AB 1746-HSTP1 module help

[Davek0974]

I'm getting back into the driving seat of plc programming after a long break, I have a machine rebuild and want to re-use an AB SLC 503 plc as I have it lying around along with a stack of I/O boards.

The only part I am unfamiliar with is the stepper control unit - 1746-HSTP1, this machine needs to talk to a ServoStar601 drive using step/direction signals to command a feed to supply X MM of material on each cycle.

Does anyone here have any examples of using this module that could offer advice?

 

[widelto]

dave:

if your SLC is dead you can use micrologix and use the same software with minor modifications, for stepper you can try AMCI modules:
http://www.amci.com/

 

[Davek0974]

I'm hoping she's alive still, but thanks for the tip.

 

[danatomega]

There are some programming example rungs in the document:
http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1746-um121_-en-p.pdf

 

[Davek0974]

Thanks, I have that but they have been described by others as weak and for a new user to this unit I was hoping for some detail etc. or more examples.

 

[Davek0974]

Ok, been studying the PDF linked above, have extracted some understanding of the data table contents (p6-1) and how it's transferred when needed but need help on one point...

I need to set it for step/direction so need to set output word 0, bit 10 to logic 1 (p4-2)

I presume this would be done in the configure step, but I can't figure out line 1 - N29:0 on p6-1. I see the first three entries are -32751, 17, 1 could someone explain possibly?

Much appreciated

 

[Davek0974]

Anyone?

I have the cpu up and running now so just need to figure this bit out.

 

[danatomega]

It looks as though configuration word 0 has bits 0, 4, and 15 set and according to the manual page 5-10 it's being set for absolute move and immediate stop - of course bit 15 says it's configuration mode (not command mode).

Page 6-2 has partial description in the rung comment - doesn't explain why word 1 (reserved) is set to anything or why word 2 has data as well.

 

[osmanmom]

do you want apply 1746-HSTP1 on servo star 601 ?

 

[Davek0974]

Thanks, following your reply, studying some more I see that

Word 0 has a value of -32751 which is -32768 (bit15) + 1 (bit0) + 16 (bit4)

Word 1 has a value of 17 which is 1 (bit0) + 16 (bit4)

Word 2 has a value of 1 which is (bit0)

In the back of the manual it shows for config word 0, bit0 is CW limit switch, bit4 is home limit switch and bit15 is config mode.
For config word 1, bit0 is the active level of the CW limit switch, bit4 is the active level of the home limit switch.
For config word 2, bit0 is is starting speed MSW.

That sort of explains the data in the N29:0 line of code (-32751, 17, 1)

What I am looking for is to set the board as step/direction control, and then I simply need three commands - jog fwd, jog Rev and move a set amount. There are no home switches in this application, it simply feeds material using relative moves, no need to home, ever.

The test rungs in the book are great but it's the config I can't grasp, do I need to config every move or only on startup? The book states the drive will fault until it has a happy config setup but I can't bench test this one so need to be nearly right from the start.

I will also need to get the "move finished" flag back into my program. There are no encoders etc.

Any more detail you can offer?

 

[Davek0974]

do you want apply 1746-HSTP1 on servo star 601 ?

Yes, the servostar has a step/direction input and the stepper has this output so it seemed logical.

This is a simple application, no feedback via encoders etc, just issue the step pulses and let the drive do the rest.

 

[osmanmom]

are running servo motor or stepper motor ?

 

[Davek0974]

According to the book, a config that does not have ability to home the module will not be accepted but if I can't use home switches, I will need to work round this, any ideas here too?

 

[Davek0974]

are running servo motor or stepper motor ?

It is connected to a servo motor and resolver.

 

[osmanmom]

you not answer my question whether using servo motor or stepper motor