RX2E & RX3E Enclosed Combination Soft Starters

Severe Duty Combination Starters for Demanding Applications

The RX2E & RX3E Enclosed Combination Soft Starters provide rugged, reliable motor control with built-in protection, giving precise control over starting and stopping three-phase motors.

Standard features include a circuit breaker, full-voltage emergency bypass contactor, door-mounted Start/Stop push buttons, Local/Off/Remote selector switch, and a door mounted MX2 or MX3 keypad. Available in NEMA 12 or NEMA 3R enclosures, the full-voltage bypass contactor also functions as a running-duty bypass when in soft starter mode.

The RX2E & RX3E can be programmed using a door-mounted LCD keypad or Modbus register mapping.

Request Info

Standard Features

NEMA 12, dual redundant, combination/circuit breaker
Shunt trip on main circuit breaker
500% — 30 seconds rated solid state starter, UL certified and listed
1800 PIV rated SCRs, UL certified and listed
125% continuous duty rated solid state starter, UL certified and listed
Selector switch for selecting solid state or full voltage operation mounted inside enclosure
Full HP rated bypass contactor with a 1.15 service factor, wired for normal bypass operation and full voltage start and run operation, with normally open auxiliary contact
Separately mounted “SPE” series overload relay wired for full voltage start and run operation.
110 volt control power transformer with primary and secondary fuses

Door-mounted start and stop push-buttons
Door-mounted keypad
Door-mounted run indicating light
Door-mounted local-off
remote switch
Door-mounted overload reset
Terminal strip mounted inside enclosure for remote start/stop connection
Auxiliary relay with (2) Form C run contacts
Benshaw MX2 or MX3 programmable motor controller with soft start, soft stop and motor protection capabilities
RS485 ModBus communications
Analog I/O
Available with MX3 technology

MX2 vs MX3 Control Comparison

Benshaw’s MX2 and MX3 control technologies provide the core functionality of the RX2E and RX3E Series Enclosed Combination Soft Starters. MX2 technology delivers basic motor protection with adjustable overload settings, along with user-adjustable motor ramp profiles that can be tailored to the load for smooth acceleration and deceleration, including adjustable voltage control suitable for pumping applications. MX3 technology builds on this by providing advanced motor protection with adjustable overload settings and optional RTD monitoring, eliminating the need for a third-party protection relay. It also includes a real-time clock with an event recorder (up to 99 events), while retaining the same user-adjustable ramping and voltage control deceleration features as MX2.

Feature	MX2	MX3
Starting Modes
Slow Speed / Jogging	7-14%	1-40% (Cyclo™)
Configurable Digital Inputs	3	8
Fixed Digital Inputs	2	2
Configurable Relays	3	6
Fixed Relays	1	1
Motor Protection		+ PTC & RTD Support, zero sequence GF
Metering / Monitoring		+ Real Time Clock
Fault Recorder		+9-event recording
Fixed relay outputs	-	99 events
P.O.R.T (Power Outage Recovery)	-
Analog I/O	1 in / 1 out	1 in / 1 out
LED Interface
Remote LCD	Residual	Residual or zero sequence
Communications		+ real-time clock
Optional Communications Modules	1 input / 1 output configurable	1 input / 1 output configurable
Advanced Ramp Functions
DC Braking	Light	Full
Energy Saver
Remote Keypad Ready

RB Series Open Chassis Starters with Integral Bypass

At the core of every RX2E/RX3E is Benshaw’s RB series solid state starter. The RB Series combines the high performance MX2 or SCRs In Reverse Parallel Configuration NEMA 2-Hole Pattern (bottom entry/ bottom exit) dV/dt Protection NEMA 2-Hole Pattern (top entry/top exit) MX3 technology with a rugged, compact, integral bypass RB series power section.

The MX2 or MX3 technology provides users with a powerful group of programming parameters, designed for flexibility in across a wide range of industrial applications. Both MX2 and MX3 controls provide simple setup and commissioning via the Quick Start Menu.

The RB power section is a rugged, heavy duty solid state starter section designed with integral bypass contactor for a compact, efficient profile. The modular design includes separate poles for each phase for ease of maintenance.

RB2 & RB3

RB Series Key Advantages

Modular power stack assembly for ease of maintenance
ModBus standard/other Fieldbus optional
Multiple starting ramps for various applications
Integrated metering system diagnostics
Fieldbus
Ethernet IP/TCP

Profibus
DeviceNet
Integral bypass contactor for efficient operation, eliminating the need for external fans
Integrated motor protection
Dual ramp capability for loaded/unloaded applications
Power stack has multiple ratings for application flexibility

Motor Protection Features

Feature	RX2E	RX3E
ANSI 14 – Speed switch and tachometer trip
ANSI 19 – Reduced voltage start
ANSI 27 / 59 – Adjustable over/under voltage protection (Off or 1 to 40%, time 0.1 to 90 seconds in 0.1 second intervals, independent over and under voltage
ANSI 37 – Undercurrent detection (Off or 5 to 100% and time 0.1 to 90.0 seconds in 0.1 second intervals)
ANSI 38 – Bearing RTD / Other RTD / Open RTD alarm
ANSI 46 – Current imbalance detection (Off or 5 to 40%)
ANSI 47 – Phase rotation (selectable ABC, CBA, Insensitive, or Single Phase)
ANSI 48 – Adjustable up-to-speed / stall timer (1 to 900 seconds in 1 second intervals)
ANSI 49 – Status RTD
ANSI 50 – Instantaneous electronic overcurrent trip
ANSI 51 – Electronic motor overload (Off, class 1 to 40, separate starting and running curves available)
ANSI 51 – Overcurrent detection (Off or 50 to 800% and time 0.1 to 90.0 seconds in 0.1 second intervals)
ANSI 51G – Residual ground fault detection (Off or 5 to 100% of motor FLA) / zero sequence ground fault detection (Off, 0.1 – 25 amps)
ANSI 66 – Starts/hour and time between starts / restart block (backspin timer)
ANSI 74 – Alarm relay output available
ANSI 81 – Over/under frequency
ANSI 86 – Overload lockout
Shorted SCR detection
Mechanical jam

RX2E/RX3E Series Enclosed Combination Soft Starters