Combination Starters: A Quick Guide to How They Work

Quick Summary: A combination starter houses a motor starter, a disconnect switch and short-circuit protection in a single enclosure.

• It saves panel space and reduces wiring and installation time compared with separate enclosures.
• Its components are pre-engineered to work reliably together.
• A single interface makes lockout/tagout procedures more effective during maintenance.

What Is a Combination Starter?

A combination starter integrates a motor starter, a disconnect switch and protective components into one unit. It safely starts and stops an electric motor, protects it against electrical faults, and simplifies wiring and installation.

What is a motor starter? These electrical devices safely start and stop electric motors while providing protection against electrical faults. A combination motor starter takes this idea further, integrating multiple components into a single unit to streamline motor control. This typically includes a:

• Motor starter
• Disconnect switch
• Protective components

This combination system provides extra convenience and safety for operators and equipment. Having all of these in one unit simplifies wiring and reduces installation time. It also improves coordination between components.

How Does a Combination Motor Starter Work?

When the starter is activated, a contactor closes and current flows to the motor. At the same time, an overload relay checks that the motor's current draw stays within an acceptable range and shuts off power if it detects a dangerous overload.

Primarily, combination motor starters control the electrical power flow to motors along with several layers of protection. When the starter is activated, a contactor closes, which allows current to flow to the motor. At the same time, an overload relay checks to ensure that the motor's current draw is within an acceptable range, shutting off the power if dangerous overload conditions are detected.

The combination of a motor starter and a disconnect switch into one unit eliminates complexity.

What Are the Types of Combination Starters?

Combination starters come in four main types: manual, magnetic, soft start and reversing.

You'll find several types of motor controllers under the combination starter category:

• Manual motor controller units require an operator to physically start the motor. They're simple but cost-effective for smaller applications.
• Magnetic combination starters use electromagnetic components on the contactors so they can be activated remotely.
• Soft start combination starters are designed to reduce inrush current. They gradually ramp up the power flow for a smoother start.
• Reversing starters allow the motor to run in either direction.

Combination vs. Non-Combination Starters: What Is the Difference?

A traditional setup houses the disconnect switch, motor starter and protective devices in separate enclosures. A combination starter puts all of them in one unit, which reduces wiring complexity, installation time, labor costs and panel space.

The combination of components provides some major practical advantages over the traditional separate-component approach. With traditional motor starters, the disconnect switches, motor starters, and protective devices are all contained in separate enclosures. This increases wiring complexity, installation time, labor costs, and the required panel space.

Combination motor starters combine all of these elements into one unit. Beyond the obvious space and complexity gains, this also allows the components to work better together. The individual components are all pre-engineered to work reliably together. The fact that they come preconnected in a single housing also eliminates installation errors that could lead to undesired motor behavior.

When Should You Use a Combination Starter?

Use a combination starter when panel space is limited, when you want simpler installation and maintenance, or when you want a single interface that makes lockout/tagout procedures more effective.

The stakes are high in industrial facilities. Motor control solutions must minimize downtime and maintenance requirements as much as possible. Combination motor starters are excellent at this, providing comprehensive protection with simplified installation and maintenance.

Industrial environments must also frequently work in space-constrained areas. Combination starters are typically more space-efficient than traditional separate-component systems. Some options put extra focus on delivering a small footprint, making them ideal for areas with space limitations.

These systems also provide increased safety and reliability. Operators and maintenance personnel have a singular interface to work with, making training and operation simpler. The integration of the motor starter and disconnect switch also increases the effectiveness of lockout/tagout procedures.

Get the Right Combination Motor Starter Solution from Teal Electric Company

As a trusted Siemens motor control distributor, Teal Electric Company offers a wide selection of Siemens motor starters. In our inventory, you will find a large stock of Siemens SIRIUS products, including Siemens IEC motor starters (sizes S00 to S12), NEMA motor starters (sizes 00 to 8 up to 900 HP), and configurable combination motor starter solutions.

Our decades of experience with Siemens products give us the knowledge to help you select the right combination of motor controllers for your specific application requirements. To learn more about the products we carry, contact us today.

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