SIMOREG 6RA70 Siemens DC Master Variable Speed DC Drive
Design & Mode of Operation
– Monitoring & Diagnosis

Design and Mode of Operation6RA70 DC Master

Monitoring and diagnosis

Display of operational data

The operating status of the converter is displayed via parameter r000. Approximately 50 parameters are provided for displaying measured values. An additional 300 signals from the closed-loop control can be selected in the software (connectors) for output on the display unit. Examples of displayable measured values: Setpoints, actual values, status of binary inputs/outputs, line voltage, line frequency, firing angle, inputs/ outputs of analog terminals, input/output of controllers, display of limitations.

Trace function

The trace function can be selected to store up to 10 measured quantities with 128 measuring points each. A measured quantity or the activation of a fault message can be parameterized as a trigger condition. It is possible to record the pre-event and post-event history by programming a trigger delay. The sampling time for the measured-value memory can be parameterized to between 3 and 300 ms.

Measured values can be output via the operator panels or serial interfaces.

Fault messages 

A number is allocated to each fault message. The time at which the event occurred is also stored with the fault message, allowing the fault cause to be pinpointed promptly. The most recent 8 fault messages are stored with fault number, fault value and hours count for diagnostic purposes.

When a fault occurs

  • the binary output function “Fault” is set to LOW (selectable function),
  • the drive is switched off (controller disable and current f = 0, pulse disable, relay “Line contactor CLOSED” drops out) arid
  • an F with a fault number appears on the display, LED “Fault” lights up.

Fault messages can be acknowledged on the operator panel, via a binary assignable function terminal or a serial interface. When the fault has been acknowledged, the system switches to the “Starting lockout” status. “Starting lockout” is cancelled by OFF (L signal at terminal 37).

Automatic restart: The system can be restarted automatically within a parameterizable time period of 0 to 2 s. If this time is set to zero, a fault message is activated immediately (on power failure) without a restart. Automatic restart can be parameterized in connection with the following fault messages: Phase failure (field or armature), undervoltage, overvoltage, failure of electronics power supply, undervoltage on parallel SIMOREG unit.

Fault/error messages are divided into the following categories:

  • Line fault: Phase failure, fault in field circuit, undervoltage, overvoltage, line frequency < 45 or > 65 Hz
  • Interface fault: Basic unit interfaces or interfaces to supplementary boards are malfunctioning.
  • Drive fault: Monitor for speed controller, current controller, EMF controller, field current controller has responded, drive blocked, no armature current
  • Electronic motor overload protection (Pt monitor for motor) has responded
  • Tacho-generator monitor and overspeed signal
  • Start-up error
  • Fault on electronics board
  • Fault message from thyristor check: This fault message will occur only if the thyristor check is activated via the appropriate parameter. The check function ascertains whether the thyristors are capable of blocking and firing.
  • Fault messages from motor sensors (with terminal expansion option); Monitor of brush length, bearing condition, air flow, motor temperature, has responded
  • External faults via binary as signable-function terminals

Fault messages can be deactivated individually. The default setting for some fault messages is “deactivated” so that they need to be activated in the appropriate parameter.


Special states are indicated by alarms. These states do not lead to drive shutdown nor do the alarms need to be acknowledged, but are automatically reset when the cause of the problem has been eliminated.

When one or several alarms occur,

  • the binary output function “Alarm” is set to LOW (selectable function) and
  • the alarm is indicated by a flashing “Fault” LED.

Alarms are divided into the following categories:

  • Motor overtemperature: The calculated I2t value of the motor has reached 100 %.
  • Alarms from motor sensors (only with terminal expansion option): Monitor of bearing condition, motor fan, motor temperature, has responded.
  • Drive alarms: Drive blocked, no armature current.
  • External alarms via binary assignable-function terminals.
  • Alarms from supplementary boards.


Siemens Energy & Automation
SIMOREG DC Master Base Drive Operating Instructions