HEIDENHAIN PWM 20 - Manual (Page 216)

November 2014 Interface description 217
Signal data
Connecting cables
Differential line driver
as per EIA standard RS-422
Signal level U
H
2.5 V with
I
H
= 20 mA
U
L
0.5 V with I
L
= 20 mA
Permissible load R 100
 (between associated outputs)
Max. load per output 20 mA
Capacitive load C
load
1000 pF with respect to 0 V
Short-circuit stability Outputs protected against short circuit to 0 V
Switching times (10 % to 90 %)
with 1 m cable and recommended
input circuit Rise time
t
+
30 ns
Fall time
t
 30 ns
>
<
>
I
L
<
<
<
<
Shielded HEIDENHAIN cable PUR [4(2 x 0.14 mm 2 ) + (4 x 0.5 mm 2 )]
Cable length Max. 100 m (UaS max. 50 m) with 90 pF/m
distributive capacitance
Propagation time 6 ns/m