Integrated Bypass Soft Starter丨BK-ZHR10 Series (135KW-400KW)

Product Overview

The ZHR10 Series Integrated Bypass Soft Starter (Built-in Bypass Intelligent Motor Soft Starter) is an advanced digital soft start solution, suitable for 0.37~400KW three-phase AC asynchronous motors. As a core Bypass Soft Starter, its standout feature is automatic switching to bypass operation after start-up completion, reducing energy consumption and improving equipment stability.

This intelligent motor soft starter supports two start modes (voltage ramp start, current-limiting start) and two stop modes (free stop, timed soft stop). As a professional in-line soft starter, it is equipped with a complete protection system, including multiple safeguards such as input phase loss, output phase loss, overload, overcurrent, and underload. It supports RS485 communication (Modbus-RTU protocol) and Chinese/English display, adapting to 220V/380V voltage levels and star or internal delta connection methods to meet diverse industrial scenario requirements for soft starter applications.

Its core design focuses on high reliability, low energy consumption, and easy operation. Through optimized circuit layout and built-in bypass structure, this Bypass Soft Starter ensures long-term stable operation in harsh industrial environments, suitable for various small to medium-sized industrial equipment such as pumps, fans, and conveyors that require a reliable motor soft starter.

Applications

The ZHR10 Series Integrated Bypass Soft Starter is widely used in small-to-medium industrial scenarios, commercial facilities, and general machinery fields, providing smooth soft start solutions for low to medium-power equipment as a professional soft starter:

General Machinery & Light Industry Equipment

• Small machine tools, compressor drives powered by motor soft starter
• Packaging machinery, printing equipment matched with in-line soft starter
• Small conveyors, production lines equipped with Bypass Soft Starter
• Light industry processing auxiliary machinery supported by soft starter

Pumps & Water Treatment Equipment

• Civil/industrial sewage pumps, water supply pumps with dedicated motor soft starter
• Small booster pumps, circulation pumps powered by Integrated Bypass Soft Starter
• Water treatment metering pumps, chemical dosing pumps matched with soft starter
• Small irrigation pumps, drainage pumps supported by in-line soft starter

Fans & HVAC Systems

• Ventilation fans, exhaust fans equipped with motor soft starter
• Small central air conditioning fans powered by Bypass Soft Starter
• Industrial smoke exhaust fans, supply fans matched with Integrated Bypass Soft Starter
• HVAC system circulation fans supported by soft starter

Construction & Building Materials Field

• Small mixers, mortar mixers with motor soft starter
• Construction elevator auxiliary drives powered by in-line soft starter
• Small crushers, grinders matched with Bypass Soft Starter
• Building materials conveying equipment supported by soft starter

Agricultural & Livestock Equipment

• Small agricultural irrigation pumps equipped with motor soft starter
• Feed grinders, mixers powered by Integrated Bypass Soft Starter
• Livestock ventilation fans matched with soft starter
• Small grain processing machinery supported by in-line soft starter

Product Features

Built-in Bypass Design for Energy Efficiency (Integrated Bypass Soft Starter)

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

Dual Start Modes for Diverse Loads (Motor Soft Starter)

This soft starter supports voltage ramp start (smooth start to reduce impact) and current-limiting start (controls start-up current to protect the power grid), which can be flexibly selected according to load characteristics of equipment using in-line soft starter.

Comprehensive Protection System for Safety & Reliability (Bypass Soft Starter)

This Bypass Soft Starter integrates multiple protections including input phase loss, output phase loss, running overload, start-up overcurrent, running overcurrent, underload, thyristor breakdown, and three-phase imbalance to fully protect motors and equipment using motor soft starter.

Intelligent Communication & Remote Control (Soft Starter)

Equipped with an RS485 communication interface and supporting Modbus-RTU protocol, this motor soft starter enables remote control, centralized management, and data monitoring, reducing on-site operation difficulty for Integrated Bypass Soft Starter users.

Multi-Language Display for Easy Operation (Motor Soft Starter)

This soft starter supports Chinese/English bilingual operation interfaces, with clear LED status indicators and a detachable operation panel. Parameter setting is intuitive and fault troubleshooting is convenient for in-line soft starter applications.

Pump-Specific Functions for Scenario Optimization (Soft Starter)

This motor soft starter supports 4 pump-matching functions (float switch, electric contact pressure gauge, liquid level relay, etc.), optimizing start-stop logic for water supply/drainage scenarios and adapting to various pump equipment using Bypass Soft Starter.

Flexible Installation for Diverse Spaces (Integrated Bypass Soft Starter)

This Integrated Bypass Soft Starter features a wall-mounted installation design with a compact size, adapting to different on-site installation conditions. The power range covers 0.37~115KW, meeting the driving needs of small to medium-sized equipment requiring a soft starter.

Specifications

FAQ– BK-ZHR10 Integrated Bypass Soft Starter

Q1: What is an integrated bypass soft starter, and how is it different from a standard soft starter?
A: An integrated bypass soft starter—such as the BK-ZHR10 series—automatically switches to an internal bypass contactor after the motor starts smoothly, allowing current to flow directly through the bypass circuit instead of the thyristors. Unlike conventional soft starters that continuously run current through thyristors during operation, the integrated bypass design significantly reduces heat generation and energy loss, improves efficiency, and extends equipment life—especially in applications with frequent starts or continuous operation.

Q2: Why do soft starters need an integrated bypass function?
A: Thyristors generate heat and consume power when conducting current. By engaging an internal bypass once the motor reaches full speed, the system bypasses the thyristors entirely during normal operation. This delivers three key benefits: (1) lower energy consumption (typically 2–5% more efficient), (2) reduced thermal stress, and (3) higher long-term reliability. The BK-ZHR10 comes with the bypass contactor built-in—no external components needed—saving space, wiring, and cost.

Q3: Is the bypass switching in the BK-ZHR10 fully automatic? Does it require manual intervention?
A: Yes, it’s completely automatic. Once the motor completes its soft start phase (usually within seconds), the controller seamlessly engages the internal bypass contactor and disables the thyristor path. The transition is smooth, with no interruption to motor operation, and requires no user input or additional programming.

Q4: How much energy can I save by using a soft starter with integrated bypass?
A: In continuous-duty applications like pumps or fans, bypass operation eliminates thyristor conduction losses, leading to measurable energy savings. For example, a 55kW motor running 16 hours per day could save over 1,000 kWh annually compared to a non-bypass soft starter—translating to hundreds of dollars in reduced electricity costs per year, depending on local rates.

Q5: What are typical applications for integrated bypass soft starters like the BK-ZHR10?
A: The BK-ZHR10 series (0.37kW–115kW) is ideal for industrial and building automation systems that demand energy efficiency, reliability, and compact installation—including HVAC fans/pumps, air compressors, conveyor belts, mixers, and cooling towers—especially where frequent starting or long run times are required.

Q6: Does the bypass mode disable any protection features of the soft starter?
A: No. Even in bypass mode, the BK-ZHR10 continuously monitors critical parameters such as motor current, voltage, and temperature. If a fault occurs—such as overload, phase loss, or stall—the unit instantly disconnects the bypass and cuts power to protect the motor. All protective functions remain fully active during bypass operation.

Q7: Do I still need to install an external bypass contactor or thermal overload relay with the BK-ZHR10?
A: No. The BK-ZHR10 integrates the bypass contactor, control logic, and comprehensive motor protection into a single unit. It connects directly between the circuit breaker and motor, simplifying panel design. Many models also include built-in electronic overload protection, eliminating the need for separate thermal relays and further reducing component count and wiring complexity.