In order to operate a "unknown" motor with encoder system, it is necessary to carry
out an adjustment in order to detect the system position.
This parameter is described in chapter 6.2.3.5 System offset.
6.1.6.8 Incremental encoder emulation
An incremental encoder emulation can be activated for channel B if the encoder
type for channel B ec16 is set to 16 "TTL output".
In this case, a position difference, which occurs at channel A from one control grid
cycle to the next, is converted into two rectangular incremental signals which are
shifted by 90° and output at channel B during the following control cycle. Due to
this non-continuous output, the position may fluctuate more than the reference po-
sition of channel A, especially at low speeds and with few signal periods.
How many signal periods per revolution shall be output is set in ec29 "signal peri-
ods per revolution B" in encoder parameter B group. The maximum is 16384.
If the position of channel A has the value zero within one revolution, a zero signal
is additionally output at channel B.
It is irrelevant which encoder type is evaluated at channel A. Also positions of the
resolver are converted into incremental signals.
Signals are only output if the position value on channel A is also valid, which is dis-
played in ec00. If channel A changes directly to error after switching on, e.g. be-
cause no encoder is connected, ec00 remains at 5 "enc. initialisation". If channel A
has a valid position after switching on and later changes to error, the encoder emu-
lation also changes to error.
An error is triggered if the maximum possible signal frequency of 500 kHz is ex-
ceeded.
Operation of absolute linear encoders
With these encoder types in ec16, linear motors can be operated current and
speed-controlled (provided the connected encoder is supported):
EnDat + 1Vpp, EnDat digital, Hiperface, BiSS Linear
With these encoder types, linear encoders can only be evaluated as position feed-
back:
SSI, TTL zero sig, Sin/Cos abs zero sig,
With these encoder types, linear motors can be operated current and speed-con-
trolled if the system position is measured each time after switching on. Otherwise
they can only be evaluated as position feedback:
Linear Sin/Cos with perodic zero sig, Linear Sin/Cos with distance-coded zero sig,
Linear TTL with perodic zero sig, Linear TTL with distance-coded zero sig,
All other encoder types in ec16 cannot be used for linear encoders.
As far as possible, the setting and use of linear encoders is kept the same as that
of rotary encoders. The few differences are described for the relevant parameters.
This means, for example, zero setting of the position in the encoder with ec36 or
saving and reading of motor data with ec46 in the encoder will work in the same
way if the encoder supports them.
To Next Page
Loading...
Need help?
General
