6RA70 converters are supplied with parameters set to the factory settings. Automatic optimization runs can be selected by means of special key numbers to support setting of the controllers.
The following controller functions can be set in an automatic optimization run:
- Current controller optimization run for setting current controllers and feedforward controls (armature and field circuit).
- Speed controller optimization run for setting characteristic data for the speed controller.
- Automatic recording of friction and moment of inertia compensation for feedforward control of speed controller.
- Automatic recording of the field characteristic for an e.m.f.-dependent closed-loop field-weakening control and automatic optimization of the e.m.f. controller in field-weakening operation.
Furthermore, all parameters set automatically during optimization runs can be altered afterwards on the operator panel.
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.
The trace function can be selected to store up to 8 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.
A number is allocated to each fault message. The time at which the event occurred is also stored with the fault message. This allows the cause of the fault to be pinpointed promptly. The most recent eight 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 I = 0, pulse disable, relay “Line contactor CLOSED” drops out) and
- An “F” with a fault number appears on the display, the “Fault” LED lights up.
- Fault messages can be acknowledged on the operator panel, via a binary assignable-function terminal or a serial interface. When a 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 2s. 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 to supplementary boards are malfunctioning
- Drive fault: Monitor for speed controller, current controller, e.m.f. controller, field current controller has responded, drive blocked, no armature current
- Electronic motor overload protection (I2t 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 only occur 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): Monitoring of brush length, bearing condition, air flow, motor temperature has responded
- External faults via binary assignable-function terminals.
Fault messages can be deactivated individually. The default setting for some fault messages is “deactivated” so they need to be activated in the appropriate parameter.
Special states that do not lead to drive shutdown are indicated by alarms. Alarms do not 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 (with terminal expansion option only): Monitoring 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.
Safety shutdown (E-STOP)
The task of the E-STOP function is to open the relay contacts (terminals 109/110) for energizing the main contactor within about 15 ms, independently of semiconductor components and the functional status of the microprocessor board (basic electronics). If the basic electronics are operating correctly, the closed-loop control outputs an I = 0 command to de-energize the main contactor. When an E-STOP command is given, the drive coasts to a standstill.
The E-STOP function can be triggered by one of the following methods:
- Switch operation: E-STOP is activated when the switch between terminals 105 and 106 opens.
- Pushbutton operation: Opening an NC contact between terminals 106 and 107 triggers the E-STOP function and stores the shutdown operation. Closing an NO contact between terminals 106 and 108 resets the function.
When the E-STOP function is reset, the drive switches to the “Starting lockout” state. This status needs to be acknowledged through activation of the “Shutdown” function, e.g. by opening terminal 37.
Note: The E-STOP function is not an
EMERGENCY STOP function according to
The following serial interfaces are available:
- One serial interface on connector X300 on the PMU for a USS protocol to the RS 232 or RS 485 standard. For connection of optional OP1S operator panel or for PC-based DriveMonitor.
- One serial interface at terminals of the basic electronics board, two-wire or four-wire RS485 for USS protocol or peer-to-peer connection.
- One serial interface at terminals of the terminal expansion board (option), two-wire or four-wire RS485 for USS protocol or peer-to-peer connection.
- PROFIBUS-DP on a supplementary card (option).
- SIMOLINK® on a supplementary card (optional) with fiber-optic connection.
Physical characteristics of interfaces
RS 232: ±12 V interface for point-to-point operation.
RS 485: 5 V normal mode interface, noise-proof, for an additional bus connection with a maximum of 31 bus nodes.
Disclosed SIEMENS protocol, easy to program on external systems, e.g. on a PC, any master interfaces can be used. The drives operate as slaves on a master. The drives are selected via a slave number.
The following data can be exchanged via the USS protocol:
PKW data for writing and reading parameters.
PZD data (process data) such as control words, setpoints, status words, actual values.
Connector numbers are entered in parameters to select the transmit data (actual values), the receive data (setpoints) represent connector numbers that can be programmed to act at any intervention points.
The peer-to-peer protocol is used to link one converter to another. With this mode, data are exchanged between converters, e.g. to build a setpoint cascade, via a serial interface. Since a serial interface is employed as a four-wire line, it is possible to receive data from the upstream converter, condition them (e.g. through multiplicative weighting) and then send them to the downstream converter. Only one serial interface is used for the whole operation.
The following data can be exchanged between converters:
- Transmission of control words and actual values.
- Receipt of status words and setpoints.
Up to five data words are transmitted in each direction. Data are exchanged on the basis of connector numbers and intervention points.
The serial interfaces can be operated simultaneously. For example, the first interface can be used as an automation link (USS protocol) for open-loop control, diagnostics and specification of the master setpoint. A second interface operates in conjunction with the peer-to-peer protocol to act as a setpoint cascade.