NEW ULM — The New Ulm Public Utilities Commission accepted four proposals from Power System Engineering, Inc. (PSE) for electrical projects.

The first project was to develop plans and specifications, acquire and oversee the replacement of substation relays.

This project will replace obsolete electromechanical relays for the 69kV Unit 4 transformer and bus relaying at the North Side 69kV breaker 5416 relaying, and North Side 13.2 kV unit 3A relaying.

The relays will be replaced with the Schweitzer Engineering Laboratories (SEL) relays, allowing greater data collection and easier maintenance. In the future, the supervisory control and data acquisition (SCADA) system will tie directly into the SEL relays for instantaneous data collection.

Due to the age of the electrotechnical relays, there are few people with the skills to maintain and work on this old technology. This project removes ten relays and replaces them with three. This is the last relay project on the North Side Substation before the North Side Substation Remote Terminal Unit (RTU) replacement project.

The project costs $125,400 but was originally budgeted for $90,000.

The commission also authorized accepting the proposal from PSE to develop plans and specs, acquire and oversee the replacement of the Remote Terminal Unit (RTU) at the Center Street Substation for $105,000 but was budgeted in 2022 for $135,000.

This project replaces the current obsolete RTU, which was designed in 1996. The current system is no longer supported, and its components are no longer available after 2013.

The software does not work on any computers with an operating system newer than Windows XP, which also is no longer supported by Microsoft. The XP operating system has some significant security flaws and is being replaced industry-wide.

New Ulm has two substations configured like this, and the third substation is also outdated and is scheduled to be upgraded as well. The plan for updating is Center Street Substation this year, the North Side Substation in 2023, and the South Side Substation in 2024 or 2025.

PSE’s proposal to develop plans and specs set the bid date, and advertise the bids for the Transmission Line Bypass at Center Street Substation was also approved.

The project design work will entail the line work, pole additions, switch additions and relay modification to allow the bypass of the Center Street Substation.

The current configuration allows the power to flow through the bus work keeping it energized. This design currently forces the center and south substations 69kVA out of service when we need to work on any 69kVA hardware or any of the miscellaneous bus work items at the Center Street Substation.

The replacement of the main Center Street breaker is one of many upcoming projects. This breaker controls two-thirds of the electricity supplying the center and south ends of New Ulm. This project will be done without the need for a generation. Once the design is fully implemented the Center and South substations will be able to operate more independently of one another.

This project is estimated at $71,500 and was budgeted for $400,000.

The final PSE project is the Center Street Substation 69kV breaker upgrades. This project replaces the 2416 breaker manufactured in 1969 by the ITE Imperial Corporation. This breaker is no longer supported by any manufacturer, and any form of breakdown could result in an extended outage while components are being made. This breaker is beyond its practical useful life. The cost of the project is $38,000.

The combined estimate for the four PSE projects is $339,900.

The commission unanimously approved all four proposals.