Unidrive M / HS Frame 7 to 10 Power Installation Guide 91
Safety information Product information Mechanical installation
Electrical installation
Technical data UL listing information
Figure 4-27 Surge suppression for digital and unipolar inputs and outputs
Figure 4-28 Surge suppression for analog and bipolar inputs and outputs
Surge suppression devices are available as rail-mounting modules, e.g. from Phoenix Contact:
Unipolar TT-UKK5-D/24 DC
Bipolar TT-UKK5-D/24 AC
These devices are not suitable for encoder signals or fast digital data networks because the
capacitance of the diodes adversely affects the signal. Most encoders have galvanic isolation of the
signal circuit from the motor frame, in which case no precautions are required. For data networks,
follow the specific recommendations for the particular network.
Signal from plant Signal to drive
0V 0V
30V zener diode
e.g. 2xBZW50-15
Signal from plant Signal to drive
0V 0V
2 x 15V zener diode
e.g. 2xBZW50-15