Free function blocks

Application, properties

Logic operations which link several states (e.g. access control, plant status) to a control signal (e.g. ON command) are required for controlling the drive system in a wide variety of applications. Along with logic operations, a number of arithmetic operations and storing elements are becoming increasingly important in drive systems.

This functionality is available as function module "Free function blocks" (FBLOCKS) for SINAMICS DC MASTER and can be activated in the Control Unit (CUD). A detailed description is provided in the Function Manual "Free Function Blocks" (see under “Services and documentation”).

Configuring and use

The free function blocks are configured at the parameter level.

The following parameters are required for this:

• Input parameters (e.g. inputs I0 ... I3 for the AND function block)
• Output parameters (e.g. output Y for the numeric change-over switch)
• Adjustable parameters (e.g. pulse duration for pulse generator MFP)
• Runtime group (this includes the sampling time; the free function blocks are not computed in the factory setting)
• Run sequence within the runtime group

A parameter is assigned to each input, output, and setting variable. These can be accessed by means of the AOP30 Advanced Operator Panel or STARTER commissioning software. The free function blocks can be interconnected at the BICO level. The free function blocks do not support data set dependency.

Range of blocks

The table below shows the range of free function blocks available. The special technical properties of the individual function blocks can be taken from the function block diagrams in Chapter 3 of the Function Manual.

Drive Control Chart (DCC)

The "Drive Control Chart" function (DCC) is available for more complex applications.

DCC allows you to graphically configure the required functionality and then download it to the drive. It provides a significantly extended range of block types available.

In online operation, the signal values can be monitored in STARTER/SCOUT in the DCC chart.

Power section and cooling

SINAMICS DC MASTER converters distinguish themselves as a result of the compact, space-saving design. The electronics module (available in various customer-specific combinations with options) is installed in a cradle that can be swiveled out. The easy access to individual components makes this technology very service-friendly.

Plug-in terminals are used to connect external signals (binary inputs/outputs, analog inputs/outputs, pulse generators etc.). The firmware is saved in a flash EPROM and can be easily exchanged by loading via the serial interface of the SINAMICS DC MASTER.

Power section: Armature and field circuit

The armature circuit is implemented as a three-phase bridge circuit:

• For units for two-quadrant operation, in a fully-controlled three-phase bridge circuit B6C
• For units for four-quadrant operation in two fully-controlled three-phase bridge circuits (B6) A (B6) C.

The field circuit is implemented in a half-controlled single-phase bridge circuit B2HZ.

In the case of units with a 15 A to 1200 A rated DC current, the power sections for the armature and field include electrically isolated thyristor modules, which means that the heat sink is floating. For units up to 30 A, the armature and field power sections are implemented in the form of a printed circuit board with compact modules that are soldered on.

For units with rated currents ? 1500 A, the power section for the armature circuit uses disc-type thyristors and heat sinks at voltage potential. For units from 1500 to 3000 A, the thyristor phases are implemented as plug-in modules and can therefore be quickly replaced.

Checking the motor insulation has been significantly simplified due to the fact that the line supply voltage sensing for the armature and the field sections is electrically isolated.

Cooling

Units with a rated DC current up to 125 A are designed for natural air cooling, units with a rated current above 210 A are designed for forced air cooling (fan). The fans are always horizontally mounted at the top so that they can be quickly replaced without having to disconnect the power connections.

Parameterizing devices

BOP20 Basic Operator Panel

BOP20 Basic Operator Panel

As standard, all of the units are equipped with a BOP20 Basic Operator Panel from the SINAMICS family.

The basic operator panel offers customers a basic functionality for commissioning as well as operator control and monitoring.

Faults can be acknowledged, parameters set and diagnostics information read-out (e.g. alarm and fault messages) using the BOP20.

The BOP20 has a backlit two-line display area and 6 keys.

The BOP20 power supply and communication with the CUD Control Unit are established via the connector integrated at the rear of the BOP20.

AOP30 Advanced Operator Panel

The AOP30 Advanced Operator Panel is an optional input/output device for SINAMICS DC MASTER converters. It can be separately ordered. You will find additional information about the AOP30 in section "Accessories and supplementary components".

PC based parameterization

The STARTER tool is available for PC-based commissioning and diagnostics. More detailed information is provided in section “Tools and engineering”.

Closed-loop control and open-loop drive control

The closed-loop control and open-loop drive control is essentially designed for supplying the armature and field of variable-speed DC drives.

Using BICO technology permits the closed-loop and open-loop drive control structure to be simply adapted to the application-specific requirements as well as the use in alternative applications (e.g. as excitation equipment for synchronous motors).

The most important functions of the closed-loop control include:

• Setpoint processing (including digital setpoints, jogging, motorized potentiometer)
• Ramp-function generator
• Speed controller actual value processing
• Speed controller
• Torque and armature current control
• Closed-loop armature current control
• Armature gating unit
• Closed-loop EMF control
• Closed-loop field current control
• Field gating unit

BICO technology

BICO technology (Binector Connector Technology) allows signal paths to be defined (and therefore the controller structure) using parameters.

Mode of operation:
All important points of the closed-loop control are accessible via connectors.
Connectors are measuring points that are mapped to display parameters.

Important connectors include:

• Analog inputs and outputs
• Interface inputs (e.g. PROFIBUS)
• Actual value sensing inputs (e.g. speed, armature current, armature voltage)
• Inputs and outputs of the ramp-function generator, speed controller, armature current controller, armature gating unit, EMF controller, field current controller, field gating unit
• General quantities such as operating state, motor temperature rise, thyristor temperature rise

All important binary signals of the closed-loop and open-loop control are accessible via binectors.
Binectors are measuring points for binary signals, which are mapped to display parameters.

Important binectors include:

• Status of binary inputs
• Control words, status words
• Status of controllers, limits, faults

All of the important inputs of the open-loop and closed-loop control can be interconnected using BICO selection parameters. This means that by setting the corresponding BICO selection parameter, a connection can be established between any connector or binector.

Important inputs include:

• Setpoint input, supplementary setpoint input
• Ramp-function generator input
• Speed controller input
• Armature current controller input
• Armature gating unit input
• Speed setpoint limiting (before and after the ramp-function generator)
• Torque limiting
• Armature current limiting
• Signal source for binary and analog outputs

Data sets

Many open-loop and closed-loop control parameters depend on the particular data set. This means that they have several indices where various values can be set. All data set dependent parameters can be simultaneously switched over to another data set using binary control signals.

There are two groups of data set-dependent parameters:

• DDS parameters:
  Parameters that are associated with the drive data set (DDS). The drive data set contains various adjustable parameters that are relevant for open-loop and closed-loop drive control.
• CDS parameters:
  Parameters that are associated with the command data set (CDS). Many BICO selection parameters are combined in the command data set. These parameters are used to interconnect the signal sources of a drive.

By parameterizing several command data sets and switching between them, the drive can be operated with different pre-configured signal sources.

Optimization run

The SINAMICS DC MASTER converter units are supplied with the factory settings. Controller setting is supported by selecting automatic optimization runs. The selection is made using special key numbers.

The following controller functions can be set using an automatic optimization run:

• Current controller optimization run to set the current controller and pre-controls (armature and field circuit).
• Speed controller optimization run for setting the speed controller characteristics; automatic recording of the friction and moment of inertia compensation for the speed controller pre-control.
• Automatic recording of the field characteristic for an EMF-dependent field-weakening control and automatic optimization of the EMF controller for field-weakening operation.
• In addition, all of the parameters set during the automatic optimization runs can be changed via the operator panel.

Monitoring and diagnostics

Displaying operating values

The operating state of the converter is displayed using a parameter. Several hundred signals can be displayed via parameter or selected for output on the display unit. Examples of measured values that can be displayed: Setpoints, actual values, status of binary inputs/outputs, line supply voltage, line frequency, firing angle, inputs/outputs of the analog terminals, controller input and output, limits.

Trace function

Up to eight measured quantities can be saved by selecting the trace function. A measured quantity or the occurrence of a fault message can be parameterized as trigger condition. By selecting a trigger delay, it is also possible to record (trace) the pre-history and post-history of events. The sampling time of the measured value storage can be parameterized.

The measured values can be output via the serial interfaces using the STARTER commissioning tool.

Fault messages

A number is assigned to each fault message. In addition, the operating hour of the event is saved together with the fault message. This allows the cause of the fault to be quickly pinpointed. By using the optional AOP30 Advanced Operator Panel, fault messages can be stamped in real time. Then, instead of the operating hour of the event, the day and the time of day of the event is displayed in the AOP30 fault list. For diagnostic purposes, the last eight fault messages are saved with fault number, fault value and the operating hours.

When a fault occurs

• the binary output function "Fault" is set to LOW (user-assignable function),
• the drive is switched-off (controller inhibit, current I = 0 is entered, pulses are inhibited, the relay "line contactor CLOSE" drops out) and
• an F is displayed with fault number, LED "Fault" is lit.

Fault messages should either be acknowledged via the operator panel, a binary user-assignable terminal or a serial interface. The "switch-on inhibit" state is reached after the fault has been acknowledged. "Switch-on inhibit" is canceled by an OFF command.

Automatic restart: An automatic restart is possible within a time that can be parameterized between 0 and 10 s. If the time is set to zero, a fault message is immediately output (for power failure) without a restart. A restart can be selected for the following fault messages: Phase failure (field or armature), undervoltage, overvoltage, electronics power supply failure, undervoltage condition at the parallel SINAMICS DC MASTER.

A distinction is made between the following groups of fault messages:

• Power system faults: Phase failure, fault in the field circuit, undervoltage, overvoltage, line frequency < 45 or > 65 Hz
• Interface faults: CUD interfaces or interfaces to the supplementary boards faulted
• Drive faults:
  Controller monitoring for speed controller,
  Current controller, EMF controller,
  Field current controller has responded,
  Drive stalled,
  No armature current possible
• Electronic motor overload protection (I²t monitoring of the motor has responded)
• Tachometer monitoring and overspeed signal
• Commissioning fault
• Fault on the electronics module
• Fault message from the thyristor check: This fault message can only occur if the thyristor check has been activated using the appropriate parameter. In this case, a check is made as to whether the thyristors can be blocked and whether they can be fired.
• Fault messages from the motor sensor system:
  Monitoring of brush length, bearing condition, air flow, motor temperature
• External faults via binary user-assignable terminals

The fault messages can be individually deactivated using a parameter. Some fault messages are already deactivated in the factory and can be activated using this parameter.

Alarms

Alarm messages display special states; however, they do not cause the drive to be switched-off. Alarms that occur do not have to be acknowledged, but rather they are automatically reset as soon as the cause of the alarm is no longer present.

When one or several alarms occur

• the binary output function "Alarm" is set to LOW (user-assignable function) and
• the alarm is displayed by the flashing "Fault" LED.

A distinction is made between the following groups of alarms:

• Motor overtemperature: The calculated I²t value of the motor has reached 100 %.
• Alarms from the motor sensor system: Monitoring of brush length, bearing condition, motor fan, motor temperature
• Drive alarms: Drive has stalled, no armature current possible
• External alarms via binary user-assignable terminals
• Alarms from supplementary modules

Functions of the inputs and outputs

Analog user-assignable inputs

After converting to a digital value, the quantity of the analog inputs can be flexibly adapted via parameters for scaling, filter, sign selection and offset input. The values are available as connector. This is the reason that the analog inputs can be effective as main setpoint and also as quantity for a supplementary setpoint or a limit.

Analog outputs

Selectable analog outputs are available to output analog signals. Analog signals can be output as bipolar signal or as absolute value. In this case, scaling, an offset, polarity and a filter time can be parameterized. The required output quantities are selected at the intervention points by entering connector numbers. For instance, speed actual value, ramp-function generator output, current setpoint, line supply voltage etc. can be output.

Binary inputs

• Switch-on/shutdown (OFF 1)
  This terminal function is ANDed with the control bit of the serial interface. For an H signal at terminal switch-on/shutdown, the main contactor closes via an internal sequence control. The controllers are enabled if there is an H signal at the operating enable terminal. The drive accelerates up to the operating speed with the speed setpoint. For an L signal at the terminal switch-on/shutdown, the drive is ramped down to speed n < n_min via the ramp-function generator; after the brake control delay time, the controllers are inhibited and at I = 0, the main contactor is opened. After this, after an adjustable time after the main contactor has dropped out, the field current is reduced to the standstill field current (this can be parameterized). The standstill field can e.g. be used as anti-condensation heating for the motor; to do this, approximately 30 % of the rated field current must be entered as standstill field. The motor fan must be operational for a field current of 100 % of the rated field current. Otherwise, the field winding will be overloaded.
• Operating enable
  This function is ANDed with the control bit of the serial interface. The controllers are enabled with an H signal at the operating enable terminal. For an L signal, the controllers are inhibited and at I = 0, the pulses are inhibited. The signal operating enable has a high priority; this means that if the signal (L signal) is withdrawn in operation, then this always results in I = 0 and therefore the drive coasts down.

Binary user-assignable inputs:
Additional binary input terminals are available for user-assignable functions. In this case, a binector number is assigned to every user-assignable terminal, which can be used for control functions.

Examples of binary input functions:

• Voltage disconnect (OFF 2): For OFF 2 (L signal), the controllers are instantaneously inhibited, the current in the armature circuit is reduced and at I = 0, the main contactor is opened. The drive coasts down uncontrolled.
• Quick stop (OFF 3): For a quick stop (L signal), the speed setpoint at the speed controller input is set to zero and the drive is braked along the current limit for quick stop (parameterizable). At n < n_min after the brake control delay time I = 0 is entered and the main contactor is opened.
• Jogging: The jogging function is available for an L signal at terminal switch-on/shutdown, for an H signal at terminal operating enable and when the jogging function is controlled. In this case, the main contactor is closed and the drive accelerates up to the jogging setpoint defined in a parameter. When the jogging signal is withdrawn, the drive is braked to n < n_min; after this, the controllers are inhibited and the main contactor is opened after a parameterizable time (0 to 60 s). Further, it can be selected as to whether the ramp-function generator is active or ramp-up time = ramp-down time = 0 is used.

Binary outputs

User-assignable signaling functions are available at the binary output terminals (open emitter output). Any binector quantity, which can be selected via the associated user-assignable parameter, can be output for each terminal. The polarity of the output signal and an adjustable delay time (0 to 10 s) can be selected using parameters.

Examples of binary output functions:

• Fault: An L signal is output when a fault message is present.
• n < n_min: An H signal is output for speeds less than n_min. This signal is used, for instance, as a zero speed signal.
• Switch-on command for a mechanical brake: A motor brake can be controlled using this signal.

When switching on the drive using the "switch-on" function and entering "operating enable", an H signal is output to open the brake, in this case, the internal controller enable is delayed by a parameterizable time (wait for the mechanical brake opening time to expire). When shutting down the drive using the "shutdown" function or "quick stop", an L signal is output to close the brake when speed n < n_min is reached. At the same time, the internal controller enable is present for a parameterizable time (wait for the mechanical brake closing time to expire): When I = 0 is entered, the pulses are inhibited and the main contactor is opened.

An additional operating mode can be selected using the "close brake" signal (L signal at the binary user-assignable output). As a consequence, when the "internal controller inhibit" is present (the drive is in a no-current condition), the drive does not wait for the status n < n_min, but the brake is already controlled (operating brake) at speeds greater than n_min.

Internal control inhibit is present when a fault message occurs, when the voltage is disconnected or the operating enable - terminal operating enable - is withdrawn in operation.

Safety shutdown (E-STOP)

The E-STOP function is used to open the relay contact for the main contactor control within approximately 15 ms independently of semiconductor components and the correct functioning of the CUD. If the CUD is operating correctly, entering I = 0 via the control ensures that the main contactor is switched in a no-current condition. The drive coasts down once E-STOP has been entered.

After the E-STOP has been reset, the drive goes into the "switch-on inhibit" operating state. This must be acknowledged by activating the "shutdown" function e.g. by opening terminal switch-on/shutdown.

Note:
The E-STOP function is not an EMERGENCY OFF function in the sense of EN 60204-1.

Serial interfaces

The following serial interfaces are available for each CUD:

• A serial interface on the Standard CUD and Advanced CUD for the USS protocol according to RS232 or RS485 to connect the optional AOP30 Advanced Operator Panel or for STARTER via a PC.
• A serial interface at the terminals of the Standard CUD and Advanced CUD, RS485 two-wire or four-wire for a peer-to-peer connection.
• PROFIBUS DP as standard on the Standard CUD and Advanced CUD
• PROFINET via the CBE20 Communication Board on the Advanced CUD (option)
• EtherNet/IP via the CBE20 Communication Board on the Advanced CUD (option)
• DRIVE-CLiQ on Advanced CUD (option) to connect optional SINAMICS components SMC30, TM15, TM31 and TM150

Physics of the interfaces

• RS232: ± 5 V interface for the point-to-point connection
• RS485: 3.3 V common mode interface, interference-proof, additionally for one bus connection with a maximum of 31 participants connected to the bus

USS protocol

Open Siemens protocol, can be simply programmed e.g. on the PC in third-party systems, any master interfaces can be used. The drives operate as slaves connected to a master. The drives are selected using a slave number.

The following data exchange is possible via the USS protocol:

• PKW data to read and write parameters
• PZD data (process data) such as control words, setpoints, status words, actual values

The send data (actual values) are selected by entering connector numbers in the parameters, the receive data (setpoints) represent the connector numbers, that can act at any intervention points.

Peer-to-peer protocol

The peer-to-peer protocol is used to connect devices with one another. For this operating mode, data is exchanged between converters via a serial interface, e.g. to establish a setpoint cascade. By using a serial interface as four-wire cable, data can be received from the previous unit that is then processed (e.g. by being multiplied) and then transferred to the following unit. Only one serial interface is used for this purpose.

The following data can be exchanged between converters:

• Sending control words and actual values.
• Receiving status words and setpoints.

In this case, up to five data words are transferred in both the send and receive directions. Data is exchanged via connector numbers and intervention points.

The serial interfaces can be simultaneously operated. A connection to the automation (USS protocol) can be established via the first interface for control, diagnostics and to enter the main setpoint. A second interface is used to realize a setpoint cascade function via the peer-to-peer protocol.

Control terminal block

Interface to the motor

Motor temperature monitoring

Either PTC thermistors or linear temperature sensors (KTY84-130) can be connected. One input is provided on the Standard CUD and one input on the Advanced CUD option for this purpose. An alarm or fault message can be parameterized for PTC thermistors. When using a KTY84-130, one threshold can be entered for an alarm and one threshold for shutdown (trip). The limit values are displayed and entered in °C.

In addition, a thermo switch can be evaluated by the Advanced CUD (option). A parameterizable alarm or fault message can be output when the thermo switch responds (this is a binary switching signal). The evaluation is realized via a binary user-assignable input.

Brush length monitoring

The brush length is monitored using a floating microswitch; the shortest brush is evaluated. If the useful brush life has expired, then the microswitch opens; an alarm or fault message can be parameterized. The evaluation is realized via a binary user-assignable input.

Monitoring the motor fan airflow

The airflow is monitored by an airflow monitor integrated in the airflow circuit of the motor fan. When this responds, an alarm or fault message is issued. The evaluation is realized via a binary user-assignable input.

Siemens DC motors

Although the end of DC technology has been forecast now for many years, we will keep hold of our DC technology and it will remain in our portfolio. When all is said and done, DC motors have proven themselves in daily use for decades now and they are essentially indispensable.

In conjunction with the SINAMICS DC MASTER converters, they always form the ideal team – wherever favorably-priced drive technology and the highest degree of availability are demanded.

These motors can also be used where space is restricted thanks to their compact and modular design.

Further, an extensive range of equipment and devices for mounting on the motor is available. A wide range of monitoring and diagnostic options facilitate reliable and disturbance-free operation.

Detailed specifications regarding quality assurance and improvement are integrated in all of the various operations and processes - from motor development through to production and service. Quality management coordinates the interaction between all of the company processes to ensure error-free and smooth processes.

It goes without saying that our stringent quality requirements also apply to our suppliers. All of the suppliers must seamlessly integrate themselves into our quality management system.

The result: Only fault-free and high quality materials are released for use in our motor production.

Customer benefits:

• High power density with low envelope dimensions
• High degree of operational reliability and availability through a wide range of diagnostic features, in conjunction with the SINAMICS DC MASTER converter
• High thermal reserves for continuous and overload conditions as a result of the DURIGNIT 2000^® insulation system
• Low losses through a very good efficiency
• Long brush lifetimes through an optimized current commutation system

Typical applications:

• Lift and cableway drives
• Rolling mill drives and winders
• Hoisting and travel gear drives for cranes
• Extruders in the plastics industry
• Drives for printing machines
• Drives for paper machines

Additional information on Siemens DC motors is available on the Internet under:
http://www.automation.siemens.com/ld/dc-motor