

The EL731 series relay operates on ac resistance-grounded systems and dc grounded systems. This unit is a microprocessor-based ac, dc, sensitive, earth-leakage relay that offers complete coverage for all frequencies from 0–6,000 Hz. Two CTs are required for the entire frequency range, or one CT can be used for only low- or high-frequency detection. An RTD/PTC temperature sensor input allows over-temperature protection. The EL731 offers metering capabilities, password-protected alarm and trip settings, and optional network communications. The EL731 is used to add low-level ground-fault protection to variable-speed drives and to dc currents.
Computer-to-Relay Connection
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 does not support the use of 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.
- Adjustable pickup (30–5,000 mA)
- Frequency range (0–90 Hz, 20–6,000 Hz)
- 32-character OLED display
- Local LED indication
- CT-loop monitoring
- Analog output (4–20 mA)
- Adjustable time delay
- Alarm and trip settings
- Temperature sensor input
- Output contacts
- Adjustable trip setting provides a wide range of low-level protection and system coordination
- Operates in either ac or dc mode or both. Use single or combined ranges. Separate metering
- Earth-leakage metering, set up, and programming
- Visual trip, alarm, CT connection indication
- Alarms when CT is not connected
- Connect to DCS. Allows connection to an optional meter (PGA-0520) or control system
- Adjustable trip delay for quick protection and system coordination
- Detects a deteriorating condition before damage occurs
- Drive or motor temperature protection
- Three programmable: operate two alarm and one trip circuit
EL731 Parts
Filters
Part Number | Actions | Supply Voltage AC | Supply Voltage DC | Relay Contacts Config | Communications | IEEE Device Numbers | Relay Contacts Operation | Dimensions | Weight (kg) | Auto Manual Reset | Conformally Coated | Frequency (Hz) | GF Trip Level A | GF Trip Time (s) | Harmonic Filtering | Mount Method | Reset Type | System Type | Temp Sensor Config |
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Part Number | Actions | Supply Voltage AC | Supply Voltage DC | Relay Contacts Config | Communications | IEEE Device Numbers | Relay Contacts Operation | Dimensions | Weight (kg) | Auto Manual Reset | Conformally Coated | Frequency (Hz) | GF Trip Level A | GF Trip Time (s) | Harmonic Filtering | Mount Method | Reset Type | System Type | Temp Sensor Config | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | None | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance Grounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | None | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance Grounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | DeviceNet | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance Grounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | DeviceNet | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | Profibus | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | DeviceNet | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | EtherNet - IP | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | EtherNet - IP | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | Modbus TCP | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
120 / 240 | 120 / 240 | 3 Form C (N.O./N.C.) | Modbus TCP | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
24 | 48 | 3 Form C (N.O./N.C.) | None | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD | |||
24 | 48 | 3 Form C (N.O./N.C.) | 38 - 49 - 50G - 50N - 51G - 51N - 79G | Fail-safe / Non Fail-safe | 1.9 H x 3.8 W x 5 D in. | 0 Kg (kilogram) | Latching trip - Non-latching alarm | Standard | 0 - 6000 | 0.03 - 5.00 | 0.05 - 2.00 | Standard | DIN (optional) - Panel - Surface (optional) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC - Solidly Grounded DC - Resistance rounded AC | Single PTC/RTD |
EL731 Applications
- Resistance grounded ac systems and dc grounded systems
Series: EL731 Resources

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