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Cube67 System Manual
31 V 2.5
3.5.2 Grounding
A short and low impedance connection between the grounding terminal and ground is required to draw off
interference voltages occurring between the device and ground. The inductance of conventional FE
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cables is a source of high impedance for high-frequency interference voltages. For this reason, the use of
grounding strips is preferred. If this is not possible, use a fine-stranded FE cable of large cross-section
and keep the distance to ground as short as possible.
3.5.3 Cable Routing
A frequent cause of EMC problems is failure to observe the elementary rules of cable routing.

The field bus line must be laid as far away from power lines as possible.

A minimum distance of 10 cm must be maintained.

Data lines and power lines should only cross at right angles.
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It is recommended that data lines and power lines be laid in separate and shielded conduits.
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The interference potential of other devices or lines must be taken into account when laying cables.
The greatest possible distance must be maintained to frequency inverters, motor lines and other
devices, or lines which emit high frequency interference.
3.5.4 Voltage Drops
The power supply to the electronics is buffered by means of integrated capacitors so that a short-term
voltage drop will not usually affect normal operation. This does not apply to sensors and actuators
connected to the Cube67 as their high power requirements cannot be buffered by integrated capacitors.
Even a short-term interruption in actuator power supply can therefore result in undesired switching
operations.
Interruption of the sensor supply voltage < 1 ms does not result in any change to the input status reported
to the DP Master, thanks to the integrated input filter. Lengthier sensor supply interruptions, however, can
lead to a signal change at the inputs.
3.5.5 Separate Power Supplies
Sensors or actuators can be supplied with power from a common source. For maximum electromagnetic
compatibility throughout the system, however, separate power supplies are advisable.
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FE Function Ground