Product Overview

The GE Multilin 369-HI-R-M-0-0​ is a digital motor management relay from GE’s Multilin 369 series, engineered to protect, control and monitor three-phase medium-sized AC motors and the mechanical equipment they drive. The order code describes the unit precisely: 369 is the base platform, HI denotes the wide-range control power supply accepting 50–300 V DC or 60–265 V AC, R adds twelve built-in three-wire RTD inputs, M adds the full metering package, and the two trailing zeros mean no fibre-optic port and no optional protocol interface beyond the standard serial set. In short, the 369-HI-R-M-0-0​ is the fully specified, serial-communications configuration of the platform — the variant chosen when a motor needs genuine thermal supervision from embedded winding sensors as well as electrical metering at the relay itself.At the centre of the GE Multilin 369-HI-R-M-0-0​ is an enhanced thermal model that continuously tracks thermal capacity used, updating every tenth of a second. Unlike a simple inverse-time curve, this model accepts bias from negative-sequence current and from RTD-measured temperature, uses separate cooling time constants for running and stopped conditions, and can learn a specific motor’s inrush current, acceleration time and cooling rate so that protection matches the machine rather than a generic assumption. Overload protection can follow any of fifteen standard curves or a user-drawn FlexCurve.Around that core, the 369-HI-R-M-0-0​ carries the full complement of motor protection: short circuit, ground fault, stall and mechanical jam, current unbalance and single-phasing, undercurrent, undervoltage, overvoltage, underfrequency and phase reversal, plus start supervision covering starts per hour, time between starts and acceleration timeout. Because the M option is fitted, the relay also measures voltage, real and reactive power, power factor, frequency and energy, and provides four analogue outputs for driving external indicators or a DCS.

Technical Specifications

Main Features and Advantages

Thermal model that mirrors the actual machine: The GE 369-HI-R-M-0-0​ does not guess at motor heating. It maintains a running thermal capacity calculation that is biased by measured negative-sequence current, which is the component responsible for rotor heating and the one motor manufacturers’ curves rarely account for, and by real RTD temperatures where those are fitted. Separate cooling time constants apply while the motor runs and while it stands still, so a hot restart after a trip is judged on honest thermal state rather than a fixed timer. The relay also learns each machine’s inrush current, acceleration time and cooling rate, tightening protection over successive starts.Twelve RTD inputs that convert temperature into protection: With the R option, the 369-HI-R-M-0-0​ accepts twelve three-wire RTDs with the sensor type software selectable, so stator windings, drive-end and non-drive-end bearings, ambient air and even the driven equipment can be supervised from one device. Each input carries alarm, high-alarm and trip thresholds, and open or shorted sensor wiring is detected and annunciated rather than silently corrupting the thermal model.Diagnostics that explain the trip, not just record it: A motor trip with no explanation costs hours. The GE Multilin 369-HI-R-M-0-0​ stores the last 512 events with cause and data at the moment of trip, captures oscillography of phase current, ground current and contact input status, and logs thirty seconds of waveform during motor starting so that acceleration problems can be diagnosed. The Motor Health Report and the security setting-change history give maintenance teams and auditors a documented view of what the motor and the relay have been through.Metering and communications without extra hardware: Because the M option is installed, the 369-HI-R-M-0-0​ measures voltage, power, power factor, frequency and energy directly and offers four analogue outputs, so a DCS can trend motor load without a separate transducer. Three independent isolated RS485 ports plus a front RS232 port allow local commissioning and plant network integration to run simultaneously, all over Modbus RTU.