Etel DSC Series User Manual

Operation & Software Manual
362
Direct Drives & Systems
Chapter E: Appendixes ETEL Doc. - Operation & Software Manual # DSC2P 903 / Ver. F / 3/6/05
There is a better resolution with the drive than the user. In the above example, the motor can reach a maximum
speed (SPD command) with a certain amount of user resolution, but the controller will calculate the speed
trajectory with a higher resolution.
20.2 Current, force and torque units
The current, force and torque are in increment too. The linear motors are expressed in force, and rotary motors
in torque. Both quantities are measured from the motor current.
The force F from a linear motor is expressed in Newton and is proportional to the current according to the
following formula:
with F = force [N]
K
t
= motor force constant [N/A]
I = current [A]
The torque T from a rotary motor is expressed in Newton meter and is proportional to the current according
to the following formula:
with T = torque [N · m]
K
t
= motor force constant [N · m/A]
I = current [A]
The constant K
t
is given for every motor (linear or rotary). The formulae which calculates the currents and
forces in ISO units from their increment values and vice-versa are given bellow.
For the next part of this chapter, the units will be abbreviated as follows. In all other cases, a formula will be
given.
Abbreviation used in the table below: I
max, controller
= [A] maximum current delivered by the drive = M82/100
K
t
= [N/A] Force constant for a linear motor.
K
t
= [N ⋅ m/A] Torque constant for a rotary motor.
Notation Signification Equivalent in ISO unit
Current [ci] Current increment [A]
Force [foi] Force increment (linear motors) [N]
Torque [toi] Torque increment (rotary motors) [N · m]
Unit Quantity Conversion formulae
Concerned
quantities
[ci]
Current
increment
[A] → [ci]
[ci] → [A]
• K83, K91,
K92, K44
• M20 to M24
[foi]
Force
increment
(linear motors)
[N] → [foi]
[foi] → [N]
•K60
• M30 to M32
Controller resolution [m/s]⇒
PCod
256 1024 2
K77
k⋅⋅⋅
------------------------------------------------
=
F [N] K
t
I⋅=
T [N m]⋅ K
t
I⋅=
Current [ci] Current [A]
32768
I
max, controller
------------------------------
⋅=
Current [A] Current [ci]
I
max, controller
32768
------------------------------
⋅=
Force [foi] Force [N]
32768
K
t
I
max, controller
⋅
-----------------------------------------
⋅=
Force [N] Force [foi]
K
t
I
max, controller
⋅
32768
-----------------------------------------
⋅=

Etel DSC Series Specifications

General

Brand	Etel
Model	DSC Series
Category	Controller
Language	English