Sigma D

Directional short-circuit and earth fault indicator

The Sigma D is a combined directional short-circuit and directional earth fault indicator for medium voltage distribution networks.

The devices are current sensor powered. The voltage information will be taken from an integrated voltage detecting system (Wega series), from an HR interface or capacitive post insulators.

Equipment set includes:

1 display unit
3 phase current sensors
Voltage coupling

CT powered directional short-circuit and directional earth fault indicator for all distribution networks / neutral point treatments
The Sigma D can be used in isolated networks with open rings
Fully automatic voltage calibration
Easy and flexible parameter setting via DIP switch or USB port
Event memory for fault evaluation
Multicolour LED status display
Remote signalling via freely programmable relays
Sigma Explorer Software: Commissioning and parameterisation via front accessible USB port

Your advantages

Immediate detection of fault direction
No auxiliary supply required
Fast commissioning and parameterisation
Monitoring on site with USB and notebook

Technical specifications

Earth fault detection methods	Earth short-circuit
Low-impedance/short-term low-impedance earthed	---
Isolated earthed	---
Resonant earthed	-
Short-circuit trip current	DIP: 200, 300, 400, 600, 800, 2,000 A, self-adjustment, SW: 50 - 2,000 A
Response delay short-circuit	DIP: 40, 80 ms, SW: 40 ms - 60 s
Earth short-circuit trip current	DIP: off, 20, 40, 60, 80, 100, 120, 160 A SW: 20 - 1,000 A
Response delay earth short-circuit	DIP: 80, 160 ms SW: 40 ms - 60 s
Trip current transient method	-
Trip current active current cos ɸ	-
Response delay active current cos ɸ	-
Trip current reactive current sin ɸ	-
Response delay reactive current sin ɸ	-
Trip current permanent earth fault	-
Response delay permanent earth fault	-
Trip current pulse detection	-
Phase currents	±3 % (0 – 630 A, resolution 1 A) ±5 % (630 – 1,500 A) ±10 % (1,500 – 2,000 A)
Voltages	-
Indication	Short-circuit: 3 red LEDs (L1, L2, L3), 1 red LED I>>; earth fault: 3 red LEDs (L1, L2, L3), 1 red LED IE>; directional arrows red/green
Relay contacts	4
Remote contact	Potential-free permanent or momentary contacts (1 s), NC or NO Contact capacity: 230 V AC/1 A/62.5 VA max. 220 V DC/1 A/60 W max.
RS485/Modbus-RTU	-
USB port	---
Binary inputs	-
Ethernet interface	-
Resistive	-
Capacitive	---
Manual	---
Remote	-
Software via USB	---
Manual reset	---
Remote reset	---
Automatic time reset	---
Reset via interface	-
Reset on current restoration	---
Reset on voltage restoration	---
Reset on restoration of auxiliary supply	-
Reset via Explorer Software	---
Internal power supply	Long-life lithium cell, active flashing time >900 h, shelf life ≥20 years
External auxiliary supply	-
CT powered	---
Housing	Polycarbonate, IP40
Temperature range	-30 to +70 °C
Cable diameter	-