V90 EPOS with SinaPos

Hi I don't find what are those parameters and their meaning;

Velocity 0[1000 LU/min] Velocity in [1000 LU/min] for MDI mode

OverV INT 100[%] Velocity override active for all modes: 0- 199%

OverAcc INT 100[%] Acceleration override active 0-100%

OverDec INT 100[%] Deceleration override active 0-100%

1st : What's a MDI mode? In my setup I have 10 LU = 1mm. The nominal speed shall be 3000 mm/s, so what value should I input for Velocity

2nd: What are those override values, how to interpret them. For velocity setpoint I give 30000 and for all override values were 100, then playing around I gave all override values to 1, which should mean 1%, but no big decrease in acceleration and speed can be observed, so what are these values for?

EDIT:

Could be a source of the problem wrong Velocity input: I gave 30000 (3000 mm/s @ 10 LU= 1mm), but it should be 30000*60/1000 = 1800 [1000 LU/min] ? Therefore any velocity override higher than 6% (30000*6/100=1800) is resulting an additional speed setpoint?

Hello,

MDI is let's say the "normal" positioning mode. For SINA_POS those are modes 1 and 2.

The velocity setpoint is given in the unit 1000LU/min -> attention: minute - not second. So for 3000mm/s you would have  1.800.000 LU/min -> so you need to enter 1 800 [1000LU/min]. Here you see also why it is in [1000LU/min], because of the large values that occur if you have a high resolution and high speeds.

The overrides are as you described. They need to have an effect in mode 1 and 2. For jogging for example the velocity has no influence, as the jogging velocity is another fixed parameter in the drive.

Also the acceleration / deceleration are fixed values in the drive. With the override you can vary them before executing a new positioning task! The override is multiplied with the fixed maximum value. The dynamic values are always taken over in the moment of the "execute" command. Changing them during motion does not have an influence.

Hi RB91,

That's exactly what I saw when reading multiple manuals of SinaPos and editing my question. On the field, without internet connection, I thought a velocity setpoint shall be in LU/s , but I was wrong, further it is very confusing, so particular care should be used to understand that speed setpoint is 1000 LU/min.

Thanks.

Hi,

the speed setpoint channel is not active when basic positioner is activated. The output speed of the position controller is bypassed the ramp function and going directly to the speed controller. This makes sense because the position controller is here the highest controller in the control cascade and so the setpoints for the position controller need to be ramped. And the setpoint generator for the position controller is the EPOS. So the dynamic values of the EPOS define the ramps.

You cannot really say that the default values are very high (I just know them for S120), because as they are in unit [LU/s²] it depends on the setting for "LU per load revolution" whether this value is high or not. For a low resolution the acceleration is quite high. For a high selected resolution the value could be quite low.

It would make sense to have different approach:

1. If EPOS is selected then the ramp generator could be made not available if it has no function in EPOS

2. Instead of having a second parameter set of EPOS acc, dec. The same ramp generator could be used instead

The EPOS itself has to output position interpolation point, so that follow the set acc,dec and max. speed. So in theory it doesn't have any different settings than ramp generator. But now, the question is : what profile shape is EPOS? Nowhere is documented, so it has to be trapezoidal. Therefore V90 EPOS has no s-shape (jerk limit) velocity profile.  

Dear Marko, 

Have you figured it out? How to set "S-curve" for jogging in EPOS mode in V90?

Best regards,

Lukas

Hi,

it is as I have written before: you can set the jerk values in p2574 and p2575. These values limit the rise of the acceleration / deceleration ramp.