IF10
A, B and 0 can be also independent single signals, e.g. from proximities,
photocells, etc. Since the level of every channel is selected individually (see the
DIL switch settings on page 26), it is possible to use different levels on the
inputs. Consequently it is possible, for instance, to get the position information
from the A, /A, B and /B channels of a RS-422 encoder, but to add the
corresponding 0 index pulse as an HTL signal from a remote photocell.
With HTL signals, the switching threshold is between 6.5V and 8V. The input uses
an internal pull-down resistor of 5kOhms.
Each of the two input terminals provides two auxiliary voltage outputs for easy
encoder supply: +5.2V / 125 mA and +24V* / 125 mA.
*) Output = power supply voltage – 2V
5.4 Asymmetric TTL Inputs
Only when exceptionally asymmetric TTL input signals must be processed (i.e. TTL
signals without inverted signal), a 2-position DIL switch located behind the front
plate must be set. This hidden switch becomes accessible by slightly lifting up
the front foil in the bottom (e.g. by means of a small screwdriver).
Switch position 1 affects all channels
of Input 1
Switch position 2 affects all channels
of Input 2
OFF
= Asymmetric operation with HTL
level (10 – 30V)
ON
= Asymmetric operation with TTL
level
For all general applications please do not touch the DIL switch hidden
under the front plate !
WARNING
Asymmetric TTL levels are most sensitive to noise and interference, therefore not
suitable for cable transmission in an industrial environment!
NOTE
Ex factory both switches are OFF, i.e. any single-ended operation requires HTL
levels (this is the normal case).
MAN IF10 I_E 1.1.odt
5 - Electrical connections
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