Littelfuse Startco EL731 User manual
EL731 MANUAL
AC/DC SENSITIVE
EARTH-LEAKAGE RELAY
REVISION 6-F-032816
Copyright © 2016 by Littelfuse Startco
All rights reserved.
Document Number: PM-1005-EN
Printed in Canada.
3714 Kinnear Place Saskatoon, SK Canada S7P 0A6 Ph: (306) 373-5505 Fx: (306) 374-2245 www.littelfuse.com/relayscontrols
Page i
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
Factory default password is 1111
New Password
See Section 3.2.4.
Page ii
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
TABLE OF CONTENTS
SECTION PAGE
1 Introduction.............................................................. 1
1.1 General........................................................................ 1
1.2 EL731 Features .......................................................... 1
1.2.1 Protective Functions....................................... 1
1.2.2 Metering.......................................................... 1
1.2.3 Data Logging.................................................. 1
1.2.4 Inputs and Outputs ......................................... 1
1.2.5 Operator Interface .......................................... 1
1.2.6 Communications Interface............................. 1
2 Installation................................................................. 1
2.1 System Wiring............................................................ 1
2.1.1 Supply Voltage............................................... 2
2.1.2 Current Sensor Connections .......................... 2
2.1.3 Analog Output ................................................ 2
2.1.4 PTC or RTD Input.......................................... 2
2.1.5 Communications (Optional) .......................... 2
2.1.6 Remote Reset.................................................. 2
2.1.7 Relay Outputs ................................................. 2
2.2 Calibration .................................................................. 2
3 Operation and Setup................................................ 9
3.1 Display and Indication ............................................... 9
3.1.1 Front-Panel LED Indication .......................... 9
3.1.1.1 Trip .................................................... 9
3.1.1.2 CT Status ........................................... 9
3.1.1.3 Alarm................................................. 9
3.1.2 Communications-Module LED
Indication and Status ...................................... 9
3.2 Main Menus................................................................ 9
3.2.1 Metering.......................................................... 9
3.2.2 Messages......................................................... 9
3.2.3 Setup .............................................................10
3.2.3.1 Earth-Fault Protection.....................10
3.2.3.2 Temperature Protection .................. 10
3.2.3.3 Output-Relay Assignments ............ 10
3.2.3.4 Analog Output.................................10
3.2.3.5 Miscellaneous Configuration .........11
3.2.3.5.1 Password ......................... 11
3.2.3.5.2 Reset Password ...............11
3.2.3.5.3 Menu Timeout ................11
3.2.3.5.4 Display Filter .................. 11
3.2.3.5.5 Maintenance....................11
3.2.4 Password.......................................................11
3.3 Trip Reset ................................................................. 11
4 Theory of Operation.............................................. 15
4.1 CT1 Theory of Operation ........................................ 15
4.2 CT2 Theory of Operation ........................................ 15
4.2.1 CT2 Full Range Filter .................................. 15
4.2.2 CT2 90 Hz Low Pass Filter .........................15
4.2.3 CT2 3 kHz Low Pass Filter .........................16
4.2.4 CT2 190 Hz High Pass Filter....................... 16
5 Personal Computer Interface...............................16
5.1 Flash Memory Upgrade ...........................................16
SECTION PAGE
6 Technical Specifications........................................ 16
6.1 EL731 ....................................................................... 16
6.2 EMC Tests................................................................ 17
6.3 Certification.............................................................. 18
6.4 Current Sensors ........................................................ 18
7 Ordering Information........................................... 19
8 Warranty................................................................. 19
9 Performance Test................................................... 20
10 Maintenance ........................................................... 20
Appendix A EL731 Menu Map........................................ 22
Appendix B System Parameters & Setup Record......... 24
Appendix C EL731 Revision History.............................. 25
LIST OF FIGURES
FIGURE PAGE
1 EL731 Outline and Mounting Details ........................... 3
2 AC700-SMK Outline and Mounting Details................ 4
3 Panel and Surface Mounting Connections .................... 4
4 Connection Diagram ...................................................... 5
5 AC700-CVR-00 Weatherproof Cover Outline............. 6
6 AC700-CVR-00 Weatherproof Cover Installation....... 7
7 EL731 with installed EtherNet/IP™
Communications Upgrade Adapter
(AC700-CUA-03).......................................................... 8
8 EL731 with Firmware Upgrade Module
(AC700-CUA-00). ........................................................ 8
9 EFCT-1 Outline and Mounting Details....................... 12
10 EFCT-2 Outline and Mounting Details....................... 13
11 EFCT-26 Outline and Mounting Details..................... 14
12 PGA-0520 Analog Percent Current Meter.................. 15
13 Earth-Fault-Test Circuit ............................................... 21
LIST OF TABLES
TABLE PAGE
1 Trip LED Flash Codes ................................................... 9
2 CT2 Input Filters .......................................................... 10
3 Output-Relay Functions ............................................... 10
4 Earth-Fault-Test Record............................................... 21
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 iii
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
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Page 1
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
1 INTRODUCTION
1.1 GENERAL
The EL731 is a microprocessor-based earth-leakage
relay for AC, DC, combined AC/DC, and variable-
frequency power circuits supplied by solidly or resistance-
earthed systems that require earth-leakage detection as
low as 30 mA (under default configuration). Earth-
leakage metering and two setting levels (alarm and trip)
are provided. It is uniquely suited for sensitive earth-fault
protection for adjustable-speed drive (ASD) circuits that
often operate at low speeds. A temperature-sensor input
provides metering and protection for a motor or ASD.
Settings and configuration selections provide
frequency-response ranges of 0 to 90 Hz, 20 to 90 Hz, 190
to 6,000 Hz, 20 to 6,000 Hz, 20 to 3,000 Hz and 0 to 6,000
Hz.
Three Form-C (changeover) output relays with
normally closed and normally open contacts can be
programmed for various functions and can be set to
operate in the fail-safe or
non-fail-safe modes for undervoltage or shunt-trip
applications.
Additional features include a 2 x 16-character OLED
alphanumeric display, current and temperature metering,
programming and menu-navigation push buttons,
password security, LED trip and alarm indication, auto-
reset alarms and latching trips with front-panel and remote
reset, trip memory, 4- to 20-mA analog output, CT
verification with LED indication, and conformal-coated
circuits.
Earth-leakage current is sensed by one or two EFCT-
series core-balance zero-sequence current transformers.
The alarm- and trip-level ranges of the earth-leakage
circuit are 30 to 5,000 mA. To modify this range,
firmware settings for each CT input allow configuring the
number of phase-conductor turns that are passed through
the CT-primary window – the lowest pickup configuration
is 6 to 1,000 mA, with a setting of five turns. With two
CT’s connected, the EL731 performs independent
metering. The trip-time delay has a definite-time
characteristic and is configurable from instantaneous to
two seconds in millisecond increments.
1.2 EL731 FEATURES
1.2.1 PROTECTIVE FUNCTIONS
AC earth overcurrent (50G/51G, 50N/51N)
DC earth overcurrent (76G)
PTC overtemperature (49)
RTD temperature (38, 49)
1.2.2 METERING
Earth-leakage current, CT1 and CT2
RTD temperature or PTC status
1.2.3 DATA LOGGING
Trip counters
Alarm counters
1.2.4 INPUTS AND OUTPUTS
AC earth-leakage current transformer (CT2)
AC/DC earth-leakage current transformer (CT1)
Remote reset input (one shot operation)
Network communications (optional)
4-20-mA analog output, programmable, loop powered
Temperature-sensor input, Pt100 RTD or PTC
Three output relays, programmable
1.2.5 OPERATOR INTERFACE
2 x 16 OLED alphanumeric display
Display-control and programming buttons
LED status indication
1.2.6 COMMUNICATIONS INTERFACE
The EL731 interface for optional network
communications adapters supports DeviceNet™,
Profibus®, EtherNet/IP®, and Modbus®TCP. Units
purchased without a communications adapter can be field-
upgraded.
An optional firmware upgrade module is available for
firmware upgrades.
For ordering information, see Section 7.
2. INSTALLATION
Outline and details for panel-mounting an EL731 are
shown in Fig. 1. Insert the EL731 through the cutout and
slip the panel-mount clamp over the EL731 body. Slide
the panel-mount clamp forward to engage the latch tabs
with the mating body retainer grooves. Lock the unit in
place by tightening the four clamp screws against the
panel.
NOTE:Do not over tighten the clamp screws as this might
deform the clamp and release the latch tabs. The
maximum recommended torque is 0.28 N·m (2.5 lbf·in).
Outline and details for surface-mounting the EL731 are
shown in Fig. 2. A detailed instruction sheet is included
with the optional AC700-SMK Surface-Mounting
Hardware Kit.
If an optional AC700-CVR-00 Weatherproof Cover is
used, follow the included installation instructions. See
Figs. 5 and 6.
2.1 SYSTEM WIRING
A typical connection diagram for the EL731 is shown
in Fig. 4 and terminal-layout diagrams are shown in
Fig. 3.
A minimum 75°C (167°F) wire-temperature rating is
required.
Page 2
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
2.1.1 SUPPLY VOLTAGE
Provide supply voltage from the line side of the
controller or from an independent source. Connect supply
voltage to terminals 14 and 15 (L1, L2/N) as shown in
Figs. 3 and 4. In 120-Vac systems, L2/N is designated as
the neutral conductor. For direct-current power supplies,
use L1 for the positive terminal and L2/N as the negative
terminal. Connect terminal 16 ( ) to earth.
2.1.2 CURRENT SENSOR CONNECTIONS
This earth-leakage relaying system consists of an
EL731 earth-leakage relay and one or two EFCT-series
current sensors connected as shown in Fig. 4. The system
can use CT1 and CT2 individually or combined. See
Section 4.
Pass the phase conductors through the CT window(s)
and position them in the centre of the opening (for 4-wire
and single-phase systems, also pass the neutral conductor
through the CT window). Do not pass earth conductors
through the CT window. In applications that require
shields or drain wires to pass through the CT window,
return them through the CT window before connecting
them to earth. For applications utilizing the primary-turns
feature, pass the phase conductors through the opening
additional times as required (maximum of 5).
Using shielded twisted-pair cable, connect CT1 to
terminals 7 and 8 and connect the shield to terminal 6.
Current-sensor connections are not polarity sensitive. See
Figs. 9, 10 and 11 for current-sensor dimensional
drawings.
Using shielded twisted-pair cable, connect CT2 to
terminals 10 and 11 and connect the shield to terminal 9.
Current-sensor connections are not polarity sensitive. See
Figs. 9, 10 and 11 for current-sensor dimensional
drawings.
Each EFCT-series sensor includes 6 m (19.2’) of cable.
NOTE:CT1 emits an audible tone when operating
properly.
2.1.3 ANALOG OUTPUT
The 4-20-mA analog output is loop powered. Connect
as shown in Fig. 4. The analog output is isolated to 120
Vac from all other EL731 terminals.
2.1.4 PTC OR RTD INPUT
The temperature-sensor input can be configured for
either RTD or PTC operation. Connect as shown in
Fig. 4.
Select the sensor type in the Setup | Hardware | Temp
Sensor menu.
2.1.5 COMMUNICATIONS (OPTIONAL)
The EL731 supports optional communications upgrade
adapters which install through the side of the enclosure as
shown in Fig. 7.
To field-install an AC700-CUA-series
Communications Upgrade Adapter, follow this procedure:
Remove supply voltage from the EL731.
Remove the adapter access cover on the side of the
EL731.
Insert the adapter, and retain with the supplied
screws.
Apply supply voltage to the EL731.
With an EtherNet/IP or Modbus TCP communications
adapter installed, a standard RJ45 network cable can be
used to connect the EL731 to an EtherNet/IP or Modbus
TCP network. Configure the interface using the IP
Configuration Tool (IP Config) available at
www.littelfuse.com/relayscontrols. The software
requires a Microsoft Windows™ operating system. The
Ethernet interface supports 10/100-Mbit, full- or half-
duplex operation.
Connect the EL731 to the network using a standard
Ethernet patch cable. Use of a crossover cable to connect
the EL731 directly to the computer running IP Config is
not recommended. A typical router will assign an IP
address to all connected computers that are using DHCP.
The EL731 is not configured to accept an IP address using
DHCP.
If the EL731 is being set up for first time, it is
recommended to only have one EL731 connected to the
network to prevent communication errors.
With a DeviceNet communications adapter installed, a
standard open-style device cable can be used to connect
the EL731 to a DeviceNet network. Configure the address
and baud rate through the EL731 front-panel interface or
with Rockwell Automation’s RSNetWorx software. The
DeviceNet interface supports baud rates of 125, 250, and
500 kbps.
2.1.6 REMOTE RESET
If required, connect a normally open momentary switch
to the remote-reset input (terminals 12 & 13) as shown in
Fig. 4.
2.1.7 RELAY OUTPUTS
The EL731 has three programmable Form-C
(changeover) relay outputs. Functional assignments are
Trip, Alarm, Watchdog or Current Detected. See Section
3.2.3.3.
2.2 CALIBRATION
If the low-frequency CT1 input is used, the EL731 must
be calibrated in order to ensure an accurate current
measurement.
Page 3
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
To calibrate, connect an EFCT-series current sensor to
the EL731 and ensure that no CT-primary current is
present. Apply EL731 supply voltage and navigate to
menu item Setup | Protection | CT1 Earth Fault |
Calibrate. Press Enter to begin the calibration process.
The CT LED will flash, during the calibration process,
which takes about 30 seconds.
If the CT is replaced, this procedure must be repeated
to maintain current-measurement accuracy.
FIGURE 1. EL731 Outline and Mounting Details.
48.0
(1.89)
96.0
(3.78)
91.5
(3.60)
FRONT
TOP
PANELTHICKNESS
1.6 (0.06)TO 4.8 (0.19)
SIDE
43.9
(1.73)
119.0 MAX
(4.68)
10.0
(0.39)
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
REAR
PANEL CUTOUT DETAIL
92.0
(3.62)
44.0
(1.73)
R=4.8 (0.19)
MAXIMUM
100.0 MINIMUM
(3.94)
50.0 MINIMUM
(1.97)
COMMUNICATIONS
ADAPTER
ACCESS COVER
CLAMP RETAINER
GROOVES
PANEL-MOUNT CLAMP
Associated Equipment:
EFCT-1, EFCT-2, EFCT-26, EFCT-5RF EFCT-6RF, EFCT-7RF,
EFCT-8RF,EFCT-9RF, EFCT-10RF Current Transformers
Operating Time: 35 ms minimum
500 ms maximum
Operating Current: 50 A maximum
2.5 s withstand
AS/NZS 2081: 2011
Section 6 Compliant
Revision:
Supply:
Contact Ratings for Relay 1:
Relay 2 & 3: 8 A 250 Vac 500 VA/8 A 30 Vdc 48 W
5 A 250 Vac 300 VA/5 A 30 Vdc 28 W
EL731-
EL731-
01
01-10
AC/DC SENSITIVE
EARTH-LEAKAGE RELAY
Serial No:
1-800-TEC-FUSE (1-800-832-3873)
Made in Saskatoon, Canada
Network Communications: DeviceNet™
~
13 VA 120-240 Vac (+10, -45%) 50/60 Hz
7 W 100-250 Vdc (+10, -25%)
AS/NZS 2081:2011 Compliant
Ground Fault Sensing
and Relaying Equipment
4FX9 E340889
®
LR 53428
USC
R
Page 4
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 2. AC700-SMK Outline and Mounting Details.
FIGURE 3. Panel and Surface Mounting Connections.
MOUNTING DETAIL BOTTOM VIEW
FRONT VIEWSIDE VIEW
60.0
(2.36)
112.0
(4.41)
100.0
(3.94)
M4 OR 8-32TAP
12.0
(0.47)
81.2
(3.20)
21.2
(0.83)
112.0
(4.41)
81.2
(3.20)
125.4
(4.94)
121.9
(4.80) 100.0
(3.94)
60.0
(2.36)
81.2
(3.20)
M4 OR 8-32TAP
4 LOCATIONS
CABLE-TIE EYELET
4 LOCATIONS
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. SIDE VIEW SHOWN WITH 35 MM x 7.5 MMTOP-HAT RAIL.
14
15
1617
18
19202122
23
24
2526 14 15 16 17 18 19 2 0 21 22 23 24 25 26
1234 5678910
11 12 13
L1
L2/N
NCK1K2K3
POWER
RELAY 1RELAY 2RELAY 3 POWER RELAY 1 RELAY 2 RELAY 3
ANALOG OUT RTD / PTC CT1 CT2 REMOTE
RESET
AA AB TA TB TC SH1 S12 S11 SH2 S22 S21 GND RST
L1 L2/N NC K1 K2 K3
PANEL MOUNTED SURFACE MOUNTED
12
3
4
56
7
8
910111213
AAAB
TA
TB
TC
SH1
S12S11SH2S22S21
GNDRST
ANALOG OUT
RTD / PTCCT1
CT2
REMOTE
RESET
12345678910 11 12 13
14 15 16 17 18 19 20 21 22 23 24 25 26
Page 5
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 4. Connection Diagram.
EL731
REMOTE
RESET
4-20 mA
14
K1
K2
K3
L1
19
22
25
S11
S12
SH1
RST
GND
13
12
L2/N 15
16
18
21
23
24
26
17
5
4
3
NC
TC
TB
TA
RTD/PTC
2
AB
1
AA
ANALOG
OUT
+tº
TA
TB
TA
PTC RTD
tº
SUPPLY
+
-
PGA-0520
NOTES:
1. CT CONNECTIONS ARE NOT POLARITY
SENSITIVE.
2. CT1 AND CT2 ARE INTERNALLY REFERENCED TO
TERMINAL 16. DO NOT CONNECT ADDITIONAL
EARTHS TO CT1 OR CT2.
3. FREQUENCY RESPONSE OF CT1 IS DC TO 90 HZ
AND CT2 IS 20 TO 6,000 HZ. USE ONE OR BOTH
INPUTS TO PROVIDE DESIRED FREQUENCY
RESPONSE. SEE SECTION 4.
4. RELAY CONTACTS SHOWN WITH THE EL731
DE-ENERGIZED.
5. ALTERNATE CT LOCATIONS.
6. IF AN EARTH-FAULT OCCURS IN THE RECTIFIER
PORTION OF AN ASD, THIS CONTROL SCENARIO
MIGHT BE INSUFFICIENT. TRIP THE CIRCUIT
BREAKER UPSTREAM FROM THE ASD.
L1
Ø A
Ø B
Ø C
EFCT-X
L2/N
R
Y
G
TRIP
ALARM
CT
OPTIONAL NETWORK
COMMUNICATIONS
S21S22SH2
EFCT-X
TC TC
20 ASD
RUN
FAULT
TB
ADJUSTABLE-
SPEED
DRIVE
(ASD)
NOTE 5
NEUTRAL-EARTHING
RESISTOR
NOTE 5
678 91011
DISPLAY:
2 x 16
ALPHANUMERIC
OLED
INDICATION
CT1 CT2
NOTE 3
EARTHED
DC SYSTEM
+
-
EL731
87
N
20
EFCT-X
DC CIRCUIT
MONITORING
NOTE 6
Page 6
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 5. AC700-CVR-00 Weatherproof Cover Outline.
30.9
(1.22)
67.6
(2.66)
131.7
(5.19)
TOP VIEW
FRONT VIEW
NOTES:
1. DIMENSIONS SHOWN IN MILLIMETRES (INCHES).
2. TIGHTENINGTORQUE 0.02 N·M (0.18 LBF·IN).
3. POLYCARBONATE FRONT COVER CAN BE CLEANED USING WATER, METHANOL, OR ETHANOL.
SIDE VIEW
PANEL CUTOUT DETAIL
92.0
(3.62)
44.0
(1.73)
R=4.8 (0.19)
MAXIMUM
160.0 MINIMUM
(6.30)
73.0 MINIMUM
(2.87)
Page 7
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 6. AC700-CVR-00 Weatherproof Cover Installation.
FRONT-PANEL
DETAILS NOT SHOWN.
INSERTTHE EL731THROUGHTHE OPENING OFTHE
WEATHERPROOF WINDOW.
INSERT ASSEMBLY INTO PANEL AND SECURE WITH
THE PANEL-MOUNT CLAMP. REFERTO SECTION 2
FOR DETAILS.
Page 8
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 7. EL731 with installed EtherNet/IP™ Communications Upgrade Adapter (AC700-CUA-03).
FIGURE 8. EL731 with Firmware Upgrade Module (AC700-CUA-00).
Page 9
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
3. OPERATION AND SETUP
3.1 DISPLAY AND INDICATION
The EL731 front panel has three LED’s, a
2-line x 16-character alphanumeric OLED display and
four push buttons to navigate through programming,
status, and system-information menus. The display will
revert to screen-saver mode after 10 minutes. Press any
button to exit the screen saver.
The RESET button is used to clear an earth-leakage or
overtemperature trip. The fault condition must no longer
be present to allow a reset. Continually pressing the reset
button will not prevent a trip.
The RESET button has a second function that is useful
when navigating the menus. If the button is pressed for a
short time, upon release the active menu item will exit,
either returning to the previous menu item or the status
screen.
The up and down arrow buttons (▲▼) are used to
navigate the menu system or modify settings.
The ENTER button is used to select menu items and to
choose settings.
All EL731 settings can be accessed using the EL731
menu system or the optional network communications
interface. In the following sections, menu items and setup
parameters are listed in italics and are shown in the format
displayed on the OLED display.
Menu selection is in the following format:
Menu 1 | Sub Menu 1 | Sub Menu 2 | Sub Menu 3 |…
When browsing a selection list, an asterisk (*) indicates
the active item. If the intent is to exit the list and not to
change the setting, press ENTER on the selection that has
the asterisk (*).
If the item is a string (or numerical) input and no change
is desired, press ENTER until the display returns to the
menu system. To exit a main-menu list, scroll and select
Exit, or press the RESET button.
A menu map is provided in Appendix A at the end of
this manual.
3.1.1 FRONT-PANEL LED INDICATION
3.1.1.1 TRIP
The red LED labelled TRIP indicates a trip condition
when flashing. Refer to Table 1 for applicable flash codes.
TABLE 1. TRIP LED FLASH CODES
FAULT CODES
CT1 Earth Fault 1 Short, 1 Long
CT2 Earth Fault 2 Short, 1 Long
CT1 Detection Failure 3 Short, 1 Long
CT2 Detection Failure 4 Short, 1 Long
NVRAM Error 5 Short, 1 Long
CT1 Calibration Failure 6 Short, 1 Long
RTD/PTC Trip 7 Short, 1 Long
User Test 8 Short, 1 Long
Watchdog Fast Flash
Trip cause is also available on the OLED display
through the Messages | State menu item.
3.1.1.2 CT STATUS
The green LED labelled CT will flash during CT1
calibration. It will be solid green when CT connections are
correct, and off when a CT is connected incorrectly.
3.1.1.3 ALARM
The yellow LED labelled ALARM will be on when
measured current is above the alarm setting.
3.1.2 COMMUNICATIONS-MODULE LED INDICATION AND
STATUS
See the associated interface manual, available at
www.littelfuse.com/relayscontrols.
3.2 MAIN MENUS
The “top” menu item (select Exit in the main menu)
displays earth-leakage current(s) as a numeric percentage
of full scale (5 A, depending upon the primary turns
setting) and as a bar graph.
3.2.1 METERING
Menu: Metering
With Metering selected in the main menu, press the
ENTER button to display a list of metering options. Use
the Up and Down arrow buttons to scroll through the
options list. Press the ENTER button to display the
selected information.
Information available: CT1 primary current (mA), CT2
primary current (mA), combined CT1 and CT2 current
(mA), internal EL731 temperature (°C and °F), PTC
status, and RTD temperature (°C and °F).
The CT2 metering range is trip-level dependent. When
the CT2 trip level is set to less than 250 mA, the CT2
meter range is 0 to 2.5 A. When the CT2 trip level is set
to greater than or equal to 250 mA, the meter range is 0 to
5 A.
3.2.2 MESSAGES
Menu: Messages
Selecting this menu item allows the trip state, alarm
state, trip counter, alarm counter, system uptime, and
running time to be viewed.
System uptime is the amount of time since the last
restart or supply voltage cycle. Running time is the total
amount of time the system has been in operation, and is
retained through power cycles.
Page 10
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
3.2.3 SETUP
See Appendix B for a Setup Summary and Setting
Record.
3.2.3.1 EARTH-FAULT PROTECTION
Menu: Setup | Protection | CTx Earth Fault
The Earth Fault Enable/Disable menu enables or disables
current monitoring through the selected CT input. When
enabled, the system checks to ensure the CT is connected
properly. A trip will occur if an EFCT is not connected. See
Section 3.1.1.1.
The Primary Turns menu sets the number of passes
through the CT primary by the phase conductors. The range
is 1 to 5 turns, where 1 is the default. If set to another value,
ensure the phase conductors pass through the CT window
the correct number of times. This setting affects the
trip/alarm range.
The Trip Time menu sets the trip delay. The range is 0 to
2 seconds in millisecond increments where 0 indicates that
as soon as current is detected above the Trip Level, a trip
occurs.
The TripLevelmenu sets the trip level. The default setting
range is 30 mA to 5 A, but this is affected by the Primary
Turns setting. The Alarm Level setting range is the same as
the Trip Level range. Trips are latched, requiring a local or
remote reset input, and alarms auto-reset.
The Calibrate menu applies to CT1 (0 to 90 Hz). When
CT1 is used, the EL731 must be calibrated after installation.
See Section 2.2.
The Input Filter menu applies to CT2 (20 to 6,000 Hz)
and allows selection of different input filters. The available
filters and their descriptions are shown in Table 2.
TABLE 2. CT2 INPUT FILTERS
FILTER FREQUENCY RESPONSE
Full Range (Default) 20 to 6,000 Hz
90 Hz Low Pass Filter 20 to 90 Hz
190 Hz High Pass Filter 190 to 6,000 Hz
3 kHz Low Pass Filter 20 to 3,000 Hz
For full-spectrum protection, use CT1 and CT2 and select
the 190 Hz High Pass Filter to avoid frequency overlap
between the inputs.
3.2.3.2 TEMPERATURE PROTECTION
Menu: Setup | Protection | PTC Local Temp
Menu: Setup | Protection | RTD Local Temp
Menu: Setup | Hardware | Temp Sensor
The temperature-sensor input, at terminals 3, 4, and 5,
can be configured as a PTC thermistor or a 100-ohm-
platinum RTD (or disabled) in the Setup | Hardware |
Temp Sensor menu. Overtemperature alarm and trip
actions can be selected in the Setup | Protection | PTC
Temperature menu, or in the Setup | Protection | RTD
Temperature menu.
3.2.3.3 OUTPUT-RELAY ASSIGNMENTS
Menu: Setup | Relay Outputs | Relay x
Each of the three output relays can be assigned to one
of the functions listed in Table 3. More than one output
can be assigned the same function.
TABLE 3. OUTPUT-RELAY FUNCTIONS
FUNCTION ASSIGNMENT OR
ACTION
DEFAULT
ASSIGNMENT
Trip Relay de-energized in fail-
safe mode when trip occurs.
Fail-safe or non-fail-safe(1)
mode selection is available.
Relay 1, Fail-safe
Mode
Alarm Relay de-energized in fail-
safe mode when alarm is
present. Fail-safe or non-
fail-safe(1) mode selection is
available.
Relay 2, Fail-safe
Mode
Watchdog Relay is energized in fail-
safe mode when the supply
voltage is applied and the
EL731 is operating
properly. Fail-safe or non-
fail-safe mode selection is
available.
Relay 3, Fail-safe
Mode
Current
Detected
Relay is energized in fail-
safe mode when current is
detected on CT1 or CT2.
Fail-safe or non-fail-safe
mode selection is available.
Fail-safe Mode
(1) Fail-safe only for AS/NZS 2081:2011 option.
The Fail-safe Mode setting for each output relay allows
the individual output relay to be configured as fail-safe
(normally energized) or non-fail-safe (normally de-
energized).
The Test function performs a test of the specified relay.
During the test, the relay is energized for one second and
de-energized for one second. This sequence is performed
once per test.
3.2.3.4 ANALOG OUTPUT
Menu: Setup | Analog Output
A 4–20-mA programmable current output is provided.
When Analog % Level is enabled the output is
configured such that 20 mA corresponds to full scale of
the selected CT Trip Level. When disabled it corresponds
to the full scale of the selected CT.
CT Select selects which CT measurement will be
represented by the analog output. The selections are CT1,
CT2, and Full Current. When set to Full Current, the
current measured by each CT makes up 50% of the total
Analog Output level.
Output Filter passes the output through an averaging
filter, providing a smoother analog output signal in noisier
applications.
Page 11
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
3.2.3.5 MISCELLANEOUS CONFIGURATION
Menu: Setup | System Config
Used to access additional system configuration elements
described in the following sections.
3.2.3.5.1 PASSWORD
Menu: Setup | System Config | Change Password
Menu: Setup | System Config | Password Enable
Used to enable and change the EL731 password (four-
character numeric field). When enabled, the password
must be entered to change a set point. The default
password is 1111.
3.2.3.5.2 RESET PASSWORD
Menu: Setup | System Config | Chg Reset Pwd
Menu: Setup | System Config | Reset Pwd En
Used to enable and change the EL731 reset password
(four-character numeric field). When enabled, the reset
password must be entered to reset the EL731. The default
reset password is 1111.
3.2.3.5.3 MENU TIMEOUT
Menu: Setup | System Config | Menu Timeout
Used to set the time before the system times out due to
lack of activity and the menu system returns to the main
menu display (See Section 3.2). In password mode the
password entered will be cleared. The timeout is measured
from the last button press.
The display will revert to screen-saver mode 10 minutes
after the menu timeout occurs.
3.2.3.5.4 DISPLAY FILTER
Menu: Setup | System Config | Display Filter
Used to enable an averaging filter for current displayed
on the display through the metering menu. See Section
3.2.1.
3.2.3.5.5 MAINTENANCE
Menu: Setup | System Config | Maintenance
Used to clear trip and alarm counters, load defaults,
restart the system, and display the model option, firmware
version, build date, and serial number.
3.2.4 PASSWORD
Menu: Password
With password security active, all set points are locked.
To enable programming, the password must be entered
through the Password menu.
While navigating through the menus when a valid
password has been entered, an asterisk (*) is shown at the
beginning of the first line of the display.
3.3 TRIP RESET
The RESET button will clear a trip when pressed for
2.5 s if the fault is no longer present. Keeping RESET
pressed will not prevent an alarm or trip. If the reset
password is enabled, reset will not function until the
password has been entered through the Password menu.
Momentarily connect Remote Reset terminals 12 and
13 for 2.5 s to reset a trip when the fault is no longer
present.
If an optional network adapter is installed, an EL731
trip can be reset with a network command when the fault
is no longer present, even if a reset password is enabled.
Page 12
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 9. EFCT-1 Outline and Mounting Details.
LR 53428
USC
R
R
121.0
(4.76)
20.5
(0.81)
M5 SCREWS
30.0
(1.18)
56.0
(2.21)
46.0
(1.81)
121.0
(4.76)
80.0
(3.15)
NOTE 2
MOUNTING DETAIL
TOP
25.0
(0.98)
82.0
(3.23)
69.8
(2.75)
EFCT - 1FC
FLUX
CONDITIONER
(OPTIONAL)
138.0 MAX
(5.43)
5.5
(0.22)
110.0
(4.33)
5.5
(0.22)
22.0
(0.87)
5.0 (0.20) Ø
RECESSED FOR
8-mm HEX NUT
1.0 (0.04) DEEP
FRONT
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M4 OR 8-32.
3. PRESS MOUNTING FEET IN PLACE USING
INSTALLATIONTOOL PROVIDED.
4. RoHS COMPLIANT.
5. EN 60044-1 COMPLIANT.
30.0
(1.18)
SIDE
56.0
(2.21)
126.0
(4.96)
EFCT-1 EARTH FAULT CT
600 V CLASS, INSULATION CLASS A
Page 13
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 10. EFCT-2 Outline and Mounting Details.
P
P
SS
2
2
11
215.0
(8.46)
64.0
(2.52)
31.0
(1.22)
M5 SCREWS
TOP MOUNTING DETAIL
52.3
(2.06)
215.0
(8.46)
162.0
(6.38)
M5 OR 10-32TAP
26.5
(1.04)
25.0
(0.98)
236 MAX
(9.29)
139.7
(5.50)
FLUX CONDITIONER
(INCLUDED)
BONDING
SCREW
5.0 (0.20) DIA
8.5
(0.33)
8.5
(0.33)
SIDE
31.0
(1.22)
198.0
(7.80)
60.0
(2.36)
FRONT
215.0
(8.46)
LR 53428
USC
R
R
EFCT-2 EARTH FAULT CT
600 V CLASS, INSULATION CLASS A
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M5 OR 10-32.
3. RoHS COMPLIANT.
4. EN 60044-1 COMPLIANT.
Page 14
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 11. EFCT-26 Outline and Mounting Details.
P
P
SS
2
2
1
1
26.5
(1.04)
68.0
(2.68)
17.0
(0.67)
M5 SCREWS
TOP
68.0
(2.68)
34.0
(1.34)
52.5
(2.07)
42.6
(1.68)
M4 OR 8-32TAP
MOUNTING DETAIL
25.0
(0.98)
110.0 MAX
(0.43)
72.0
(2.83)
34.0
(1.34)
26.0
(1.02)
58.0
(2.28)
5.0
(0.20)
5.0
(0.20)
7. 0
(0.87)
4.0 (0.16) Ø
RECESSED FOR
7-mm HEX NUT
3.0 (0.12) DEEP
FRONT
26.5
(1.04)
52.5
(2.07)
SIDE
MOUNTING FOOT
INSTALLATION
TOOL
DETAIL ‘A’
LR 53428
USC
R
R
EFCT-26 EARTH FAULT CT
600 V CLASS, INSULATION CLASS A
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M4 OR 8-32.
3. PRESS MOUNTING FEET IN PLACE USING
INSTALLATIONTOOL PROVIDED.
(DETAIL ‘A’)
4. RoHS COMPLIANT.
5. EN 60044-1 COMPLIANT.
6. NOT ALL CERTIFICATIONS SHOWN.
Page 15
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
FIGURE 12. PGA-0520 Analog Percent Current Meter.
4. THEORY OF OPERATION
CT1 and CT2 have independent Trip and Alarm
current-level and time-delay set points and independent
metering. This enables different protection levels and
separate metering for the high- and low-frequency ranges.
Full-current metering, summing CT1 and CT2
metering, is provided as an OLED metering selection, an
analog output selection, and in optional network
communications. To improve full-current-metering
accuracy by avoiding band overlap, select the CT2 high-
pass filter.
For CT-location and adjustable-speed-drive-application
information, see Technical Note GF-11 “Ground-Fault
Monitoring in Adjustable-Speed Drive Applications”
located at www.littelfuse.com/relayscontrols.
4.1 CT1 THEORY OF OPERATION
The EL731 applies a known signal to the secondary
winding of the EFCT-series sensor connected to input
CT1. Current flowing in the EFCT primary affects this
signal, and its magnitude can be accurately measured
across a wide frequency range. The EL731 can measure
current as low as 30 mA (6 mA with primary turns setting)
in a frequency range of 0 to 90 Hz. If an open or short
EFCT connection is detected, a trip occurs.
Compatible CT’s include the EFCT-1, EFCT-2, and
EFCT-26. See Section 7.
4.2 CT2 THEORY OF OPERATION
CT2 is a core-balance zero-sequence current-
transformer application, with digital filtering to enable a
wide spectrum of detection.
There are four digital-filter ranges: Full Range, 90 Hz
Low Pass, 3 kHz Low Pass, and 190 Hz High Pass.
If an open or short EFCT connection is detected, a trip
occurs. See Table 1.
Compatible CT’s include the EFCT-1, EFCT-2, EFCT-
26, and the EFCT-xRF series. See Section 7.
4.2.1 CT2 FULL RANGE FILTER
The Full Range filter selection configures the EL731 to
respond to the entire frequency spectrum that CT2 is
capable of monitoring–20 to 6,000 Hz.
4.2.2 CT2 90 Hz LOW PASS FILTER
The 90 Hz Low Pass filter selection configures the
EL731 to respond to only the low end of its frequency
range–20 to 90 Hz.
%
100
0
20
40
80
60
®
67.5
(2.657)
R1.25(0.049)
MAXIMUM
67.5
(2.657)
66.0
(2.598)
48.0
(1.890)
TOP MOUNTING CUTOUT
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
71.0
(2.795)
65.0
(2.559)
ANALOG % CURRENT METER
PGA-0520
REARSIDE
FRONT
Page 16
EL731 AC/DC Sensitive Earth-Leakage Relay Rev. 6-F-032816
4.2.3 CT2 3 kHz LOW PASS FILTER
The 3 kHz Low Pass filter selection configures the
EL731 to respond to the 20 to 3,000 Hz frequency range.
4.2.4 CT2 190 Hz HIGH PASS FILTER
The 190 Hz High Pass filter selection configures the
EL731 to respond to only the high end of its frequency
range, 190 to 6,000 Hz.
5. PERSONAL COMPUTER INTERFACE
5.1 FLASH MEMORY UPGRADE
The EL731 control program is stored in flash memory.
This allows field upgrades to be made through the upgrade
module (optional). The following are required:
Windows PC with a USB interface and the SE-Flash
program installed; SE-Flash is available at
www.littelfuse.com/relayscontrols
File containing the EL731 control program (.s19 file)
USB cable or a TIA232 (through a CA-945 converter)
with Ethernet cable
AC700-CUA-00 Firmware Upgrade Module
6. TECHNICAL SPECIFICATIONS
6.1 EL731
Supply:
Option 0 .................................13 VA, 120 to 240 Vac
(+10, - 45%), 50/60 Hz;
7 W, 100 to 250 Vdc
(+10, - 25%)
Option 1 .................................7 W, 32 to 60 Vdc
(+20,-25%),
Nominal 48 Vdc;
9 VA, 24 to 44 Vac
(±10%), 50/60 Hz
Option 2 .................................7 W, 16 to 30 Vdc
(+20,-25%),
Nominal 24 Vdc
DC and Low Frequency (Current Transformer 1):
Frequency Response........... DC to 90 Hz
Measurement Method ......... True RMS
Detection Method ............... CT Driven Oscillator
Trip-Level Setting............... 30 to 5,000 mA
Trip-Level Primary Turns
Lowest Alternate Range... 6 to 1,000 mA
Alarm-Level Setting ........... 30 to 5,000 mA
Alarm-Level Primary Turns
Lowest Alternate Range... 6 to 1,000 mA
Trip-Time Settings.............. 0 to 2 s
AS/NZS 2081 Option....... 0 to 500 ms
Trip Accuracies:
Trip Level ........................ Maximum of 10%
Time Delay(1) ...................- 5% setting + 35 ms
CT ....................................... EFCT series
Cable Resistance................. 1 ΩMaximum
Thermal Withstand:
Continuous .......................25 A Earth-Fault
Current
1 second ...........................400 A Earth-Fault
Current
Detection.............................CT Open & Short
AC/Carrier (Current Transformer 2):
Frequency Response:
Full Range Filter ..............20 to 6,000 Hz
90 Hz Low Pass Filter .....20 to 90 Hz
190 Hz High Pass Filter ...190 to 6,000 Hz
3 kHz Low Pass Filter ......20 to 3,000 Hz
Measurement Method .........True RMS
Detection.............................CT Open & Short
Meter Range:
Trip Level < 250 mA........0 to 2.5 A
Trip Level ≥250 mA........0 to 5 A
Trip Level Setting ...............30 to 5,000 mA
Trip-Level Primary Turns
Lowest Alternate Range......6 to 1,000 mA
Alarm Level Setting............30 to 5,000 mA
Alarm-Level Primary Turns
Lowest Alternate Range......6 to 1,000 mA
Trip-Time Settings..............0 to 2 s
AS/NZS 2081 Option.......0 to 500 ms
Trip Accuracies:
Trip Level:
30 to 5,000 mA..............Maximum of 10% (at
50/60 Hz)
Trip Time(1) ......................- 5% setting + 25 ms
(at 50/60 Hz)
CT .......................................EFCT and
EFCT-RF(2) series
Cable Resistance .................1 ΩMaximum
Thermal Withstand:
Continuous .......................25 A Earth-Fault
Current
1 second ...........................400 A Earth-Fault
Current
Detection.............................CT Open, Short, and
Saturation
Output Relays:
Relay 1:
Contact configuration.......N.O. and N.C., Form-C,
changeover
Operating Mode ...............Fail-Safe/Non-Fail-Safe
CSA/UL Rating................8 A Resistive, 250 Vac,
8 A Resistive, 30 Vdc
AS/NZS 2081 Rating .......8 A Resistive, 250 Vac,
500 VA
8 A Resistive, 30 Vdc,
48 W
Supplemental Contact Ratings
Make/Carry 0.2 s...........30 A
Rating Code...................B300
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