HEIDENHAIN PWM 20 - Manual (Page 214)

November 2014 Interface description 215
7.2.3 Incremental signals 1Vpp with commutating signals
Examples of
encoders ERN 1085, ERN 1185, ERN 1387
Commutating
signals The commutating signals C and D are derived from the Z1 track, and are equal to one sine or
cosine period per revolution. Their typical signal amplitude is 1 Vpp (signal level: see incremental
signals A and B). The recommended input circuit of the subsequent electronics is the same as
for the 1 Vpp interface.
Incremental signals Two nearly sinusoidal signals A and B
Reference mark
signal One or several signal peaks R
Connecting cables
Signal amplitude M 0.75 to 1.2 Vpp
typ. 1 Vpp
Asymmetry /2M 0.05 TV
11.5°
Signal ratio M
A
/ M
B
0.9 to 1.1
Phase angle /2 90°
5° el.
P - N =ˆ
1 2
+
Usable component G 0.2 to 1.1 V
Signal-to-noise ratio E, F min. 100 mV
Zero crossovers K, L 180°
 90° el.
Shielded HEIDENHAIN cable PUR [4(2 x 0.14 mm
2
) + (4 x 0.5 mm
2
)]
Cable length Max. 150 m at 90 pF/m distributed
capacitance
Propagation time 6 ns/m