Bar code scanner with ML 1500

[advmin]

Hello Guys,
I am a beginner in PLC programming.

I am trying to add a Zebra DS457 FIXED MOUNT IMAGER with MICROLOGIX 1500 LRP to successfully select a particular program for a particular-sized tray

There are different trays of various sizes coming through the conveyor. The filling should be done inside the tray differently according to the size.
So the plc program would be different for different sizes.

My plan is to put a unique barcode for a particular size, so that when the imager reads a particular bar code ( say bar code for a 90mm tray ) the program to fill the 90mm tray should start.

1. How to connect the imager with the ML1500 since it only had rs 232 port (no ethernet)
2. How the output from the imager can energize an input in PLC so that a particular program selection is possible?
3. Is there any other suggestion for this process?

Please help me with your opinions and views


cheers.

 

[parky]

I cannot comment on the communications it will depend on what the scanner can output, the selection of a program is the easy bit (dependant on how you write your program or modify an existing one.
A simplistic way is to have recipes in the PLC so when a barcode is read, the barcode selects the parameters & puts those into the running recipe for example it may be that these are position, rotation, wrap cycle or what ever, it will depend on the actual barcode information comming in, without knowing this it is impossible to show you how to control the machine actions.
Some examples:
Bar code contains the pack size & probably other data that is not required.
Extract the pack size use that to set say for example from a position for that size.
if the different pack sizes use set programs i.e. you have seperate programs for each pack size then just with simple compare of the barcode with a list of stored codes select a program.
Have done many like this from simple box selection for diverting to packing stations i.e. each packing station was designated a number, the barcode was just a simple number system from 000 to 999, the barcode was read, the box tracked down a conveyor & diverted to the correct packing station.
Another would extract the product type use this code to itterate through stored recipes & load servo positions & other operations into a program & used the data to handle the strapping of the component.
Perhaps more detail on the structure of the barcode & what operations the PLC would do i.e. is it just a program that uses values for position etc. or are there seperate programs selected dependant on the type of product.

 

[JordanCClark]

For connectivity, use these:

https://www.rtautomation.com/product/435nbx/

 

[BachPhi]

435nbx is a good option for an obsolete plc.

 

[advmin]

Thank you Parky for the reply with a good example.
I will follow the instructions you shared through the example. Will update you soon on the progress

435nbx is a good option for an obsolete plc.

The issue is ML1500 does not support ethernet connectivity, so I am afraid that the only pathway is through RS 232. But when I tried connecting the imager with the PLC through the Rs 232 port ( using normal RS 232 cable), it was not even getting powered up. Is there any special Rs 232 pinout needed for this purpose?


cheers all

 

[joseph_e2]

... But when I tried connecting the imager with the PLC through the Rs 232 port ( using normal RS 232 cable), it was not even getting powered up. Is there any special Rs 232 pinout needed for this purpose?


cheers all

In my experience, devices generally don't get powered up via RS232 connections. I would be shocked (hehe) to find that the ML1500 provides any power at all on its serial port...

...though, now that I think about it, it may if it's configured for DH485.

Anyway...

Do you have a wiring diagram for your scanner? If it's powered via the same cable, you'll likely need to use some sort of breakout board in between to inject power. Maybe something like this:
https://www.digikey.com/en/products/detail/schmalztech-llc/ST-DB9-M-R-DIN/16000113

 

[advmin]

Thank you for your reply.
I will try once more by configuring channel 1 for DH 485 and will update you soon.


cheers

 

[joseph_e2]

DH485 will only work if the scanner supports it. It's different hardware and protocol.