In an industrial environment, or really any setting in which pains should be taken to protect expensive equipment, a soft starter is an excellent choice.
Let’s face it: With the amount of capital invested in the type of machinery that yields profit, protecting the investment also means avoiding downtime caused by machine damage.
Aptly named, the soft starter ensures that the motor undergoes a gradual start by slowly ramping up initial voltage. Also dubbed reduced-voltage soft starters, or RVSSs, these devices essentially protect AC electric motors from harm brought on by the sudden influx of power. Gently building to full speed, the soft starter is, as you have probably guessed, used only at start-up.
Voltage is reduced by the vast majority of soft starters with the use of a series of thyristors, or silicon controlled rectifiers, or SCRs. When SCRs are engaged in the “on” position, they allow current to flow. Likewise, in the “off” position, they restrict current.
During the ramp-up stage initiated by a soft starter,the rectifiers are engaged, but bypass contactors are deployed, as well. These contactors, which help to mitigate the chances of overheating, are disengaged after the motor is up to full speed.
The job of the electrical soft starter is to decreases current or voltage by created a temporary reduction in torque. Some soft starters employ solid-state components to aid in controlling the flow of the current, and are able to control up to three phases.
When It’s Important to Use a Soft Starter
In deciding when it’s best to take advantage of a soft starter, there are a few benefits to keep in mind.
You’ll definitely enjoy the benefit of the soft start in any application for which speed and torque control are a necessity only during start-up. A soft starter will also mitigate potential problems in any application for which the reduction of sizeable influxes of current at start up is a requirement.
The benefits of soft starts are not reserved solely for electrical systems, however. Soft starters can be of major benefit for applications that require a gentler start to alleviate torque spikes and tension often caused by an unregulated start. The quality, performance and safety of conveyors, belt-driven systems and gears can all be protected with the use of a soft starter.
Likewise, these starters are also ideal for situations in which pumps are utilized to decrease or eliminate surges of pressure derived from the rapid change of fluid directional flow within piping systems.
Available in a wide range of sizes, soft starters are easy to configure and are worth the effort of protecting an investment in the way of expensive machinery.
