Festo Электромотор MTR-DCI - Manual (Page 214)

A. Technical appendix
A-14
Festo P.BE-MTR-DCI-CO-EN en 1209a
A.4 Conversion of the measuring units
A measuring system must be defined for specifying the para-
meters of the electric axis. In order to enable simple parame-
trizing for different application cases, the controller can be
set via the control panel or FCT so that the user can specify
or read all variables directly in the desired units on the power
take-off, e. g.:
– The metric measuring system for linear movements
(mm, mm/s, mm/s
2
)
– The angle measuring system for purely rotational move-
ments (degree, degree/s, degree/s
2
) or (rev, rev/s,
rev/s
2
)
– The imperial measuring system (inch, inch/s, inch/s
2
)
Each physical variable (position, speed and acceleration)
is adapted to the relevant measuring system by means of a
conversion factor.
In the controller all parameters are always saved in increment
specifications (inc, inc/s, inc/s
2
) and not converted until they are
written or read. For the display, conversion from the internal basis
system into the (pre)set measuring system takes place within the
firmware; for representation on the PC monitor within the FCT
software. In this way, the user does not need to carry out conver-
sion when entering values or when reading on the control panel
or in the FCT.
The direct transfer of values via the serial interface with CI com-
mands always takes place in the basis system and it is assumed
that conversion into increments has already taken place.
Conversion is carried out via the parameters:
– Feed constant (depending on the drive type)
– Gear reduction
– Encoder resolution = physical measuring steps per motor
revolution. With MTR-DCI: pulse quadruplication by digital
interpolation