ABB REM615, REM620, REM630 Motor Protection Relays

Short answer

The REM615 is the motor protection and control relay of ABB's Relion 615 series, for induction motors in industry. The REM611 covers basic applications, the REM620 adds motor differential and more temperature inputs, and the REM630 manages medium and large synchronous and induction motors. All are configured with PCM600 and integrate over IEC 61850.

What it is and where it is used

The ABB REM615 relay is the motor protection and control of the Relion 615 series. ABB presents it for induction motors in manufacturing and process industry: pumps, fans, compressors, mills and conveyors. Alongside it are the REM611, the REM620 and the REM630, its relatives on the same platform.

It is installed in the medium-voltage switchgear of the motor starter or breaker, with conventional current transformers or sensors. For context, see induction motor and its protections.

Variants: REM611, REM615, REM620 and REM630

Model	Application	Main difference
REM611	Small motors and basic applications	Essential motor functions in the 611 series
REM615	Medium-voltage induction motors	Standard configurations from basic protection up to voltage and frequency
REM620	Medium and large induction motors	Adds motor differential (87M), more RTD inputs and an arc protection option
REM630	Medium and large synchronous and induction motors	Full management of the motor and its drive, in the 630 series

There is an IEC edition and an ANSI edition. The standard configuration chosen in the order code defines the available functions.

Main functions

Function	ANSI	What it adds
Motor thermal image	49M	Stator and rotor overload (guide)
Start supervision and locked rotor	48, 51LR	Long starts or a jammed rotor
Load jam and loss of load	50/51J, 37	Process problems
Unbalance and phase sequence	46, 47	Open phase or phase reversal (46 guide)
Overcurrent and ground fault	50/51, 50N/51N	Short circuits in the motor and the cable
Motor differential (REM620, REM630)	87M	Internal faults in large motors (guide)
Voltage and frequency (depending on configuration)	27, 59, 81	Abnormal grid conditions

Communications and integration

Like the rest of Relion, the REM615 integrates over IEC 61850, with GOOSE messages and PRP and HSR redundancy in the dual-port versions, as well as Modbus, DNP3 and IEC 60870-5-103. In industrial plants it is common to integrate it into the process control system over Modbus TCP or IEC 61850. The tool is PCM600.

REM615: standard configurations A, B and C

The REM615 product guide (document 1MRS756890, product version 3.0) defines it as an IED dedicated to induction motors in manufacturing and process industry, of the 615 series, compact and with a withdrawable design. It is offered in three standard configurations:

A: motor protection, with optional RTD/mA inputs.
B: the above plus current, voltage and frequency functions, with optional RTD/mA.
C: like B, with current, voltage and frequency measurement, without the RTD/mA option.

All include thermal overload, start-time supervision, locked rotor, limitation of frequent starts, non-directional ground fault, negative-sequence unbalance, backup overcurrent, stall while running, loss of load and phase reversal. Configurations B and C add directional ground fault, three-phase undervoltage, negative-sequence overvoltage, positive-sequence undervoltage and frequency protection (overfrequency, underfrequency and rate of change).

There are application details that ABB documents and that are easily overlooked:

With cable-type current transformers (CTs), ground fault is sensitive. With phase CTs in Holmgreen (summation) connection, unwanted ground trips can occur when the motor starts because of CT saturation. The relay can avoid them with its internal blocking or with a stabilizing resistor in the common return.
The optional RTD/mA module allows up to eight analog signals: six RTD inputs or two mA inputs. It serves for bearing, stator winding and ambient cooling air temperature, and the values can be shared with other IEDs through analog GOOSE.
There is a forced-start function, for cases where a hot motor in a critical process must start even though the thermal protection prevents it. It is an operating decision that must be foreseen in the procedure and not in an improvised setting.
The arc sensor interface, with three light-detection channels, is available in the optional communication module.
To prevent several motors from starting at once and pulling the voltage down, the start signals of each relay can be cross-wired to the restart-inhibit inputs of the others.

REM630: medium and large motors, synchronous and induction

The REM630 application manual (1MRS756785, revision C, product version 1.1) describes it as a motor management IED for medium and large motors, synchronous or induction, of the 630 series. It is used with breaker- or contactor-controlled drives, and stands out for its configurability. Some data from the manual:

Preconfigurations: an A for an induction motor and a B for an induction motor with differential protection.
Differential: three-phase stabilized differential protection for motors and generators, and high-impedance or balanced-flux differential. In version 1.1 the stabilized differential is optional.
Synchronous motor: optional additional functions, such as directional power, underexcitation and rotor ground fault.
Inputs and outputs: the basic variant has 14 binary inputs and 9 binary outputs; with additional BIO modules it reaches 50 inputs and 45 outputs. The 4U case admits up to two additional modules and the 6U up to four.
Analog: modules of 4, 7 or 8 current inputs and 4, 3 or 2 voltage inputs, and an eight-input RTD module.
Communications: IEC 61850, IEC 60870-5-103 (from 1.1), DNP3 and analog GOOSE. The Ethernet connector can be electrical or optical.
Tool: PCM600, version 2.3 or later for that product version.

On the ABB/Hitachi Energy website, the REM630 IEC appears as a product out of active service since 2024. For installed equipment, this means keeping spares and documentation and planning a renewal ahead of time; in our case the help focuses on reviewing the settings and defining the equivalence with a current platform.

Data the relay needs

A motor relay is set with the nameplate data and the thermal curve of the motor: rated current, locked-rotor time cold and hot, starting current and time, and the number of starts allowed. Without that data, any setting is a guess. That is why, before configuring a REM615, we ask for the motor manufacturer’s datasheet and the process information.

Frequently asked technical questions

REM615 motor protection relay and its manual: ABB publishes a product guide, application manual and technical manual by version and edition.
Thermal image trip on starting: repeated or long starts exhaust the thermal capacity. The solution is in the motor and process data, not in raising the setting without a study. See overcurrent trip on starting or energization.
Restart inhibit: the relay prevents a new start until the motor cools; it is a protection, not a fault.
RTD inputs: when there are probes in the stator or the bearings, they must be configured and tested with the correct probe type.

How we help

At Tiza Group we configure and review REM615, REM620 and REM630 relays remotely, worldwide, with PCM600, from the motor data, the study and the approved settings. See the scope in remote configuration of Relion relays. If a motor tripped and you do not know why, we quote a trip analysis. To replace an old motor relay, we do the design in engineering design and studies. Write to us through contact.

References

IEEE C37.2, device numbers; IEEE C37.96, AC motor protection.
IEC 61850 (series).
ABB, REM615, REM620 and REM630 product pages and guides; ABB, Relay Retrofit Program.

Frequently asked questions

What does the REM615 relay protect?

Medium-voltage induction motors in manufacturing and process industry. It includes thermal image, start supervision, locked rotor or stall, loss of load, unbalance and phase sequence, plus voltage and frequency functions in the configurations that include them.

What is the difference between the REM615, REM620 and REM630?

According to ABB, the REM615 is intended for induction motors; the REM620 for medium and large induction motors that need motor differential and more RTD inputs; the REM630 for full management of medium and large synchronous and induction motors. The choice depends on the motor and on the study.

Does the REM615 replace the SPAM 150 C?

ABB includes it in its relay retrofit program: the SPAM 150 C has as its destination a REM615 with a defined standard configuration, or the REX610. Replacement requires transferring settings and reviewing the wiring, even where adaptation kits exist.