Neutral-Earthing-Resistor Monitor by Littelfuse

The SE-330AU is an advanced earth-fault and earthing-resistor monitoring relay for low- and medium-voltage transformers and generators. It monitors neutral current, neutral-to-earth voltage, and neutral-to-earth resistance. It provides continuous monitoring of the neutral-to-earth path to verify that the neutral-earthing resistor (NER) is intact. This is of utmost importance;an open NER renders current-sensing earth-fault protection inoperative and could result in a false belief that the system is functioning properly. The SE-330AU earth-fault function complies with AS/NZS 2081.3:2002. For non-AS/NZS 2081 applications, see the SE-330 or SE-330HV. The SE-330AU New Revision provides these additional features: 100 trip records with date and time stamp, A mini-USB interface to view measured values, configure settings and check event records using SE-MON330 v3.2 or later, An on-board microSD card (included) can be used for long term data logging and firmware upgrades, Earth-fault trip level is adjustable from 0.125 to 5A (EFCT) or 0.75 to 30A (CS30). When set to MEM, the earth-fault trip level is adjustable from 2 to 100% in 1% increments of the CT-primary rating. SE-MON330 V3.2 or later is required. Dual Ethernet ports are optionally available with support for fiber and RJ45 interfaces. Connect the SE-330AU to the network using a standard Ethernet patch cable. Use of a crossover cable to connect the SE-330AU 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 SE-330AU does not support the use of DHCP. If the SE-330AU is being set-up for first time, it is recommended to only have one SE-330AU connected to the network to prevent communication errors.