration Switches.

Page 4
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
2.1.5.1 RELAY K1 FUNCTION (S1)
Set switch S1 to K1 = TRIP to assign the trip function
to relay K1 and to activate switch S2. Relay K1 will
change state when a resistor-fault or ground-fault trip
occurs.
Set switch S1 to K1 = PULSING to configure relay K1
for pulsing operation. See Section 2.3.
2.1.5.2 TRIP-RELAY MODE AND TRIP MEMORY
MODE (S2)
Set switch S2 to select the operating mode of trip relay
K1. In the non-fail-safe mode, relay K1 energizes and its
contact closes when a trip occurs. The non-fail-safe mode
can be used to trip shunt-trip circuit breakers. In the non-
fail-safe mode, SE-330 trips are reset when supply
voltage is cycled.
In the fail-safe mode, relay K1 energizes and its contact
closes if there are no trips. Contacts open if there is a trip,
a loss of supply voltage, or a processor failure. In the fail-
safe mode, SE-330 trips are not reset when supply voltage
is cycled.
NOTE:Switch S2 does not affect the operating modes of
relays K2, K3, and K4.
NOTE:Switch S2 only affects relay K1 operating mode
when K1 is assigned the trip function (switch S1 set to K1
= TRIP). Switch S2 defines SE-330 trip memory
regardless of the switch S1 setting.
2.1.5.3 GROUND-FAULT-TRIP LATCH (S3)
Set switch S3 to select latching or non-latching ground-
fault-circuit operation. Non-latching operation defeats
ground-fault-trip memory. See Sections 2.1.5.2 and 2.4.
2.1.5.4 RESISTOR-FAULT-TRIP LATCH (S4)
Set switch S4 to select latching or non-latching
resistor-fault-circuit operation. Non-latching operation
defeats resistor-fault-trip memory. See Sections 2.1.5.2
and 2.4
2.1.5.5 SENSING-RESISTOR SELECTION (S5)
Set switch S5 to the resistance of the sensing resistor. For
the ER-600VC and ER-5KV, select 20 k. For the
ER-15KV, ER-25KV, and ER-35KV, select 100 k.
Switch S5 sets the resistor-fault trip value and the VNTRIP
LEVEL range. See Section 2.1.3.
2.1.5.6 FREQUENCY (S6)
Set switch S6 to 50 or 60 Hz to tune the digital filter to
the line frequency of the monitored system.
2.1.5.7 SPARE (S7)
2.1.5.8 UPGRADE ENABLE (S8)
Set switch S8 to RUN for normal operation or to
UPGRADE to enable firmware upgrades. Changes in
switch S8 settings are recognized only when supply
voltage is cycled. Protection is disabled after supply
voltage is cycled with S8 in the UPGRADE position. See
Section 4.1.3.
2.2 CALIBRATION
The SE-330 measures the resistance change of the
NGR relative to the NGR-resistance value determined at
the time of calibration. Calibrate the SE-330 on new
installations, if the NGR is changed, or if the sensing
resistor is changed.
NOTE:If the SE-330 is not calibrated and is supplied
from the load side of the breaker (non-fail-safe mode),
calibrate within 12 seconds of power-up or it may trip and
interrupt its supply.
The CALIBRATION push button is located behind the
access cover on the front panel, and it is recessed to
prevent inadvertent activation.
NOTE:Calibration must be performed with the SE-330
connected to the sensing resistor and NGR of the installed
system.
To calibrate, press and hold the CALIBRATION push
button until the green CALIBRATED LED turns off and
returns to on (if the LED is already off, press and hold
until the LED turns on). Calibration takes approximately
two seconds. If calibration is not successful, a resistor-
fault trip occurs, the RESISTOR FAULT TRIP LED will
be on, the CALIBRATED LED will be off, and the
DIAGNOSTIC LED will flash the calibration-error code.
See Section 2.8.
If latching resistor fault (switch S4) is selected, the
calibration-error code flashes until RESET is pressed
even if the CALIBRATED LED is on.
The calibration value is stored in non-volatile memory.
2.3 PULSING OPERATION
If switch S1 is set to K1 = PULSING, pulsing occurs
when terminal 16 is connected to terminal 17. Relay K1
operates at a 50% duty cycle and cycle time is adjustable
from 1.0 to 3.0 seconds. When terminals 16 and 17 are
not connected, K1 is not energized and its contact is open.
Relay K1 can be used to control a contactor rated for
use at the line-to-neutral voltage. The contactor causes
changes in neutral-to-ground resistance by adding or
shorting portions of the NGR. See Section 3.5. Pulsing
ground-fault current appears as zero-sequence current
upstream from the fault.
Pulsing ground-fault current is distinguishable from
charging current and noise, and it can be traced with a
clip-on ammeter or current probe. If pulsing current is
detected on a cable or conduit, the fault is downstream.
Systematic testing allows faults to be located without
isolating feeders or interrupting loads. If the fault is on a
conduit system with a complex mix of cables and ground
points, the exact location of the ground fault may be
difficult to determine.
Stop pulsing when the fault is located.

Page 5
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
2.4 TRIP INDICATION AND RESET
Red LED's and indication relays indicate ground-fault
and resistor-fault trips—indication relays K2 and K3 are
energized on trip. When a trip occurs with latching
operation selected, the SE-330 remains tripped until reset.
See Sections 2.1.5.3 and 2.1.5.4. Terminals 15 and 16 are
provided for remote reset as shown in Fig. 3. The reset
circuit responds only to a momentary closure so that a
jammed or shorted switch does not prevent a trip. The
front-panel RESET switch is inoperative when terminal
15 is connected to terminal 16. If non-latching operation
is selected, trips and corresponding indication
automatically reset when the fault clears and power-up
trip memory is defeated even when configuration switch
S2 is set to fail-safe. Automatic reset time is 2.8 s,
maximum.
The red DIAGNOSTIC LED annunciates latched
calibration-error and remote trips. See Section 2.8.
When supply voltage is applied with switch S2 set to
FAIL-SAFE, the SE-330 returns to its state prior to loss
of supply voltage unless switch S3 or S4 is set to non-
latching. When supply voltage is applied with
switch S2 set to NON-FAIL-SAFE, SE-330 trips are
reset. When a local, remote, or network reset is issued,
both trip LED's will flash if they are off.
Resistor-fault-trip reset can take up to one second.
Resistor-fault trip-memory trip can take up to three
seconds after SE-330 power up.
2.5 REMOTE OPERATION
Relays K2 and K3 can be used for remote indication,
and terminals 15 and 16 are provided for remote reset.
RK-332 Remote Indication and Reset components are
shown in Fig. 19. Connect them as shown in Fig. 3.
RK-332 components are not polarity sensitive.
Network-enabled SE-330’s can be remotely tripped and
reset by the network master. The red DIAGNOSTIC
LED indicates a network-initiated trip. See Section 2.8.
Refer to the appropriate SE-330 communications manual.
2.6 RELAY K1 LED
The yellow RELAY K1 LED follows the state of relay
K1 and is on when K1 is energized (contact closed).
2.7 UNIT HEALTHY OUTPUT
UNIT HEALTHY relay K4 is energized when the
processor is operating. It can be ordered with N.O. or
N.C. contacts. See Section 7.
NOTE:The K4 output changes state momentarily during
a processor reset.
NOTE:K4-contact rating is 100 mA maximum.
2.8 DIAGNOSTIC LED
The DIAGNOSTIC LED is used to annunciate trips
without individual LED indication. The number of short
LED pulses between pauses indicates the cause of the trip.
Calibration-Error Trip (1 short):
The calibration resistance of the NGR is outside the
calibration range. See Section 6.1.
Remote Trip (2 short):
The SE-330 has been tripped by a remote-trip
command from the communications interface.
EEPROM-Error Trip (3 short):
An EEPROM error has been detected.
A/D-Converter-Error Trip (4 short):
An A/D-converter error has occurred.
Software-Interrupt Trip (5 short):
CPU reset was caused by a software interrupt.
Illegal-Opcode Trip (6 short):
CPU reset was caused by an illegal Opcode.
Watchdog Trip (7 short):
CPU reset was caused by the watchdog.
Clock-Failure Trip (8 short):
CPU reset was caused by an internal clock failure.
CPU Trip (9 short):
This code is displayed if the supply is cycled after one
of the previous four errors occurred.
Resistor-fault trips occur with all of the above trips.
Ground-fault trips occur with all of the above trips except
the calibration-error trip and the A/D-converter-error trip.
See Troubleshooting Section 5.

Page 6
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
2.9 ANALOG OUTPUT
An isolated 4–20-mA output indicates NGR current
with full-scale output corresponding to the CT rating. An
internal 24-Vdc supply allows the analog output to be
connected as a self-powered output. Power from an
external supply is required for loop-powered operation.
See Fig. 2.
+24V
+
-
0V
+24V
+
-
0V
18
19
20
21
18
19
20
21
LOOP
SUPPLY
+-
SELF-POWERED
LOOP POWERED
FIGURE 2. Analog-Output Connections.
3. INSTALLATION
3.1 SE-330
Outline and panel-cutout dimensions for the SE-330 are
shown in Fig. 4. To panel mount the SE-330, insert it
through the panel cutout and secure it with four 8-32
locknuts and flat washers (included).
If an optional SE-IP65CVR-G Hinged Cover is used,
follow the included installation instructions. See Figs 6
and 7.
All connections to the SE-330 are made with plug-in,
wire-clamping terminal blocks. Each plug-in terminal
block can be secured to the monitor by two captive screws
for reliable connections.
Outline dimensions and mounting details for surface
mounting the SE-330 are shown in Fig. 5. Fasten the
surface-mount adapter to the mounting surface and make
connections to the adapter terminal blocks. Follow Fig. 5
instructions to mount or remove the SE-330.
Ground terminal 7 (G) and connect terminal 6 (R) to
the sensing-resistor R terminal.
Use terminal 1 (L1) as the line terminal on ac systems,
or the positive terminal on dc systems. Use terminal 2
(L2/N) as the neutral terminal on ac systems or the
negative terminal on dc systems. Connect terminal 3 ( )
to ground. Connect terminal 4 (SPG) to terminal 5
(SPGA). Remove the terminal-4-to-5 connection for
dielectric-strength testing.
NOTE: When the terminal-4-to-5 connection is removed,
protective circuits inside the SE-330 are disconnected to
allow dielectric strength testing of a control panel without
having to disconnect wiring to the SE-330. Ensure that
the terminal-4-to-5 connection is replaced after testing.

Page 7
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
L1
C
+
NOTE 12
XXX:1 OR XXX:5
8910 11
S15C
SE-330
ALTERNATE CT
CONNECTIONS
TRANSFORMER
OR GENERATOR
NOTE 1 NEUTRAL
NOTE 2
EFCT-X
OR
SE-CS30-X
NOTES 11 & 12
NOTE 3
N
NGR
ER-SERIES
SENSING
RESISTOR
RG
NOTE 4
NOTE 5
N/- SUPPLY
8910
11
S15C
5 A
1 A
EFCT
L/+ SUPPLY 1
22
26
29
12
14
15
16
17
3
4
5
REMOTE
RESET
PULSE
ENABLE
OPTIONAL
NETWORK COM
NOTE 10
SE-330
SPGA
SPG
PULSE ENABLE
RESET
ANALOG OUTPUT
NC NOTE 7
UNIT HEALTHY
K4
RF
K3
GF
K2
K1
NOTE 6
R
G
L2/N
+24V
-
0V
DCD
DSR
CTS
RxD
TxD
6
7
2
23
24
25
27
28
13
18
19
20
21
1
6
8
5
2
3
RS232 COM
NOTE 9
SELF POWERED
4-20 mA
OUTPUT
NOTE 8
RESISTOR
FAULT
GROUND
FAULT
NOTE 13 & 14
NOTES:
1. USE SEPARATE LUGTO CONNECT SENSING-
RESISTORTERMINAL N TO NEUTRAL.
2. LOCATE THESE COMPONENTS NEAR
TRANSFORMER OR GENERATOR.
3. ALTERNATE SENSING-RESISTOR
TERMINAL-N CONNECTION.THE NEUTRAL
CONNECTION IS NOT MONITORED.
4. VOLTAGE BETWEEN SENSING-RESISTOR
TERMINALS R AND G IS LIMITEDTO 100 V BY
INTERNAL CLAMP.
5. SEE SECTION 3.4 FOR ISOLATED-RESISTOR
CONNECTION.
6. RELAY CONTACTS SHOWN WITH SE-330
DE-ENERGIZED.
7. OPTIONAL N.C. K4 AVAILABLE.
8. LOOP-POWERED CONNECTION USES
TERMINALS 19 AND 20 ONLY.
9. RS232 PIN 4 (DTR), PIN 7 (RTS) AND
PIN 9 (RI) NOT CONNECTED.
10. REFERTO APPROPIATE SE-330
COMMUNICATIONS INTERFACE MANUAL.
11. TWO-CONDUCTORTWISTED CABLE
REQUIRED. SHIELDED OR ARMOURED
RECOMMENDED.
12. CT CONNECTION IS NOT POLARITY
SENSITIVE.
13. CONNECT CONTACTS K1, K2, K3, AND K4
AS REQUIRED FOR PROTECTION,
INDICATION, AND CONTROL.
NOTE 14
14. EXTERNAL LIGHTS AND SWITCHES NOT
INCLUDED WITH SE-330.
FIGURE 3. SE-330 Connection Diagram.

Page 8
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
1
4
2
3
5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
L1
L2/N
SPG
SPGA
RSENSING
RESISTOR
G
S
1
55
A
1
A
E
F
C
T
C
6
7
10
8
11
9
12
13
14
15
16
17
18
19
20
21
UNIT
HEALTHY K4
NC
24V
0V
RESET
PULSE ENABLE
ANALOG OUTPUT
27
28
29
22
23
24
25
26
K3
K2
GROUND
FAULT
RESISTOR
FAULT
K1
ATTENTION
DISENGAGE CAPTIVE RETAINING
SCREWS BEFORE REMOVING
PLUG-IN TERMINAL BLOCKS
+
+
-
98.3
(3.87)
212.6
(8.37)
16.0
(0.63)
132.0
(5.20)
PANEL THICKNESS
1.6 (0.06)TO 4.8 (0.19)
185.4
(7.30)
FRONT VIEW SIDE VIEW REAR VIEW
NOTE 2
92.7
(3.65)
76.2
(3.00)
8.2
(0.32)
186.0 (7.32)
200.0
(7.87)
7. 0
(0.28)
R=4.8 (0.19)
MAXIMUM
4.75 (0.187) DIA
4 LOCATIONS
PANEL-MOUNT CUTOUT
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. SE-330 SHOWN WITHOUT SWITCH
ACCESS COVER.
0.1
0.5 0.7 1.0
2.0
3.0
5.0
10. 0
4
10
8
15 20
40
660
80
1002
1.0
1.2
1.4
1.6
1.8 2.0 2.2
2.4
2.6
2.8
3.0
SE-330NEUTRAL-GROUNDING-RESISTOR
MONITOR
0.2
0.3
0.4
CAL
RESET
GF TRIP TIME (s) PULSE PERIOD (s)
GF TRIP LEVEL
(% CT RATING)
LITTELFUSE STARTCO
TRIP
GROUND
FAULT
POWER
RELAY K1
DIAGNOSTIC
CALIBRATED
TRIP
RESISTOR
FAULT
60
170
130
200 340
800
100 1200
1700
200020
V TRIP LEVEL N
()
S5
20 K
Vx1
N
100 K
Vx5
N
8
7
6
5
4
3
2
1
ΩΩ
FIGURE 4. SE-330 Outline and Panel-Mounting Details.

Page 9
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
(NOTE 2)
REMOVAL
1 1
4 4
2 2
3 3
5 5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
L1
L2/N
SPG
SPGA
R
SENSING
RESISTOR G
S
1
5
5
A
1
A
E
F
C
T
C
6 6
7 7
10 10
8 8
11 11
9 9
12
13
14
15
16
17
18
19
20
21
UNIT
HEALTHY
K4
NC
24V
0V
RESET
PULSE ENABLE
ANALOG OUTPUT
27
28
29
22
23
24
25
26
K3
K2
GROUND
FAULT
RESISTOR
FAULT
K1
+
+
-
RETAINER SCREW
RETAINER
8.0
(0.31)
114.3
(4.50)
98.3
(3.87)
6.4
(0.25)
212.6
(8.37)
225.4 (8.87)
138.0
(5.43)
SIDE VIEWFRONT VIEW
FRONT VIEW
SE-330-SMA
25.4
(1.00)
63.5
(2.50)
5.0
(0.20)
215.9
(8.50)
BEZEL OUTLINE
ADAPTER PANEL OUTLINE
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M4 OR 8-32 PANHEAD.
INSTALLATION
1. LOOSEN RETAINER SCREWS, MOVE RETAINERS
OUTWARD AND TIGHTEN RETAINER SCREWS.
2. MATE MONITOR WITH ADAPTER PLUG-INTERMINALS.
LOOSEN RETAINER SCREWSTO LET RETAINERS
SNAP OVER MONITOR BACKPLATE.
3. ENSURETHAT RETAINERS ARE AGAINST MONITOR
BODY ANDTIGHTEN RETAINER SCREWS.
1. LOOSEN RETAINER SCREWS, SLIDE RETAINERS AWAY
FROM MONITOR BODY ANDTIGHTEN RETAINER SCREWS.
2. PULL MONITOR FORWARD.
0.1
0.5 0.7 1.0
2.0
3.0
5.0
10.0
4
10
8
15 20
40
660
80
1002
1.0
1.2
1.4
1.6
1.8 2.0 2.2
2.4
2.6
2.8
3.0
SE-330NEUTRAL-GROUNDING-RESISTOR
MONITOR
0.2
0.3
0.4 CAL
RESET
GF TRIP TIME (s) PULSE PERIOD (s)
GF TRIP LEVEL
(% CT RATING)
LITTELFUSE STARTCO
TRIP
GROUND
FAULT
POWER
RELAY K1
DIAGNOSTIC
CALIBRATED
TRIP
RESISTOR
FAULT
60
170
130
200 340
800
100 1200
1700
200020
V TRIP LEVELN
()
S5
20 K
Vx1N
100 K
Vx5
N
ΩΩ
FIGURE 5. SE-330 Outline and Surface-Mounting Details.

Page 10
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
HOLE FOR
SEAL WIRE
SHOWN
WITH
SEAL
TOP VIEW
FRONT VIEW SIDE VIEW
34.0
(1.34)
250.0
(9.84)
127.0
(5.00)
NOTES:
1. DIMENSIONS SHOWN IN MILLIMETRES (INCHES).
2. SHOWN WITH WEATHERPROOF SNAPS CLOSED.
3. REFERTO PANEL MOUNTING CUTOUT (FIGURE 4) FOR PANEL
MOUNTING DETAIL.
TO PREVENT UNAUTHORIZED ENTRY:
1. USE WIRE SEALTHROUGH HOLES IN
WEATHERPROOF COVER ASSEMBLY, OR
2. SECURE WITH THE PLASTICTHREAD FORMING
SCREW SUPPLIED IN KIT.
FIGURE 6. SE-IP65CVR-G Weatherproof Cover Outline

Page 11
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
INSTALL O-RING INTO
GROOVE INTHE REAR
OF WEATHERPROOF
WINDOW
INSERT MONITOR/RELAY THROUGH OPENING
OF THE WEATHERPROOF WINDOW, UNTIL IT
IS SECURELY NESTED TO THE BACK OF THE
DARK GREY PVC PANEL.
INSTALL O-RING INTOTHE GROOVE INTHE REAR
OF WEATHERPROOF WINDOW ASSEMBLY.
INSERT ASSEMBLY INTO PANEL AND FAST WITH
THE HARDWARE PROVIDED WITH MONITOR/RELAY.
FIGURE 7. SE-IP65CVR-G Weatherproof Cover Installation

Page 12
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
3.2 SENSING RESISTOR
Outline and mounting details for ER-600VC, ER-5KV,
ER-5WP, ER-15KV, ER-25KV, and ER-35KV sensing
resistors are shown in Figs.8, 11, 12, 13, 14, and 15.
Locate the NGR and the sensing resistor near the
transformer or generator. When located outdoors, a
sensing resistor must be installed in a suitable enclosure.
An optional SE-MRE-600 Moisture-Resistant Enclosure
is available for applications which may expose an ER-
600VC to moisture. See Figs. 9 and 10. The weather-
protected ER-5WP shown in Fig. 12 is an ER-5KV with
moisture-resistant terminal covers. Use an ER-5WP in
applications in which it might be exposed to moisture.
The ER-15KV, ER-25KV, and ER-35KV include
moisture-resistant terminal covers. Use suitable water-
tight fittings. Ground sensing-resistor terminal G. Pass the
sensing-resistor-to-neutral conductor and the NGR-to-
neutral conductor through the ground-fault-CT window as
shown in Fig. 3. Separately connect sensing-resistor
terminal N and the NGR to the neutral to include neutral
connections in the monitored loop. Alternately, if the
NGR connection to system neutral need not be monitored,
connect terminal N to the NGR neutral terminal.
If a ground fault in the sensing-resistor conductor is
unlikely, a minimal loss of protection will result if it does
not pass through the ground-fault-CT window. See Note 3
in Fig. 3.
CAUTION: Voltage at terminal N rises to line-to-neutral
voltage when a ground fault occurs. The same clearances
are required for sensing resistors as for NGR’s.
NOTE: A parallel ground path created by moisture can
result in a false resistor-fault trip. Sensing-resistor
terminal R and its connection to SE-330 terminal R,
including interposing terminal blocks, must remain dry.
NOTE: The neutral-to-sensing-resistor-terminal-N
connection is not a neutral conductor as defined in
Canadian Electrical Code Section 10-1108 and National
Electrical Code Section 250.36(B). It is not required to be
8 AWG or larger. Since current through this conductor is
always less than 250 mA, a 14 AWG conductor insulated
to the system voltage is more than sufficient.
.
.
.......
..........
..........
N
R
G
ER-600VC
SENSING RESISTOR
20 K Ω
600 VAC MAX
RATINGS:
MAXIMUM VOLTAGE 600 Vac
MAXIMUM CURRENT 30 mA
RESISTANCE 20 kΩ
THERMAL:
420 Vac CONTINUOUS
600 Vac 6 MINUTES ON,
60 MINUTES OFF
40.0
(1.57)
105.0
(4.13)
4.5 (0.18) DIA
C’BORE 10.0 (0.39) DIA
3.2 (0.13) DEEP
FRONT
41.5
(1.63)
22.2
(0.87)
8.0
(0.31)
10.5
(0.41)
40.0
(1.57)
19.0
(0.75)
10.5
(0.41)
NOTE 3
105.0
(4.13)
89.0
(3.50)
8.0
(0.31)
SIDE MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25.
3. MOUNTING SCREWS: M4 OR 8-32.
4. ON REVISION 2 UNITS ENCLOSURE IS ELECTRICALLY CONNECTEDTO
TERMINAL G THROUGH JUMPER FROM TERMINAL G TO SCREW.
THIS CONNECTION MAY BE REMOVED FOR DIELECTRIC STRENGTH
TESTING. ENSURETHAT THE JUMPER IS INSTALLED AFTER TESTING.
5. ON REVISION 1 UNITS, SCREW IS NOT PRESENT AND ENCLOSURE IS
ELECTRICALLY CONNECTEDTOTERMINAL G.
6. NOT ALL CERTIFICATIONS SHOWN.
LR 53428
US
C
R
Revision:
ER-600VC
ER-600VC
SENSING RESISTOR Serial No:
02
GC131105487
1-800-TEC-FUSE (1-800-832-3873) Made in Saskatoon, Canada
Rating: 600 Vac 50/60 Hz
30 mA Max
20 KΩ
Use with: SE-325, SE-330, SE-330AU
IEEE 32
Duty Cycle: 6 Minutes On, 60 Minutes Off
at 600 Vac
Continuous at 420 Vac
FIGURE 8. ER-600VC Sensing Resistor.

Page 13
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
COVER - INSIDE VIEW
GASKET
120.4
(4.74)
122.0
(4.80)
ENCLOSURE - SIDE VIEW
84.6
(3.33)
120.4
(4.74)
20.4
(0.80)
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M6 OR 0.25-20.
120.4
(4.74)
122.0
(4.80)
ENCLOSURE - TOP VIEW
ENCLOSURE - TOP VIEW
(COVER REMOVED)
122.0
(4.80)
120.4
(4.74)
MOUNTING DETAIL
9.5
(0.38)
82.5
(3.25)
19.1
(0.75)
82.5
(13.25)
M6 OR 0.25-20
FIGURE 9. SE-MRE-600 Moisture-Resistant Enclosure Outline.

Page 14
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
N
R
G
ER-600VC
SENSING RESISTOR
20 KΩ
600 VAC MAX
ENCLOSURE - TOP VIEW
WITH INSTALLED ER-600VC
(COVER REMOVED)
COVER - INSIDE VIEW
ASSEMBLY INSTRUCTIONS
1. DRILL HOLE FOR ENCLOSURE WIRE ENTRY. USE LIQUID-TIGHT
GLAND.
3. ATTACH GROUND WIRE FROM ENCLOSURETO COVER ANDTO
ER-600VC.
2. REMOVE NYLON NUTS AND WASHERS. INSERT ER-600VC INTO
ENCLOSURE. REPLACE NUTS AND WASHERS.
4. MOUNT SE-MRE-600 IN PLACE USING M6 OR 0.25 - 20.
5. COMPLETE OTHER WIRING AND REPLACE COVER.
NOTE 3
NOTE 2
NOTE 2
MOUNTING
SCREW
LOCATIONS
FIGURE 10. SE-MRE-600 with installed ER-600VC.

Page 15
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
GR
VOLTAGE ON THIS SURFACE RISES
TO LINE-TO-NEUTRAL VOLTAGE
WHEN A GROUND FAULT OCCURS
N
CAUTION
HIGH VOLTAGE
.
.
.......
..........
ER-5KV
SENSING RESI TORS
20 K Ω
2500 VAC MAX
RATINGS:
MAXIMUM VOLTAGE
MAXIMUM CURRENT
RESISTANCE
THERMAL CONTINUOUS
20 kΩ
125 mA
2,500 Vac
105.0
(4.13)
52.5
(2.07)
7. 9
(0.31)
12.0
(0.47)
21.0
(0.83)
381.0
(15.00)
ALTERNATE NEUTRAL CONNECTION
NEUTRAL CONNECTION
0.25-20 UNC
THREADED
INSERT
10-32THREADED
INSERT
TOP VIEW
316.0
(12.44)
0.25-20 UNC STUD
188.0 (7.40)
FRONT VIEW
NOTE 2
NOTES 5 & 6
SIDE VIEW
MINIMUM DISTANCE
TO ADJACENT OBJECTS
NOTE 3
MINIMUM CLEARANCE FROM BASE
254.0 (10.00)
127.0
(5.00)
254.0
(10.00)
355.6
(14.00)
457.0
(18.00)
50.7
(2.00)
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25.
3. MOUNTING SCREWS: M6 OR 0.25-20.
4. THIS DEVICE CAN DISSIPATE
300 WATTS.TO MINIMIZE SURFACE
TEMPERATURES FOR SYSTEMS
ALLOWEDTO OPERATE
CONTINUOUSLY WITH A GROUND
FAULT, MOUNT VERTICALLY WITH
R & GTERMINALS DOWN.
5. ON REVISION 2 UNITS BASE IS
ELECTRICALLY CONNECTEDTO
TERMINAL G THROUGH JUMPER
FROMTERMINAL G TO SCREW.
THIS CONNECTION MAY BE
REMOVED FOR DIELECTRIC
STRENGTH TESTING. ENSURE
THAT THE JUMPER IS INSTALLED
AFTER TESTING.
6. ON REVISION 0 & 1 UNITS SCREW
IS NOT PRESENT AND BASE IS
ELECTRICALLY CONNECTED TO
TERMINAL G.
7. CERTIFICATIONS NOT SHOWN.
.....
TORQUE
5.6 N-m (50 in-lb)
N
N
TERMINAL N (3 LOCATIONS)
10-32 INSERT
OTHERS .....9.0 N-m (80 in-lb)
...
.
FIGURE 11. ER-5KV Sensing Resistor.

Page 16
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
V O L T A G E O N T H I S S U R F A C E R I S E S
TO LINE-TO-NEUTRAL VOLTAGE
WHEN A GROUND FAULT OCCURS
N
CAUTION
HIGH VOLTAGE
ER-5WP
SENSING RESI TORS
20 K Ω
2500 VAC MAX
105.0
(4.13)
52.5
(2.07)
7. 9
(0.31)
12.0
(0.47)
21.0
(0.83)
381.0
(15.00)
ALTERNATE NEUTRAL CONNECTION
NEUTRAL CONNECTION
0.25-20 UNC
THREADED
INSERT
10-32THREADED
INSERT
TOP VIEW
316.0
(12.44)
0.25-20 UNC STUD
188.0 (7.40)
FRONT VIEW
SIDE VIEW
MINIMUM DISTANCE
TO ADJACENT OBJECTS
NOTE 3
MINIMUM CLEARANCE FROM BASE
254.0 (10.00)
127.0
(5.00)
254.0
(10.00)
355.6
(14.00)
457.0
(18.00)
50.7
(2.00)
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25
CABLE ACCESS OPENING IS 1/2 NPT.
USE A LIQUID-TIGHT FITTING FOR
CABLE ENTRY.
3. MOUNTING SCREWS: M6 OR 0.25-20.
4. THIS DEVICE CAN DISSIPATE
300 WATTS.TO MINIMIZE SURFACE
TEMPERATURES FOR SYSTEMS
ALLOWEDTO OPERATE
CONTINUOUSLY WITH A GROUND
FAULT, MOUNT VERTICALLY WITH
R & GTERMINALS DOWN.
5. BASE IS ELECTRICALLY CONNECTED
TOTERMINAL G THROUGH JUMPER
FROMTERMINAL GTO SCREW.
THIS CONNECTION MAY BE
REMOVED FOR DIELECTRIC
STRENGTH TESTING. ENSURETHAT
THE JUMPER IS INSTALLED AFTER
TESTING.
6. CERTIFICATIONS NOT SHOWN.
NOTE 2 AND 5
N
N
.
.
.......
..........
RATINGS:
MAXIMUM VOLTAGE
MAXIMUM CURRENT
RESISTANCE
THERMAL CONTINUOUS
20 kΩ
125 mA
2,500 Vac
.....
TORQUE
5.6 N-m (50 in-lb)
TERMINAL N (3 LOCATIONS)
10-32 INSERT
OTHERS
.....
9.0 N-m (80 in-lb)
...
.
FIGURE 12. ER-5WP Sensing Resistor.

Page 17
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
N
VOLTAGE AT TERMINAL N RISES
TO LINE-TO-NEUTRAL VOLTAGE
WHEN A GROUND FAULT OCCURS
CAUTION
HIGH VOLTAGE
..
.
.......
..........
R
G
ER-15 KV
SENSING RESISTOR
100 K Ω
8400 VA C MAX
1MINUTEMAX
144.0 (5.67)
NOTES 2 AND 4
422.0
(16.61)
132.0 (5.20)
20.5
(0.81)
0.25-20 BINDING HEAD
TOP
RATINGS:
MAXIMUM VOLTAGE 8,400 Vac
MAXIMUM CURRENT 84 mA
RESISTANCE .100 kΩ
THERMAL
1 MINUTE ON,
120 MINUTES
OFF
CONTINUOUS
215.0
(8.46)
FRONT SIDE
39.5
(1.56)
444.0
(17.50)
365.0
(14.37)
39.5
(1.56)
MINIMUM DISTANCE
TO ADJACENT OBJECTS
NOTE 3
MINIMUM CLEARANCE FROM BASE
305.0 (12.00)
90.0
(3.53)
100.0
(3.94)
90.0
(3.53)
280.0
(11.00)
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES
(INCHES).
2.TERMINAL-BLOCK SCREWS:
6-32 x 0.25.
3. MOUNTING SCREWS:
M6 OR 0.25-20.
4. USE LIQUID-TIGHT FITTING
FORTERMINAL-BLOCK-
ENCLOSURE CABLE ENTRY.
5. CERTIFICATIONS NOT SHOWN.
TORQUE
TERMINAL N ..... 9.0 N-m (80 in-lb)
.. .
8,400 Vac
1,900 Vac ..........
FIGURE 13. ER-15KV Sensing Resistor.

Page 18
SE-330 Neutral-Grounding-Resistor Monitor Rev. 9-A-112913
MINIMUM DISTANCE
TO ADJACENT OBJECTS
.
.
.......
R
G
CAUTION
HIGH VOLTAGE
N
VOLTAGE AT TERMINAL N RISES
TO LINE-TO-NEUTRAL VO LTAGE
WHEN A GROUND FAULT OCCURS
CAUTION
HIGH VOLTAGE
ER-25KV
SENSING RESISTOR
100 K Ω
14,400VAC MAX
1MINUTEMAX
144.0
(5.67)
NOTES 2 AND 4
20.5
(0.81)
0.25-20 BINDING HEAD
780.0
(30.70)
RATINGS:
MAXIMUM VOLTAGE 14,400 Vac
MAXIMUM CURRENT 144 mA
RESISTANCE 100 kΩ
TOP
320.0
(12.60)
FRONT SIDE
60.0
(2.40)
800.0
(31.50)
340.0
(13.38)
340.0
(13.38)
534.0
(21.00)
217.0
(8.50)
100.0
(3.94)
NOTE 3
MINIMUM CLEARANCE FROM BASE
508.0 (20.00)
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN
MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS:
6-32 x 0.25.
3. MOUNTING SCREWS:
M6 OR 0.25-20
4. USE LIQUID-TIGHT FITTING
FORTERMINAL-BLOCK-
ENCLOSURE CABLE ENTRY.
5. MOUNT AS SHOWN
WITH BASE HORIZONTAL.
6. CERTIFICATIONS NOT SHOWN.
TORQUE
TERMINAL N
.....
9.0 N-m (80 in-lb)
..
.........
THERMAL
1 MINUTE ON,
120 MINUTES
OFF
CONTINUOUS
14,400 Vac
2,500 Vac
.........
FIGURE 14. ER-25KV Sensing Resistor.