CNCdrive DG4S Series, Manual

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14 CONTENTS
To protect your new drives and also for the most reliable communications between the
computer and the CNC electronics, always use separated Power Supplies for the digital
power and the motor power and do not connect the two GND points together,
keep them
separated and run the ground lines back to their respective power supplies.
Use shielded cables for the Main connector and Encoder connector if possible. Connect
the cable shields to an earth GROUND point (PE) at one end only, preferably at the Control
box and not at the machine tool.
If connecting both ends of a cable shield to ground, then current can flow thru the shield
creating noise problems and also can carry high voltage back to your control box elec-
tronics in the event of a short circuit at the machine tool.
5.4 Error Line wiring
The Error line is a bidirectional line and when looking to it as an output it acts as an open-
collector output.
While the drive is running in normal operation the error line is released by the drive and
only the internal ~100kOhm pullup resistors pulling the line to the internal 5 Volts potential.
The error line acts as an open collector output means that any number of error lines can
be paralleled (connected together) which allows the user to create a “common error line”.
When paralleling the error lines of all drives in a setup, if any of the drive has an internal
fault, it pulls the error line low indicating the fault and stopping all other drives.
An external optical isolator may be used to interface the error line to the control computer
or to a PLC or to any type of external control circuit. The external optical isolator may be
connected as drawn on Figure 5.
An external pushbutton or NPN transistor may be used to trigger the error line by external
circuits.
Take care to not to overstress the Error line output and never connect the error line to any
other potential than GND (0 Volts of the digital powersupply).
The error line can sink a maximum 50mAmpers of current and can live throu 100mA in
peaks.
Overstressing the error line may cause permanent damage to the device!