Tasc drive problems

[b-spark]

Hi, its been a while since I've used this. I was hoping somebody could explain the principles of a tasc drive, I've never come across them before. Basically we have been ask to replace the main speed controller, and stop/start. I'm having problems integrating a bench built one. It consists of the same switching stop/start and a 1k pot. When it shuts down the clutch tasc drive is still running. Is this normal? Ie Estop activated. Once put back in the conveyer starts up instantly. Also the 1k pot has limited range, I've added two 1k resistors to either side of the wiper to give me smoother range. No change at all. Your advice would be great!!!

 

[SparkyChick]

Never used them, but the 1k pot... when you say it has a limited range, is it that all the adjustment appears to be at one end of the actuator travel? If so, could be you need to switch types.

Pots are usually available in linear and logarithmic where the adjustment across the travel follows a linear or logarithmic curve. So, for logarithmic, the adjustment can appear to be compressed at one end of the travel with very little change across the rest of the track.

 

[b-spark]

Could be just that you know,it is at one side either side if the wiper Fyi Its not a 1k pot but a 10k "misspelling" I've put the 1k resistors in an attempt to open the band, the original was a 1k, this still had no affect. nobody knows how it works we have only retrofitted the controls. Will try this thanks!!!!

 

[Andy-1960]

Blimey!! Been a while since I've seen one of these, if I remember rightly, these units control a coupling between the motor and the load. The motor runs at a constant speed and the controller adjusts the coupling to vary the speed of the load.. bit like a slipping clutch. I believe they needed a load on the output shaft to enable it to vary speed.

 

[davesparks]

When you say that the drive stays running when an E-stop is activated and once put back in that the conveyor starts again do you mean that when the E-stop button is released the conveyor starts without any further actions being needed?
If so then this surely does not comply with current law, and you are potentially in a lot of trouble.

 

[b-spark]

Thanks everyone, I've managed with abit more research to figure it out. I've removed the pots and put in resistors, this gives me a happy medium for speed for the line operatives.
"Davesparks" I'm aware thats mostly my concern, It did exactly that. I've since rewired the drive, to stop this, its really old stuff I'm 33 and haven't come across one yet, 16 years doing the job. My guess its never worked, as the night guys said it always hummed when the lines off.