SEW-Eurodrive IPOS plus - 7 Position Detection Via Binary Inputs; Types of Built-In Encoders; Principle of the Position Detection

96
Manual – IPOSplus®
7
Types of built-in encoders
Position Detection via Binary Inputs
7 Position Detection via Binary Inputs
7.1 Types of built-in encoders
For asynchronous AC motors, SEW-EURODRIVE offers a position detection with a sim-
ple incremental encoder (without position control). Those are built-in encoders.
The following table illustrates recommended encoders for the respective products:
• You may also use a different encoder, but observe the following information:
7.2 Principle of the position detection
The track signals are transmitted to 2 binary inputs of your inverter and evaluated with-
out encoder option. Index 8845 was implemented in order to activate the "Position de-
tection".
Index 8845 has the following assignment:
• Position detection deactivated: 8845 = "0"
• Position detection activated: 8845 = "1"
You can set index 8845 in an IPOS
plus®
program with the MOVILINK command.
The following table illustrates the processing of the actual position in the IPOS
plus®
pro-
gram:
Encoder Unit
MOVIDRIVE
®
B MOVITRAC
®
B MQx module
EI7C X
EI76 X X
EI72
EI71
ES16 X
NV26 (proximity sensor) X
INFORMATION
If the resolution is too high, the encoder might not be evaluated correctly at nominal
speed.
• Select an encoder with a resolution that suits the pulse frequency of the inverter.
• Observe the technical data of the built-in encoders in "Drive Engineering, Practical
Implementation – Encoder systems" and the technical data of the binary inputs
(counter input).
Processing of the actual position in the IPOS
plus®
program
2211727115
• The actual position of the built-in encoder is mapped
automatically in the IPOS
plus®
variable H511 and can be
processed using program control.
• The built-in encoder can be used in particular for applications
in which positioning usually takes place using rapid speed/
creep speed by means of several proximity switches.
• The encoder cannot be used for motor control (operating
mode "…&n-control").
• The encoder cannot be used for direct position control
(operating mode "…& IPOS").
• The "Simple Positioning" application module in MOVITOOLS
®
MotionStudio can be used for simple positioning tasks with
MOVITRAC
®
B.
SV = System variable
IPOS = IPOS
plus®
program
M
IPOS
SV
O
P
i
f
kVA
Hz
n
P
i
f
kVA
Hz
n