The first item to consider is the load, measured in amperes. This load amperage is the amount of current required to power your device at the line voltage. It is important to know this at the line voltage you intend to use because the current will change with the voltage according to P=IV (sometimes referred to as P=VA), where. Next, you should confirm the control voltage to power the contactor. This can be the same as the line voltage, however often a lower voltage is selected for the contactor for safety purposes. Generally, coil voltages are 250V or. IEC uses utilization categories, or “codes,” to describe the type of electrical load and duty cycle of the load(s) specifically. This is important because. Auxiliary contacts allow additional operations to take place when the contactor is energized. Multiple auxiliary contacts can be added in. Another consideration is whether the motor operation requires reversing of the direction, in which case a reversing contactor would be.
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What type of contactor is used for capacitor switching?
Contactors for Capacitor Switching(UA 16 to UA 110) Maximum permissible peak current Î< 100 times the nominal rms current of the switched capacitor. A... and AF... Standard Contactors(A 12 to A 300 and AF 50 to AF 750) Maximum permissible peak current Î < 30 times the nominal rms current of the switched capacitor. Contactors for Capacitor Switching
Which contactors are suited for capacitor bank switching?
Application The A...and AF...contactors are suited for capacitor bank switching for the peak current and power values in the table below. The capacitors must be discharged (maximum residual voltage at terminals < 50 V)before being re-energized when the contactors are making.
How to size a contactor?
There are 5 primary things to consider when determining how to size a contactor for your application: 1. Full Load Amperage at Line Voltage The first item to consider is the load, measured in amperes. This load amperage is the amount of current required to power your device at the line voltage.
If a motor will be jogged or have frequent stop/starts, then it should be accounted for by choosing a slightly larger contactor. It's not just a question of what type of device you are powering, but also how it may be used. Springer Controls sizes our contactors for 10 million operations to ensure long life.
A 30contactor (22 kvar, 380/400 V). This contactor accepts a maximum peak current of 1900 Â. Case no. 2 - Inrush peak current: 2500 Â Possibility no. 1as per table on page 5 UA 26contactor (20 kvar, 400 V). This contactor accepts a maximum peak current of 3000 Â (U e < 500V). Possibility no. 2as per table on page 4
What type of contactors can be used on multi-step capacitor bank?
The use of standard A 9 A 110 3-pole contactors is then possible on multi-step capacitor bank. The capacitors must be discharged (maximum residual voltage at terminals < 50 V)before being re-energized when the contactors are making. In these conditions, electrical durability of contactors is larger than 100 000 operating cycles. Selection Table