The components low-resistance or solidly-earthed systems because, in required to monitor an NER are an SE-330AU, an ER-series those systems, an earth-fault flash hazard exists and an sensing resistor, and a current transformer (CT). earth fault can result in substantial point-of-fault damage.
2.1.3 V EVEL When the trip level is set to MEM, the earth-fault trip The SE-330AU uses a DFT algorithm to measure the setting is defined by an internal non-volatile memory fundamental component of neutral voltage (V variable. Range is 2 to 100% in 1% increments of the...
The SE-330AU monitors the continuity of the CT See Section 6.1. circuit. When an open CT circuit is detected for two 2.1.7 G seconds, the SE-330AU will trip on earth fault and the AGNETIC ILTER diagnostic LED will flash the CT-Detection-Error code.
When a trip occurs with latching operation selected, the include SD Card status and USB Error status. All other SE-330AU remains tripped until reset with the front panel diagnostic codes are considered critical. button or the remote-reset input. See Sections 2.1.4.1 and Starting with SE-330AU firmware version 2.60 and...
Page 5 SE-330AU Neutral-Earthing-Resistor Monitor Rev. 4-I-101817 TABLE 1. T YPICAL ALUES FOR RIPPING YSTEMS SYSTEM VOLTAGE NEUTRAL-EARTHING EARTH-FAULT TRIP LEVEL (VOLTS) RESISTOR (AMPERES) SENSING TRIP LINE TO LINE TO CURRENT RESISTANCE EFCT-X SE-CS30-X RESISTOR LEVEL (30-A LINE NEUTRAL (AMPERES)
Outline and panel-cutout dimensions for the SE-330AU unlikely, a minimal loss of protection will result if it does are shown in Fig. 4. To panel mount the SE-330AU, not pass through the earth-fault-CT window. See Fig. 3. insert it through the panel cutout and secure it with the : Voltage at terminal N rises to line-to-neutral voltage four included 8-32 locknuts and flat washers.
ONNECTION Isolated earthing can prevent an earth potential rise (EPR) from being transferred to remote equipment. If the G terminals on the sensing resistor and the SE-330AU are connected to isolated earth, the SE-330AU will be exposed to the EPR.
Do not remove and 8) – also includes Modbus TCP the SD card or power off the SE-330AU until the Refer to the appropriate SE-330 communications-interface DIAGNOSTIC LED has stopped blinking rapidly for at least 30 seconds.
: ON, RF LED : ON, K1:Trip CT-Detection-Error Trip 1 L - 3 S - 1 L The CT connection to the SE-330AU is open. Correct the problem DIAGNOSTIC LED flash code and press RESET. Critical diagnostic code. A/D-Converter-Error Trip 1 L - 4 S - 1 L An A/D-converter error was detected.
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: No Change, RF LED : No Change, K1:No Change DIAGNOSTIC LED = Solid Red SE-330AU processor failed to start. Cycle supply. If problem persists, consult Littelfuse Startco. K1: De-energized. Pressing RESET does not clear trips. Trip condition is still present. Locate and correct.
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Page 29 SE-330AU Neutral-Earthing-Resistor Monitor Rev. 4-I-101817 Ratings ........100 mA, 250 V (ac or dc) Environment: Closed Resistance ....30 to 50 W Operating Temperature ..-40 to 60°C (-40 to 140°F) Storage Temperature ..... -55 to 80°C (-67 to 176°F) Humidity ........
OTE: Insulation ......600-V Class (PCN) document for updated ordering information and new Window Diameter ....82 mm (3.2”) revision details, available at www.littelfuse.com/se-330au. Shipping Weight ....0.9 kg (2.0 lb) Certifications ....... CSA, UL, CE OTE: The SE-330-SMA Surface Mount Adapter is Compliance ......
Littelfuse Startco will (at Littelfuse Startco’s option) repair, replace, or refund the original purchase price of an SE-330AU that is determined by Littelfuse Startco to be defective if it is returned to the factory, freight prepaid, within the warranty period. This warranty does not apply...
Test Equipment: 0 to 120 Vac voltage source, multimeter, and ER sensing resistor. Use an isolation transformer if the test-voltage source does not provide dc continuity for the SE-330AU resistance-measuring circuit. : Applying the test voltage to the R and G terminals will damage the SE-330AU and the ER sensing resistor.
This check can be done visually with knowledge of the circuit. connection of the current-sensor secondary to the SE-330AU is not polarity sensitive. c) Verify that the system is correctly earthed and that alternate earth paths do not exist that bypass the current sensor.