ultra 3000i/Ultraware

Hi All,

I having some problems setting up a new drive using Ultraware.

The application is a simple bucket conveyor that indexes along each time a product falls into a bucket. The product is detected by a PE Sensor, which gives the Index start signal.

The Stop position of the drive is detected by a stop proximity switch. There is a toothed wheel that rotates such that the (rotational) distance between each tooth is equal to the length of the bucket.

I have had this working fine at low speed - the PE sensor detects product, the motor starts & stops Ok when the stop proximity is triggered.

The problem I have relates to the speed that this must all happen at - the product runs at a rate of 8000 units per hour ( or about 2.2 units per second).

How it is is happening at the moment is that the drive starts-->runs-->stops, and then can only re-start once it has been stopped

What I am trying to achieve is that if the start signal is triggered once the motor is in motion, the motor needs to continue to run until the next bucket is reached.

I have configured the drive to run in indexing mode, and I am only using Index 0 at the moment. The mode of Index 0 is "registration". The PE Sensor is configured as "Start Indexing", the stop proximity is configured as "Registration Sensor"

Any suggestions on how this could be achieved?

Thanks

I don't believe the Ultra 3000 has the capability to do what you need--what's often called blended motion.

One possible way to handle this would be with the Registration input on the drive. If I understand correctly, right now you're feeding the sensor directly into this input, causing the motor to stop when it's activated (possibly after some registration distance). If you have a PLC with I/O available, you could wire the sensor to the PLC and a PLC output to the registration input. The logic would be set up so that the registration signal would only be activated if the start signal is not received by some particular time. (So I guess you'd have to run the start signal through the PLC too.) The Index 0 move distance would need to be the length of multiple buckets--the distance it will move if the registration input is not detected.

Another option would be to forget the registration move and just use the jog functions of the drive. You'd still need a PLC to read the two sensors, but Index 0 would be set up as Jogging. So, it would run when the Start Indexing input (connected to a PLC output) is true and stop when it's false. Here you would be doing all of the logic in the PLC. I think this might be a simpler solution than my first suggestion.

Thanks John,

I thought that might be the case --> that I might have to do a few changes in the PLC.

The PLC is a SLC 5/05. I was worried about whether running through the PLC may slow everything down a bit, but its scan time is less than 10msec (its not doing much work).

The only reason that I am changing out the drive is that the old drive is a SEW unit that runs on some DOS software that no-one seems to have a copy of the program - and it runs quite fine..