Product category:
Industrial Drives/Controls
News Release from: Invertek Drives | Subject: Optidrive
Edited by the Engineeringtalk Editorial
Team on 18 July 2003
Drives help feed hungry mouths
Variable speed control has revolutionised the preparation of animal feed at a cattle ranch in South Africa.
On the 22,000 acre Manjoh ranch near Johannesburg, South Africa, the Da Costa brothers fatten up to 10,000 beef cattle at a time Feeding that number of hungry cattle daily is a major exercise and on this scale, buying in preprepared feed is not an option, and so preparing the feed, mostly grown locally and on the ranch itself, is a big part of the task
This article was originally published on Engineeringtalk on 16 May 2000 at 8.00am (UK)
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New package offers complete remote drive control
Invertek Drives has announced a complete remote control and PC based drive programming and analysis package for its innovative range of Optidrive AC variable speed drives.
New package offers complete remote drive control
Invertek Drives have announced a complete remote control and PC based drive programming and analysis package for their innovative range of Optidrive AC variable speed drives.
The steers are fed on a rich mix of hay, wheat bran, maize silage and molasses.
All these ingredients have to be mixed, in 9t batches, in a feed mixer rather like a giant kitchen blender.
Previously, the mixer was mobile.
Further reading
Entry-level drive maintains standards
The new entry level Optidrive E provides a highly cost effective solution to a range of basic variable speed drive applications.
Drives keep their cool and save energy
Invertek Drives are proving to be very popular with Nuon, one of the main electricity suppliers in Holland and a major supplier of hot water to domestic central heating systems.
It was loaded at the feed mill, and towed by tractor to the feed-lot, with the mixer chopping blades driven from the drive take-off on the rear of the tractor.
The mixer would then be driven along the feed troughs, downloading as it went.
This process always left feed in the mixer after unloading because of the relatively slow speed of the blades so it was inefficient and time consuming and the da Costas sought to automate and speed up the process.
Invertek Optidrive variable speed control of motor driven static mixers proved to be the answer.
Manjoh's two feed mixers were fixed in place in the feed mill and are now driven by standard 400V, six-pole 90 and 55kW electric motors at up to 1800rev/min, taking advantage of the Optidrive's ability to drive the motors at beyond their nominal full speed when load torque demand has reduced.
The mixers are now top filled with the chosen mix of ingredients using motorised front loaders.
The loading and mixing cycle takes only 15min, with the blades being driven at 1000rev/min, by which time one of the tractor-driven hoppers has returned from the feed-lot and been positioned under the take off conveyor.
With the mixer still running, a door in the side is opened hydraulically and the chopped feed flows out onto the take-off conveyor and up into the mobile hopper.
Computer control via load sensor feedback monitors the weight of feed in the mixer.
When the load has dropped to 1000kg, at which point the torque requirement has reduced substantially, the drives are speeded up to 90Hz, 1800rev/min, using the centrifugal force to achieve efficient emptying of the mixer.
When the weight drops below 200kg, the drives are stopped.
Unloading takes no more than 5min; the tractor heads off back to the feed lot and the mixer is reloaded.
The cycle is run again and another tractor is waiting to receive 9t of mixed feed.
According to Johnny da Costa, "Electronic variable speed control means that the whole process is now much more cost effective, fuel bills are down, the feed mix is more consistent and the cycle time has been reduced to 20min, empty to empty, so that 20 mixing cycles can now easily be accommodated every day".
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