Encoder Inputs; Specification Of The 11-Μa Pp Interface - HEIDENHAIN IK 220 Benutzerhandbuch

Encoder inputs

Specification of the 11-µA
The IK 220 supports encoders with the following interfaces:
• 11 µA
PP
• 1 V
PP
• EnDat 2.1
• SSI
The power supply for the encoders (typ. 5.12 V) is generated
from the +12 V of the PCI bus. Max. 800 mA of the +5 V power
supply for the encoders may be used for both axes.
The additional current taken from the +12 V of the PCI bus is:
I = I * 5.12 V * 1.35 / 12 V
(12V) (5V)
Example: I = 0.8 A * 5.12 V * 1.35 / 12 V = 461 mA
(5 V)
It must be ensured that the power supply limits for the encoder
are not exceeded. A voltage converter (370 225-xx) can be used
for large cable lengths. The voltage converter has an efficiency
of approx. 72 %, meaning that the permissible current con-
sumption of both axes is reduced to 0.72 * 800 mA = 576 mA.
interface
PP
Signal amplitudes
I , I (0°, 90°)
1 2
I (reference mark )
0
Signal levels for error
message
Maximum input frequency
Cable length
7 µA to 16 µA
PP PP
3.5 µA to 8 µA
≤ 2.5 µA
PP
Standard: 33 kHz,
switchable to 175 kHz
Max. 60 m
Hardware
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