AC Crane Control
Can I use Adjustable Frequency Drives with wound rotor motors?
Yes, provided that output load filters are provided. For more information, about these applications please contact EC&M.
What makes the ENDEAVOR® Crane Control Frequency drive different from an off-the-shelf HVAC drive?
The hardware and software of the Endeavor® frequency drive sub-unit has been modified to make an effective and safe crane drive system. It has been pre-programmed and designed specifically for crane use. HVAC drive units are specifically NOT to be used on crane systems without a thorough design review and the required modifications for crane applications. To apply a standard off-the-shelf HVAC frequency drive to a crane is considered to be unsafe, and is to be avoided.
Can I drive more than one bridge motor from the same drive and will the speed regulation be close enough for the bridge not to skew as it travels down the rails?
This can be done, but the answer depend on the control style, and the mechanics of the crane. Leaving mechanics aside, On AC contactor systems, motors are placed in parallel, and the mechanics of the crane must keep the crane from skewing. On AC variable frequency drive systems, if the mechanics alone are not sufficient to keep the crane from skewing, separate drives may be needed for each motor.
Is there a modern day replacement for CORPAK?
The original Class 6401 CORPAK control was AC Magnetic Amplifier control for infinitely variable speed hoist and travel controls. This was replaced in the mid-1960s by the Class 6401 STATA, primary thyristor (SCR) control. The STATA was in turn obsoleted in the mid-1980s. Modern replacement would include either AC Contactor controls (Ref Class 6400 catalog) , or the Class 6417 and 6418 Endeavor® Variable Frequency Control.
Will EC&M controls work with an existing Eddy Current Brake?
Yes, All we need is the ECB nameplate data to engineer a complete system around your ECB.
What do I do if I need an AC mill duty contactor with an AC operating coil?
We offer a small rectifier block, approximately 1" cube in size, with a protecting MOV, to be mounted at the DC terminals, which can provide DC power for several contactors. Please reference our Class 7004 or Class 8503 catalogs, pages 111 or 133, for basic schematic and part number details.