When I took over electrical equipment purchasing in 2020, one of the first decisions I had to make was about protection relays. The engineering team was split: half wanted the latest GE Multilin 850 series, the other half insisted on traditional electromechanical or basic digital relays. I didn't have an electrical engineering background (note to self: learn the basics fast). So I had to approach this as a procurement problem: what delivers the best value, reliability, and maintainability for our specific needs?
This comparison breaks down the key differences between GE Multilin protection relays (specifically the 845 and 850 series) and traditional protection schemes. I'm writing this from the perspective of someone who manages the buying process, not the design spec. If you're an engineer, some of this will be familiar ground. But if you're the person who has to justify the cost and manage the vendor relationship, this should help.
Why This Comparison Matters
Most buyers focus on the upfront cost per unit and completely miss the total cost of ownership. The question everyone asks is, 'Which one is cheaper?' The question they should ask is, 'Which one costs less over 10 years including installation, commissioning, maintenance, and potential failure costs?'
Here's the thing: the difference between a $1,500 GE Multilin 845 and a $300 traditional relay is not just a number on a purchase order. It's a fundamentally different approach to protection, monitoring, and asset management.
Dimension 1: Functionality & Protection Scope
GE Multilin 845/850: These are numerical, multi-function relays. A single 850 can handle overcurrent, differential (87T), voltage, frequency, and arc flash protection—all in one device. You configure what you need via software. It's a platform.
Traditional schemes: You need separate relays for each function. Overcurrent relay here, differential relay there, voltage relay somewhere else. Each one is a separate device with its own wiring, its own test requirements, and its own failure point.
My take: The Multilin approach simplifies your panel design and reduces wiring complexity. But—and this is a big but—you're putting a lot of trust in one device. If that 850 fails, you lose multiple protection functions at once. Traditional schemes are more fault-tolerant in that sense: one relay fails, you still have other protection layers.
The reality: for most substations and medium-voltage applications, the reliability of modern numerical relays has made this a non-issue. I've seen fewer failures on Multilin relays than on electromechanical ones (which have moving parts that wear out). But I also carry a spare unit, just in case.
Dimension 2: Commissioning & Configuration
GE Multilin 845/850: Configurable via GE's Enervista software. You set parameters, logic, and communications on a laptop. Changes can be made remotely if the relay is networked. Commissioning is faster once the settings are finalized, but the initial setup requires trained personnel who understand the software and the protection logic.
Traditional schemes: Hardwired logic. You set pickup values and time dials physically on the relay face. Changes require someone to go to the panel, open it, and adjust DIP switches or potentiometers. Simple, but inflexible.
My take from a procurement standpoint: The Multilin approach means you need a more skilled contractor for initial setup. That costs more upfront—maybe $500-1,000 extra in engineering time per relay. But I've found that the ability to make changes remotely has saved us thousands in truck rolls. In 2023, we had a coordination study change that required new settings. With Multilin relays, the engineer updated the file remotely and emailed it. If we'd had traditional relays, a technician would have visited each of three sites to adjust dials.
As of January 2025, I'd estimate our average commissioning time for a Multilin 850 is 4-6 hours including software setup. A traditional scheme of equivalent functionality (multiple individual relays)? Probably 8-12 hours of panel wiring and testing. The savings become clear.
Dimension 3: Monitoring & Diagnostics
GE Multilin 845/850: Each relay is also a monitoring device. It tracks breaker operations, trip coil health, arc flash energy, and event logs. You can integrate with SCADA or a local monitoring system to get real-time data. The 850 series even offers transformer monitoring features that compete with dedicated monitor brands.
Traditional schemes: You get a trip signal and maybe a target flag. That's it. For anything more, you need separate monitoring equipment—which adds cost and complexity.
My experience: The monitoring capability was the deciding factor for us. In Q3 2024, one of our Multilin 845 relays recorded a series of breaker operations that showed an emerging problem. Event logs showed tripping patterns. We caught a failing mechanism before it caused a catastrophic failure. That single event probably saved us $15,000 in unplanned downtime—more than the cost of all the Multilin relays we'd bought that year.
A traditional scheme wouldn't have given us that data. Period. The question everyone asks is, 'What's the cost?' The question they should ask is, 'What's the cost of not having the data?'
Dimension 4: Communications & Integration
GE Multilin 845/850: Built-in Ethernet, Modbus TCP, DNP3, IEC 61850 support. They talk to your SCADA system, your local HMI, and even your cloud-based monitoring platform. Firmware updates can be applied remotely.
Traditional schemes: Maybe a contact closure to a PLC. No protocol support. No remote data. If you want remote status, you need external I/O modules.
The procurement reality: If your facility is moving toward digitalization or Industry 4.0, Multilin relays are a no-brainer. They're an asset on the network, not an island. However, if you have a simple, non-critical feeder that just needs basic protection, adding a Multilin relay with full communications is overkill. I've seen buyers overspend by putting a fully instrumented 850 on a non-critical 480V feeder where a simple $200 overcurrent relay would suffice.
So Which One Should You Choose?
Here's my practical, scenario-based advice after managing electrical equipment procurement for 5 years:
Choose GE Multilin 845/850 when:
- You need multiple protection functions in a single device (especially transformer differential 87T)
- You want monitoring and event logging for asset management
- You're integrating with a modern SCADA or digital substation
- You have trained personnel who can configure and maintain them
- Your facility values uptime and data-driven maintenance
Choose traditional schemes when:
- You only need basic overcurrent protection on a non-critical load
- Your facility has minimal monitoring requirements
- You want maximum simplicity and ease of replacement
- Your maintenance team is more comfortable with hardwired logic
- Budget is extremely tight for a specific feeder or panel
The honest truth: Most of our projects now use a hybrid approach. Critical transformers and feeders get GE Multilin 845 or 850 relays (the 850 for large power transformers where differential protection is essential). Non-critical loads get simpler relays. But even then, I've found that the price gap between a basic digital relay and a Multilin 845 has narrowed. As of January 2025, the 845 starts around $1,200-1,500 for basic configurations. When you factor in the monitoring capabilities and reduced wiring costs, it often makes economic sense even for moderate applications.
I'd rather spend 15 minutes explaining options than deal with mismatched expectations later. An informed buyer asks better questions and makes faster decisions. Based on quotes we received in Q4 2024, expect to pay $1,500-3,000 for a fully-configured GE Multilin 850, and $200-600 for a comparable traditional overcurrent relay. The premium is significant. But for critical applications, the return on that investment shows up in avoided downtime and better data.
Pricing is for general reference only. Actual prices vary by vendor, specifications, and time of order. Verify current pricing with your GE representative or authorized distributor.
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