ParaffinPower

File Name: Tracking product on conveyor File Submitter: ParaffinPower File Submitted: 12 Feb 2006 File Category: PLC Sample Code Products arrive on conveyor irregularly pitched. Conveyor is equipped with an encoder or maybe a proxy looking at the sprocket. This program captures the position and then multiple FB calls can be made to give an output at a distance from the input point maybe at a label inspction point or reject unit. The Shift register readout FB can be called as many times as necessary. The encoder can be connected to a high-speed counter meaning that the PLC scan need not 'see' every number i.e the encoder counter can be asynchronous. I've simulated this in this program by incrementing the 'encoder' with a timed interrupt. Adjacent to the product position stack is a product status stack so data can be written in at any point too e.g. I'm in front of the label detect sensor - if it's on then I can enter a '1' (say) into the stack. As the status is kept in a Word then upto 16 devices can write into the stack. Subsequent writes are ORed with existing data. This can be achieved with FIFO but this method is more efficient as data is not actually moved just pointers to the data. Click here to download this file

Hi folks Using an L7 inverter (well a few between 5.5 and 11Kw) with the PLC option board. I have an NT2S hmi connected. Here's the thing...when the inverter is stopped, comms is fine; when the inverter runs then comms is interrupted, indicated by '!!!' in the variable fields. When the inverter stops again, comms is restored. I guess it's noise related. The cable to the screen leaves the power wiring as soon as it can - i.e. straight out. One more thing. I'm using the transfer data option to read D1-01 to D1-07 (Memobus address 280-287) in one hit. I'd like to get to D1-08 to D1-17, but the memobus addresses are not sequential. Will I have to issue separate read commands, or will it compensate for the 'gaps'? Any thoughts? Thanks -Pp