Parameter Tecnology Object PTO

Hi to all, i m trying to set all the parameter in the area Mechanic of the tecnology object PTO.

 field  Pulses per motor revolution: how to find the value of my motor?

on datasheet i have that step angle 1.8deg..other data are current torque ecc that i think no matter for find the value to insert.

load movement  per motor revolution: from the image (see in attached) it look like that i can set juste a value for a linear movement. in my case i have a rotation.  how to set this field?

thanks in advance

Daniele32

Hi to all, i m trying to set all the parameter in the area Mechanic of the tecnology object PTO.

 field  Pulses per motor revolution: how to find the value of my motor?

on datasheet i have that step angle 1.8deg..other data are current torque ecc that i think no matter for find the value to insert.

load movement  per motor revolution: from the image (see in attached) it look like that i can set juste a value for a linear movement. in my case i have a rotation.  how to set this field?

thanks in advance

Hello.

I am assuming you are using a stepping motor. A drive / amplifier should be connected between the PLC and the motor. The drive will have some multiplying specification which need to be taken in account.

An old half-step drive would have a x2 multiplier. That is 200 x 2 = 400 pulses for each motor rotation.

Do these notes already help you?

Daniele32

there are 8 kind of micro step that you can set by dipswitch from 200 until 25600

So there is your answer.

Calculate what maximum RPM (revolutions per minute) or linear speed do you want. Keep in mind that the PLC can deliver 100,000 pulses per second. From this math you will be able to see what pulse multiplier setting you should use.

The other side of the coin: The multiplier will also dictate what is the smallest accurate distance that can be commanded.

Does this help you?

honestly i don t know..but we can suppose for example 500rpm...so what i should to write in the 2 field of the tecnology object?

could you explian the operations? soeey but is my first time and i don t have pratice

Daniele32

but i think that change just the accuracy of movement

Please review my previous comment. It can have an influence on the maximum allowed speed that can be commanded.

Assume for the argument that the multiplier is 1,000,000 (pulse per one motor revolution). The maximum pulse rate is 100,000 pulse per second from the PLC.

motor speed = 1.0M / 0.1M = 10 revolutions / second -> 600 rpm.

The motor may be specified at being able to run 2000rpm. That means the PLC is limiting you at 600rpm but the capacity is 2000rpm.

BUT..
Your project might not need a fast speed. Stepper motors are giving out the best torque at a lower speed. Torque reduces very quickly to bad torque rates when the speed increases to maximum. Engineering design requires the torque-speed curves of the motor to calculate the best solutions.