PRODUCT PARAMETERS

A 5.5KW~400KW medium-to-high power, intelligent bypass soft starter for industrial three-phase scenarios. Ideal for high-demand equipment like large pumps, fans, conveyors, crushers, and power plant auxiliary drives.

Triple Start Modes
Bypass Design for Energy Efficiency
Comprehensive Protection System
Robust Environmental Adaptability
Intelligent Integration
Flexible Installation

REQUEST A QUOTE

Description

FAQs

Request A Quote

Description

Product Overview

The ZHR8 Series Bypass Soft Starter (Bypass Intelligent Motor Soft Starter) is an advanced digital soft starting solution, tailored for medium-to-high power three-phase AC asynchronous motors. As a core Bypass Soft Starter, it automatically switches to bypass operation after start-up completion, reducing thyristor loss and improving long-term operation efficiency.

This intelligent motor soft starter supports three start modes (voltage ramp start, current-limiting start, torque start) and two stop modes (free stop, timed soft stop). As a professional online soft starter (configurable), it is equipped with 10+ core protection functions, including input phase loss, output phase loss, overload, overcurrent, overvoltage, undervoltage, underload, overheating, phase sequence error, and thyristor breakdown protection. It supports RS485 communication (Modbus-RTU protocol) and Chinese/English dual-language display, adapting to 220V/380V voltage levels and star connection methods. With IP20 protection level and forced air cooling, this industrial motor soft starter ensures stable operation in harsh industrial environments (-10℃~40℃).

Its core design focuses on high reliability, energy efficiency, and easy maintenance. Through optimized bypass circuit layout and heat dissipation structure, this Bypass soft starter meets the continuous operation demands of critical equipment such as large pumps, fans, and conveyors in medium-to-high power scenarios requiring a reliable soft starter.

Applications

The ZHR8 Series Bypass Industrial Soft Starter is widely applied in medium-to-large industrial scenarios, heavy-load operations, and key infrastructure, providing stable soft start solutions for equipment with high starting torque and power requirements as a professional motor soft starter:

Heavy Industry & Metallurgical Auxiliaries

Medium-sized non-ferrous metal processing equipment powered by Bypass Soft Starter
Ore crushers, ball mills, and mineral processing machinery equipped with motor soft starter
Metallurgical hoisting tools, ladle transfer equipment matched with online soft starter
Steel processing auxiliary drives supported by soft starter

Mining & Construction Materials

Mine belt conveyors with dedicated conveyor soft starter (a type of in-line soft starter)
Cement mill drives, rotary kiln auxiliary equipment powered by Bypass Soft Starter
Stone crushers, sand making machines equipped with motor soft starter
Construction tower crane auxiliary drives supported by soft starter

Water Treatment & Environmental Protection

Large sewage lifting pumps with specialized pump soft starter (matched with Bypass Soft Starter)
Industrial aeration blowers equipped with fan soft starter (a type of motor soft starter)
Chemical dosing pumps powered by pump soft starter (supported by online soft starter)
Desalination plant high-pressure pump drives with soft starter

Chemical & Petroleum Industry

Chemical reactor agitator drives equipped with Bypass Soft Starter
Oil drilling rig auxiliary pumps powered by motor soft starter
Large air compressors, reciprocating pumps with pump soft starter (a type of in-line soft starter)
Pipeline transportation pump drives supported by soft starter

Power & New Energy Auxiliaries

Small power plant boiler feed pump drives with Bypass Soft Starter
Solar energy storage system auxiliary motors equipped with motor soft starter
New energy vehicle production line heavy-duty conveyors with conveyor soft starter (powered by online soft starter)
Wind turbine auxiliary drive equipment supported by soft starter

Agriculture & Food Processing

Large agricultural machinery (combine harvesters, tractors) equipped with Bypass Soft Starter
Grain drying equipment drives powered by motor soft starter
Large feed grinder, mixer drives matched with bypass soft starter
Food processing line auxiliary machinery supported by soft starter

Product Features

Bypass Design for Energy-Saving Operation (Bypass Soft Starter)

As a professional Bypass Soft Starter, it automatically switches to bypass operation after start-up, avoiding continuous thyristor heating loss, reducing energy consumption, and extending the service life of this motor soft starter.

Triple Start Modes, Adapt to Diverse Loads (Motor Soft Starter)

This soft starter supports voltage ramp start (smooth start for general loads), current-limiting start (grid protection for high-impact loads), and torque start (high-torque start for heavy loads). It flexibly matches different equipment characteristics, making it an ideal online soft starter for diverse scenarios.

Comprehensive Protection System, Safe & Reliable (Bypass Soft Starter)

This in-line soft starter integrates 10+ core protections including input/output phase loss, overload, overcurrent, overvoltage, undervoltage, underload, overheating, and phase sequence error. Dual overload protection (inverter + motor) avoids equipment failure under heavy loads, ensuring operational safety for this Bypass Soft Starter.

Intelligent Communication & Centralized Control (Soft Starter)

Equipped with RS485 communication interface and Modbus-RTU protocol, this motor soft starter supports remote start/stop, parameter adjustment, and fault monitoring. It facilitates centralized management of multiple devices, improving on-site operation efficiency for online soft starter users.

Dual-Language Display & Intuitive Operation (Motor Soft Starter)

This Bypass Soft Starter supports Chinese/English bilingual operation interface, with detachable operation panel and clear LED status indicators. Parameter setting is simple, and fault codes are displayed intuitively for quick troubleshooting of this soft starter.

Pump-Specific Custom Functions, Scenario Optimization (Soft Starter)

This motor soft starter supports 4 pump-matching functions (float switch, electric contact pressure gauge, water supply/drainage liquid level relay), optimizing start-stop logic for water supply/drainage systems. It realizes automatic operation of pump equipment, making it a professional pump soft starter under the Bypass Soft Starter category.

Flexible Installation & Strong Expandability ( Bypass Soft Starter)

This soft starter supports wall-mounted installation and cabinet-type installation (soft starter cabinet), adapting to different on-site space requirements. Optional programming relays and 4-20mA analog output meet personalized expansion needs for online soft starter applications.

Specifications

Basic Information	Model Series	BK-ZHR8 Series
	Type	Bypass-Type Intelligent Soft Starter (Solid-State, 6 SCR Full-Wave Control + External Bypass Contact)
	Applicable Motor	Squirrel-cage Three-phase Induction Motor
	Power Range	220V System: 5.5 kW – 220 kW 380V System: 5.5 kW – 400 kW
	Rated Current	11A – 800A (User-settable via F00)
	Connection Method	Line (Star/Y) connection only
Electrical Characteristics	Input Voltage	220V / 380V AC ±15% (Three-phase)
	Input Frequency	30 Hz – 70 Hz (Auto-adaptive)
	Control Power	Built-in (No external 24V required for control logic)
	Output Voltage Control	Phase-angle control via thyristors during start/stop
Control & Operation	Start Modes	• Voltage Ramp (Default) • Current Limiting • Torque Control
	Stop Modes	• Free Stop • Timed Soft Stop (0–60 s adjustable)
	Start Time	1 – 120 s
	Start Current Limit	50% – 600% of motor rated current (Ie)
	Initial Voltage	30% – 80% Ue
	Maintenance Voltage	60% – 85% Ue (F08)
	Early/Late Acceleration	Adjustable (F09, F11)
Protection Functions	Built-in Protections	• Input Phase Loss • Output Phase Loss • Overload (Class 1–30) • Start Overcurrent • Run Overcurrent • Overvoltage • Undervoltage • Underload • Phase Sequence Error • Current Unbalance • Module Overheat • External Fault Input • Thyristor Breakdown
	Protection Response	Configurable: Trip or Ignore (via F41–F49)
	Overload Curve	IEC Standard Inverse-time (Adjustable Class 1–30 via F21)
Control & I/O	Digital Inputs	3 Programmable (IN1, IN2, IN3) + 24V COM Functions: Start, Stop, External Fault
	Relay Outputs	Relay 1: TA1/TB1/TC1 (Common/NC/NO) Relay 2: TA2/TC2 (NO only, optional)
	Relay Functions	Selectable: Power-on, Soft-start, Bypass, Soft-stop, Running, Standby, Fault
	Analog Output	1 Channel: 4–20mA (Scalable 50%–500% Ie via F17)
	Communication	RS485 (Modbus RTU Protocol) • Baud Rate: 2400/4800/9600/19200 bps (default 9600) • Address: 1–127
User Interface	Display	LCD with Backlight (Chinese / English)
	Keypad	Local Start/Stop, Parameter Setting, Fault Reset
	LED Indicators	READY (Standby), RUN (Start/Run/Soft-stop), TRIP (Fault), LOCAL
Mechanical & Environmental	Cooling Method	Forced Air Cooling (Built-in fan)
	Protection Degree	IP20 (For installation in electrical cabinet only)
	Mounting	Wall-mounted (Screw mounting, M6/M8 per size)
	Operating Temperature	-10°C to +40°C Derating required above 2000m altitude
	Humidity	≤95% RH, non-condensing
	Vibration	< 0.5G
Compliance & Safety	Standards	Designed per IEC 60947-4-2 principles
Compliance & Safety	Safety Notes	• STOP function does NOT isolate output voltage. • External safety disconnect required before maintenance. • Not suitable for emergency stop circuits. • Bypass contactor must be installed externally (see terminal L21/L22/L23).
Additional Features	Pump Control Modes	5 Modes: 0: None 1: Float Switch 2: Pressure Switch 3: Supply Level Relay 4: Drain Level Relay
	Language Selection	Chinese (Default) / English (F50)
	Soft Starter Type	Configurable: Online (F52=0) or Bypass-type (F52=1, Default)
	Monitoring Parameters	Real-time display of: • Output current (Ir) • Input voltage • Fault history • Running status

Model Comparison Chart

ZHR8 Series (Bypass Soft Starter)	Voltage Level	Power Range (KW)	Rated Current (A)	Overall Dimensions (mm) W1H1D	Mounting Hole Size (mm)
ZHR8-5.5KW~160KW	220V/380V	5.5~160	11~150	145314157	M6
ZHR8-180KW~250KW	380V	180~250	180~230	201321.5182	M8
ZHR8-264KW~350KW	380V	264~350	264~400	225393226	M8
ZHR8-370KW~400KW	380V	370~400	440~800	353547.4265	M8