Motor Starter Panel



Hong Kong Switchgear Limited is one of the manufacturers of low voltage Motor Control Panel in Hong Kong. The design of the Switchboard or Panel is in accordance to BS EN 60439 part 1.



"HKS" LV Motor Control Panel can be floor or wall mounted depending on actual site conditions, 380V 3 phase 4 wire 50Hz. It is commonly used for:

  • Air-conditioning circulation pumps
  • Fire services main, sprinkler, booster and jockey pumps
  • Fresh and flush water pumps
  • Processing plants for motor control, etc
Starting Methods
  • Direct On Line Starting
  • Star / Delta Starting
  • Auto Transformer Starting
  • Soft Starter Starting
  • Frequency Inverter Starting
Technical data
Rated voltage : 380V, 3 phase 4 wire 50 Hz
Protection class : IP31 for indoor to IP55 for outdoor
Ambient temperature : -10oC to +35oC
Maximum mounting altitude : up to 2000m above sea level
Standards : comply to BS EN 60439 part 1



Digital Soft Starters

Why Use RUDOLF Soft Starters?
Smooth acceleration and deceleration reduces the stress on motor and plant offering:
Lower plant maintenance costs
Less process waste
Minimised energy consumption

Also, in comparison to other types of motor starting:
Cost savings over inverters for fixed speed applications
Extended motor life from:
Reduced inrush current
Reduced mechanical stress
Improved power factor

Areas of application:
Forestry-Sawmilling, Pump, Marine, Pumps, Compressors, Fans, Process Control, Conveyors

RUDOLF™ IMS2 starters are user friendly. Simple applications can be commissioned with only one programming adjustment. The required adjustment sets the motor¡¦s Full Load Current rating. For advanced applications, the IMS2 provides an extensive range of functions that cover the majority of motor starting and control requirements.


RUDOLF™ MSX3 Series Soft Start Controllers provide sophisticated soft start control for new or existing motor installations. All three phases are controlled by the MSX3. This provides users with the full range of electrical and mechanical benefits available from soft start technology.

MSX3 Series Soft Start Controllers are simple to install and easy to use. In new installations the MSX3 is easily integrated with a motor overload device and any other control equipment required by the installer to form a complete motor starting panel.

ZSA (3~25A, 100~600V)
RUDOLF ZSA are compact low cost soft starters for small three-phase motors from 1.1kW up to 11kW respectively. They overcome the disadvantage of the usual DOL (direct-on-line) starter and star-delta starters.

RUDOLF incorporates a microcontroller and semiconductor switching devices to control the voltage to the motor, gradually increasing to a maximum. Starting current and torque are correspondingly reduced, and the acceleration time extended.
IMS Series (25-372A, 200~600V)
IMS Series: An integrated approach to soft start & motor protection system for motors up to 200kW. Available in both IP32 and IP00 formats, the IMS has a built-in push button control panel and it can be mounted directly on a wall or fitted within a switchboard enclosure.
MSX2 Series (25~372A, 200~600V)
MSX2 Series: An advanced compact soft start controller designed for inclusion within motor control centres. Suitable for motors up to 200kW, the MSX2 starters are easily incorporated into any control circuit and are suitable for use with any type of motor protection device.
EMX2 Series (222-1393A, 200~600V)
EMX2 Series: A comprehensive motor management system providing the latest in soft start control, advanced motor/load protection systems and extensive control & interface features, all in a single integrated package. Suitable for motors up to 800kW.


Variable Speed Drive

RUDOLF employs some of the most advanced technology seen in variable speed drives today. Manufactured specifically for motor and control solutions, RUDOLF boasts many features to benefit your application.

Couple this with its reliability and efficiency, RUDOLF becomes a popular choice for complete fan and pump control.



This solid and user-friendly inverter covers motor capacities from 0.75kW ~ 800kW (with larger capacities to follow) and voltage levels from 200 to 690V with IP00-IP54.

One of our biggest advantage is our versatile Rudolf programmes, which allows customers to use the same drive for the simplest application, such as pumps, to more complex applications like cranes.

The latest additions to the Rudolf product programme are the CX, CXS, CXL boasting some of the highest power / volume ratios in the market.

EU Directives have been observed in the design of the CX/CXL/CXS Series and with this in mind each drive is CE marked.

Good electromagnetic immunity and low level emissions have been accomplished by using a steel enclosure built-in supply line Harmonic filter (AC-line choke), DC-link filter and RFI/EMC Filters. Rudolf AC Inverter effectively reduces harmonic and protection against power torque.

All of the units meet the latest CE-standards and comply with the strict EMC regulations EN50081-1, -2, EN50082-1, -2 and IEEE519. Excellent dynamic motor control is produced, using state of the art Open Loop Vector Control, a fast ASIC circuit and current measurement in all three output phases. A versatile PLC-like block-programming system can provide very specialised "1 off" applications.

Thanks to its uncomplicated interface and parameter menu structure, the CX/CXL/CXS Series have proven to be suitable for both the most demanding applications and simple applications alike.

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