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5
Motor control (MCTRL)
5.11
Encoder/feedback system
276
Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23
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5.11
Encoder/feedback system
For the motor controls with speed monitoring the feedback signal can be supplied via an HTL
encoder at the digital input terminals (DI1/DI2 or DI6/DI7).
Danger!
• To avoid interference injections when an encoder is used, only use shielded motor and
encoder cables.
• If an HTL encoder is used at the digital input terminals:
Observe the maximum input frequencies of the digital inputs!
• DI1/DI2: f
max
= 100 kHz (
from version 11.00.00:
f
max
= 200 kHz)
• DI6/DI7: f
max
= 10 kHz
• Generally, we recommend the use of encoder signals with increments
≥
4
• With increments < 4, the evaluation may cause implausible values or a number
range overflow may occur when further processing the value.
• Increments > 2 are at least required for encoder signals that are exclusively
processed in the FB interconnection.
Note!
In the Lenze setting (e.g. when the device is delivered), the open-circuit monitoring of the
encoder is activated.
Encoder open-circuit monitoring
Note!
The encoder position can be saved safe against mains failure in the inverter.
• For this purpose, bit 0 must be set in
. The actual position of the motor control
is then saved in the inverter (not in the memory module) and thus remains known to
the drive control after mains switching.
Option "Actual MCTRL position received at mains switch-off"
• In case of a device replacement, this information gets lost and the home position
might be approached or set again once. A device replacement can be recognised by
using the SB
and a suitable function block interconnection.
Wiring diagram, assignment and electrical data of the digital input terminals can be
found in the
hardware manual 8400
in the chapter "technical data". The hardware
manual is stored in electronic form on the data carrier supplied with the 8400 inverter.