

The SE-701 series is a microprocessor-based, ground-fault relay for resistance-grounded and solidly grounded ac systems. In addition to common systems, it is uniquely suited for use on systems with significant harmonic content. The SE-701 can provide main-plant protection, feeder-level protection, or individual-load protection. Proper current transformer selection provides the desired pickup range. The output contacts can be connected for use in protective tripping circuits or in alarm indication circuits. Its output relay can operate in the fail-safe or non-fail-safe mode for undervoltage or shunt-trip applications. The analog output can be used with a PLC or a meter.
- Adjustable pickup (1–99 %)
- Adjustable time delay (50–2.5 ms)
- Output contacts
- Analog outputs (0–5 V)
- CT-loop monitoring
- Selectable DFT or peak detection filtering
- Harmonic filtering
- Non-volatile trip memory
- Microprocessor-based
- Universal power supply
- Trip setting based on input CT primary - allows use with any CT. Minimum 50 mA with EFCT series
- Adjustable trip delay allows quick protection and system coordination
- Form A and Form B ground-fault output contacts for operation of separate annunciation and trip circuits
- Allows for connecting an optional meter (PGA-0500) or a control system
- Alarms when CT is not connected
- Compatible with variable speed drives
- Eliminates nuisance tripping
- Retains trip state while de-energized to simplify troubleshooting
- No calibration required - saves on maintenance cost
- Allows operation in application where one side of PT is faulted, provides flexibility for numerous applications
SE-701 Parts
Filters
Part Number | Actions | Supply Voltage AC | Supply Voltage DC | Relay Contacts Config | Analog Output Voltage (V) | IEEE Device Numbers | Relay Contacts Operation | Weight (kg) | Auto Manual Reset | Conformally Coated | CT Loop Monitoring | Frequency (Hz) | GF Trip Level Range (%) | GF Trip Time (s) | Harmonic Filtering | Reset Type | System Type | Test Button |
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Part Number | Actions | Supply Voltage AC | Supply Voltage DC | Relay Contacts Config | Analog Output Voltage (V) | IEEE Device Numbers | Relay Contacts Operation | Weight (kg) | Auto Manual Reset | Conformally Coated | CT Loop Monitoring | Frequency (Hz) | GF Trip Level Range (%) | GF Trip Time (s) | Harmonic Filtering | Reset Type | System Type | Test Button | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
24 | 1 Form A (N.O.); 1 Form B (N.C.) | 0 - 5 V | 50G - 50N - 51G - 51N | Fail-safe / Non Fail-safe | 0 Kg (kilogram) | Latching; Autoreset | Optional | Standard | 50; 60; ASD | 1 - 99% of CT-Primary Rating | 0.5 - 2.5 | Standard (DFT) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC; Resistance Grounded AC | Front-panel switch | ||||
0 Kg (kilogram) | |||||||||||||||||||
12 - 24 | 1 Form A (N.O.); 1 Form B (N.C.) | 0 - 5 V | 50G - 50N - 51G - 51N | Fail-safe / Non Fail-safe | 0 Kg (kilogram) | Latching; Autoreset | Optional | Standard | 50; 60; ASD | 1 - 99% of CT-Primary Rating | 0.5 - 2.5 | Standard (DFT) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC; Resistance Grounded AC | Front-panel switch | ||||
0 Kg (kilogram) | |||||||||||||||||||
48 | 1 Form A (N.O.); 1 Form B (N.C.) | 0 - 5 V | 50G - 50N - 51G - 51N | Fail-safe / Non Fail-safe | 0 Kg (kilogram) | Latching; Autoreset | Optional | Standard | 50; 60; ASD | 1 - 99% of CT-Primary Rating | 0.5 - 2.5 | Standard (DFT) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC; Resistance Grounded AC | Front-panel switch | ||||
0 Kg (kilogram) | |||||||||||||||||||
120 / 240 | 120 / 240 | 1 Form A (N.O.); 1 Form B (N.C.) | 0 - 5 V | 50G - 50N - 51G - 51N | Fail-safe / Non Fail-safe | 0 Kg (kilogram) | Latching; Autoreset | Optional | Standard | 50; 60; ASD | 1 - 99% of CT-Primary Rating | 0.5 - 2.5 | Standard (DFT) | Front-panel switch/Remote N.O. Contact | Solidly Grounded AC; Resistance Grounded AC | Front-panel switch | |||
0 Kg (kilogram) |
SE-701 Applications
- Resistance-grounded and solidly grounded ac systems
Series: SE-701 Resources

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