1756-hyd02

Gents,

I have a project with three of these cards and I have a question. I have two axis of motion that are different because I need to do the following: I need to issue a MAM to send to a position to start, then after that, I need to disregard the position and follow a profile.. Basically, I need to just follow a profile that I have established. I would like for it to just send a voltage profile to the servo valve based on what I do with it.. I thought about using a MAJ with MCD. Also, I thought about using MDO but it has a .5 sec update time and I need it to be faster.. When using the MAJ, I did get some axis faults (position error) because we were testing without moving the wand.. Does anyone have any good way to do this.. I thought about using a cam profile or something but I wasn't sure how to do that.. Any assistance would be appreciated...

Thanks

Let´s wait for Peter natchwey he was the one who designed those boards, but cam profile is my preferred.

Actually, I can't help much

The HYD02 gets its positions from the PLC. The HYD02 only moves from point to point.

plcengineer said:

Gents,

I have a project with three of these cards and I have a question. I have two axis of motion that are different because I need to do the following: I need to issue a MAM to send to a position to start, then after that, I need to disregard the position and follow a profile.. Basically, I need to just follow a profile that I have established. I would like for it to just send a voltage profile to the servo valve based on what I do with it.. I thought about using a MAJ with MCD. Also, I thought about using MDO but it has a .5 sec update time and I need it to be faster.. When using the MAJ, I did get some axis faults (position error) because we were testing without moving the wand.. Does anyone have any good way to do this.. I thought about using a cam profile or something but I wasn't sure how to do that.. Any assistance would be appreciated...

Thanks

Click to expand...

What type of profile? Position or pressure?
Do you have feedback?
Do you care if it follows the profile with an error?


I thought that the Hyd card always required working position feedback?


A$$uming position feedback

Method A
1) MAM the Hyd axis to the start position
2) Use a MATC (Motion Axis Time CAM) on the hyd axis

Method B
1) Create a virtual axis Master
2) MAPC to the Hyd Axis to the Master Axis
3) MAM the Hyd axis to the start position
4) perform a MAM on the Virtual axis causing the Hyd axis to perform the CAM profile

Please tell us which version of Logix 5000 you are using

Michael

Here is what we have... The first item that we have to deal with is an intensifier. It has a servo valve -+10VDC with an LVDT feedback all going to the 1756-hyd02. When starting the press, we have to give an MAM to the intensifier to make it go to the starting position of 50% or wherever they need it.. Once the press starts, we need the intensifier servo output to follow an profile that we have already constructed. We constructed the profile by data logging the servo valve while the press was running. For example, if we are starting the intensifier position at 6".. Then, when the press starts, I sent a MAM to 18" and tried to use an MCD.. I thought that this would work but when we were monitoring the servooutputlevel tag, I never saw the 10v signal change until it got close to 18". It was like the 10 vdc signal was position based not speed.. Now, we are simulating this on the bench so I tried moving the wand by hand...

The next axis we have to deal with is the bucking cylinder.. With this guy, we have just a proportional valve 0-10vdc and a LVDT for feedback.. Basically, I need this to follow a profile as well but there will not be much movement on the wand because it basically holds pressure. For example, I need it to be at zero when the press starts, then we need it to send a profile output to the valve.. In regards to our data logging, we seen the press go 0, 50%, 50%, 50%,0 which equates to 0, 5v, 5v, 5v, 0.. These are all just steps in a profile that we have...

Any help would be appreciated.. we are using v19 logix 5K

Sounds like you are reverse engineering something that has become obsolete
A hydraulic diagram could be useful
I think the intensifier profile is probably running a pressure profile.

plcengineer said:

Also, I thought about using MDO but it has a .5 sec update time and I need it to be faster.

Click to expand...

This is ONLY the Enable Time (the Digital enable output) - Once Enabled the MDO will change the analog voltage at a combination of scan time and motion group update time - typically less than 10ms
Note MDO and MSO are mutually exclusive so before performing a MSO you must perform a MSF

Try the MDO
Also you may want to set the MDO ramp rate