How do you size a soft starter?
How do you size a soft starter?
Soft starter sizing is determined by the horsepower or kW rating of the motor, coupled with the mains operating voltage. In an established installation that uses a NEMA-rated starter, a replacement soft starter may be selected based on the NEMA size of the starter.
Why do soft starters fail?
A combination of voltage spikes, too many starts per hour, or too much current during a start will destroy a soft starter. Phase imbalance for either voltage or current will cause an SCR to fail, as will a single phase condition on a 3-phase motor. What also needs to be considered is the load being started.
Do you need a contactor with a soft starter?
The purpose of the line contactor is to provide a means of removing AC line voltage from the softstart. Due to leakage currents through the solid state switches, hazardous voltages can be present on the load side of the softstarter when power is applied to the line side of the softstarter.
How do you troubleshoot a soft starter?
Restart the soft starter. To reset the soft starter, press [Reset] or activate the Reset remote input. If the soft starter has issued a warning, it resets itself when the cause of the warning has been resolved. Table 10.1 lists the protection mechanisms in the soft starter and the probable cause of the trip.
What causes SCR failure?
The cause for failure can be the result of violating the duty cycle limitations; i.e starting too often without proper elapsed time between starts. These transient surges can cause failure of the SCR’s as well. Lastly, a defective motor or an intermittently defective motor…
How do you test a SCR soft starter?
Disconnect the supply and the motor from the soft starter, Measure the resistance of the SCRs using a 500V insulation tester such as a megger. This can be done with the electronics connected, no damage will be caused by the 500V tester. Test from L1 to T1, L2 to T2 and L3 to T3.
Why we use bypass contactor in soft starter?
Soft starters protect AC electric motors at startup by reducing inrush currents and limiting torque. After the motor is up to speed, the soft starter transitions control over to a bypass contactor. The bypass contactor acts as “cruise control” because it allows the motor to continuously run at full speed.
What is bypass soft starter?
The bypass contactor is an internal or external bypassing device that allows a soft starter to run continuously after the start cycle is completed. The bypass contactor closes after the motor’s starting period is completed and opens after a stop or fault command is detected.
When checking a motor starter what can be checked if there is a suspected problem?
Check the motor starter leads for a phase-to-phase or a phase-to-ground short. If either of these two problems exists, check the motor lead wiring. If the motor starter leads are clear, move on to the motor. With the motor still disconnected, check the motor leads for a phase-to-phase or a phase-to-ground short.
Why choose csxi soft starter?
The CSXi soft starter’s small size and integrated bypass relays make installation easy, and allow the soft starter to fit in compact enclosures with limited ventilation. Rotary switches simplify configuration, and remote display and communication options allow trouble-free integration into common control networks. Read more…
What is a compact soft starter?
CSXi compact soft starters are a comprehensive motor starting and protection solution. These compact, reliable starters provide the latest constant current start technology and robust TVR soft stop, to reduce electrical and mechanical stress on your motor.
What is the AuCom emx3?
The EMX3 is a comprehensive motor management system for the most demanding soft starting and stopping applications. With an impressive range of features, including AuCom’s innovative XLR-8 technology, the EMX3 delivers superior performance and an unprecedented level of flexibility in a compact and user-friendly package.
What is the emx4i soft starter?
The EMX4i Soft Starter sets new standards for soft start technology. Not only is the EMX4i smaller, more powerful and packed with new control and protection features, it also introduces the game-changing Smart Card capability. Fitting a Smart Card to the EMX4i transforms it from super smart motor controller to complete system controller.
