vfd required extas


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vfd required extas

Post by johnscnc » Wed Mar 31, 2010 1:52 am

hi what "extas" are required for useing the automationdirect gs2 vfd ?
the braking resistor?
the line reactor?
the zero phase reactor?
the input fuse kits?
i'd like to know what is all needed so i can make one order and get it all the first time. thanks, John :mrgreen:

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Joined: Thu Mar 04, 2010 4:03 pm

Re: vfd required extas

Post by diycncscott » Wed Mar 31, 2010 10:09 am

Hi John,

Technically, you don't need any of the extras you have listed in order to run the GS2 inverter with our GP4IOD or DC3IOB MPU11 based kits.

That said, my personal opinions are:

Braking resistor(s) - Recommended: These allow the inverter to decelerate the spindle to a stop MUCH more rapidly than the internal circuitry of the inverter could otherwise provide. It depends on speed, size of spindle, gear range, tooling etc... but an inverter with braking resistors can generally stop the spindle in as little as a 1-2 seconds while an inverter without braking resistors may take 5-10 seconds.

Fusing of some type - Recommended: For obvious reasons

Line Reactor and Zero Phase Reactor I won't tell you not to use them but I will tell you that very few installations I know of have used them. Zero Phase reactors keep noise down between the inverter and the spindle motor and Line reactors are used to help keep the incoming power to the inverter clean. For most lower HP (<10HP) installations in areas with reasonable power, people seem to be able to get by with good wiring practice.

Thoughts to consider: How "clean" is my incoming power? How much does the line reactor cost? How much will it cost to replace my inverter?


From the automation direct site:

•Input line reactors protect the AC drive from transient overvoltage conditions, typically caused by utility capacitor switching. The input line reactor also reduces the harmonics associated with AC drives. Input line reactors are recommended for all installations.

•Output line reactors protect the motor insulation against AC drive short circuits and IGBT reflective wave damage, and also “smooth” the motor current waveform, allowing the motor to run cooler. They are recommended for operating “non-inverter-duty” motors and when the length of wiring between the AC drive and motor exceeds 75 feet.

•NOTE: If you purchase an AC line reactor with your AC drive order, you'll receive an extra year of warranty coverage in addition to the standard warranty period.

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