User Manual

Bosch Rexroth AG 5/12
RE 95132/11.08
DSM Series 10
Output signals
The output signal of the DSM1-10 consists of square-wave
pulses of a constant amplitude, which are generated by the
evaluation electronics of the DSM1-10. The length of the indi-
vidual pulses provides information about the direction of rotation
and any errors that there may be in the installation position.
The evaluation electronics generate a high pulse of a certain
length after every flank of the internal sensor speed signal.
The length of the pulse is determined by the information to be
transmitted. For example, the information ‘counter-clockwise
rotation’ is described by a pulse 90 µs long, and the information
‘clockwise rotation’ by a pulse 180 µs long.
In order to ensure that the speed information can still be emit-
ted at higher speeds even when pulses are longer, a low time
(prebit low) is always placed ahead of the high pulse. So, the
additional information from the signal is lost at high speeds
(pulses are cut off by the low time), but the actual speed
information can be output reliably up to a very high frequency
(upstream low time + shortest high pulse).
If the air-gap reserve signal (AR) is emitted, the other signals
are
overshadowed (AR is dominant), i. e.neither a direction of
rotation signal (DR) nor the installation position si
gnal (MP)
is emitted above the air-gap reserve threshold.
Signal form
Transmitted signal: LR
Transmitted signal: DR counter-clockwise
Transmitted signal: DR counter-clockwise and EL
Transmitted signal: DR clockwise
Transmitted signal: DR clockwise rotation and EL
Sensor internal rotary signal (corresponds to gear)
Prebit low = LR width
LR width = 45 ms typical
DR L width = 2x LR width
DR R width = 4x LR width
DR L and EL width = 8x LR width
DR-R and EL width = 16x LR width
X
n+1
X
n+2
X
n