Control & HMI Littelfuse

The SE-325 Neutral-Grounding-Resistor Monitor is designed for use in resistance-grounded systems operating at voltages up to 25 kV. This device plays a critical role in monitoring the integrity of the neutral-to-ground path by measuring the current and voltage at the transformer or generator neutral-to-ground connection. Furthermore, it assesses the continuity of the neutral-grounding resistor (NGR).By coordinating these essential measurements, the SE-325 can effectively identify various issues, including loose connections, corrosion, ground faults, or failures in the NGR. In response to such conditions, it is equipped to provide a single alarm or trip output contact. The device is approved by CSA and operates at a supply voltage of 240 VAC, making it suitable for a range of industrial applications.

The SE-330 is designed for comprehensive monitoring of neutral-grounding resistor systems, ensuring compliance with Rule 10-302 of the 2018 Canadian Electrical Code Part I. This relay continuously measures neutral current, neutral-to-ground voltage, and neutral-to-ground resistance, providing crucial oversight of the neutral-to-ground path.An intact neutral-grounding resistor (NGR) is essential for proper ground-fault protection; any interruption can lead to a false sense of system integrity. Specifically, if the NGR is open, the ground-fault protection may become inoperative, while a shorted NGR could result in abnormally high ground-fault current levels.Suitable for use with both low- and medium-voltage transformers and generators with varying resistance grounding, the SE-330 serves applications across various industries, including processing, manufacturing, chemical, pulp and paper, petroleum, and water treatment facilities. For high-voltage requirements, the SE-330HV is recommended, and for compliance with Australian standard AS/NZS 2081.3:2002, the SE-330AU variant is available.

The SE-330HV-25-01 serves as an essential monitoring relay for ground-fault and neutral-grounding resistors. This device continually measures critical parameters such as neutral current, neutral-to-ground voltage, and neutral-to-ground resistance. Its primary function is to ensure that the neutral-grounding resistor (NGR) remains intact, which is vital for maintaining operational safety. If the NGR is open, it compromises the ground-fault protection system, potentially leading to erroneous assumptions about system integrity. Suitable for both low- and medium-voltage transformers and generators, the SE-330HV-25-01 can be utilized in a variety of sectors including processing, manufacturing, chemical, pulp and paper, petroleum, and water treatment facilities. For high-voltage applications, this model is specifically designed to meet those demands. It conforms to multiple standards, including approvals from CSA, UL, CE, and C-Tick, ensuring reliability across various installations. The device features an analog output current range of 4-20 mA and offers communication options via USB and dual SC Fiber Ethernet. With dimensions measuring 8.4 inches in height, 3.9 inches in width, and 5.8 inches in depth, the SE-330HV-25-01 is designed to fit compactly within control systems.

The SE-330HV-20-01 serves as a vital monitoring relay for ground-fault and neutral-grounding-resistor applications. It continuously assesses the neutral-to-ground path ensuring that the neutral-grounding resistor (NGR) remains intact, which is essential for maintaining effective current-sensing ground-fault protection. An open NGR could lead to system malfunctions, giving a false impression of operational safety.This model is compatible with both low- and medium-voltage transformers and generators, accommodating various grounding configurations across multiple industries, including manufacturing, chemical processing, and water treatment. For applications demanding compliance with the Australian standard AS/NZS 2081.3:2002, the SE-330AU variant is available. The SE-330HV is particularly suited for high-voltage requirements.Technical specifications include an analog output current range of 4-20 mA, with relay contacts available in multiple forms: one Form A, one Form B, and two Form C. It operates on a supply voltage ranging from 28-52 VAC and 36-72 VDC. Communication is facilitated via USB, and the relay contact operating mode is configurable between fail-safe and non-fail-safe. The dimensions of the unit are 8.4 inches in height, 3.9 inches in width, and 5.8 inches in depth.

The SE-330HV Series functions as a sophisticated monitoring relay that assesses the integrity of the neutral-to-ground path. It continuously evaluates neutral current, neutral-to-ground voltage, and neutral-to-ground resistance to ensure the neutral-grounding resistor (NGR) remains intact. An open NGR compromises ground-fault protection, potentially leading to incorrect assessments of system functionality.This relay is suitable for use with both low- and medium-voltage transformers and generators, accommodating low- or high-resistance grounding in various applications, including processing, manufacturing, chemical production, pulp and paper, petroleum, and water treatment facilities. For high-voltage applications, the SE-330HV is recommended. Additionally, for compliance with Australian standard AS/NZS 2081.3:2002, the SE-330AU variant is available.With dimensions of 8.4H x 3.9W x 5.8D, the device provides a range of specifications that include an analog output current of 4-20 mA, relay contacts with one Form A, one Form B, and two Form C configurations, and a supply voltage range of 65-265 VAC and 85-275 VDC. It also features USB communication and has received multiple approvals including CSA, UL, CE, and C-Tick.

The D0920 Arc Detection Unit is a high-speed arc-detection device for electrical power-distribution systems. The D0920 supports up to three point sensors (A0220) mounted in a switchboard, and requires a 230 Vac supply. On the occurrence of an arc fault, the D0920 detects the fault and pulses the trip output in less than 1 ms. The fast trip time reduces the risk of personal injury and equipment damage. The D0920 is typically supplied from the switchboard main power. The AC voltage may fail when an arc fault develops. The D0920 uses energy stored in an internal capacitor to trip the circuit breaker. The storage capacitor is an extremely long-life electrolytic capacitor with a specified life time of more than 30 years at an ambient temperature of 50°C (121°F). The trip energy stored is sufficient for circuit breakers with a 220/250 Vdc shunt trip coil. The D0920 has one output indication relay with an isolated normally-open contact, and one output indication relay with an isolated normally-closed contact. Additional features include power and trip indication, test mode, and sensitivity adjustment.