SEW MOVIDRIVE bus positioning

SEW MOVIDRIVE ®  Bus Positioning: A Complete Guide to Project Planning, Installation, Debugging, and Troubleshooting

Introduction

In modern automation systems, precise positioning is a key technology in areas such as material handling, warehousing logistics, and robotics. SEW-EURODRIVE for MOVIDRIVE ®  The MDV60A/MDS60A frequency converter provides Bus Positioning based on fieldbus or system bus, which is integrated into the MOVITOOLS software package as an IPOSplus program and can achieve multi axis position control without complex programming. This article is based on the official supplementary explanation (document number 0918 421x, 2018-2020 version), which systematically explains the application scenarios, hardware requirements, installation and wiring, startup and debugging, parameter configuration, and typical fault handling of bus positioning, providing engineers with a complete technical operation manual.

Project Planning

1.1 Application Fields

Bus positioning is particularly suitable for the following industries and scenarios:

Material handling: electric hoist, rail vehicle, shuttle car

Logistics warehousing: elevated warehouse stacker crane, horizontal moving trolley

Stacking/handling: Multi axis robotic arm, gantry frame

Its core advantages lie in a user-friendly interface, requiring only basic parameters (speed ratio, diameter, speed) to be entered, no programming experience required, supporting monitoring mode diagnosis, and quick start-up.

1.2 Software and hardware requirements

1.2.1 PC and Software

Operating System: Windows 95/98/NT 4.0

Software: MOVITOOLS (including bus positioning program)

1.2.2 Frequency converter, motor and encoder

Variable frequency drive type:

MOVIDRIVE ®  MDV60A (asynchronous servo/AC motor)

MOVIDRIVE ®  MDS60A (synchronous servo motor)

Fieldbus option card (installed in OPTION1 slot):

PROFIBUS → DFP11A

INTERBUS → DFI11A

CAN bus → DFC11A

DeviceNet → DFD11A

System bus SBus (standard, no option card required)

Motor and Feedback:

MDV60A+CT/CV asynchronous servo motor (with built-in encoder)

MDV60A+DT/DV/D AC motor (requires incremental encoder or combination encoder AV1Y)

MDS60A+DS/DY synchronous servo motor (with built-in rotary transformer)

External encoder (required for non rigid connections):

Incremental encoder → connected to basic unit X14

Absolute value encoder → connected to DIP11A option card X62

If it is a rigid connection (no relative sliding between the motor shaft and the load), an external encoder is not required; But external encoders can also be configured in a non rigid connection manner.

Connection type: rigid connection, non rigid connection

External encoders are not required (incremental or absolute)

Reference operation requires

Absolute encoder interface DIP11A is not required for absolute value encoders only

1.3 Function Description

Bus positioning achieves the following functions through fieldbus or system bus:

Any number of target positions can be defined and selected through PLC

The maximum stroke depends on the set stroke unit (1/10 mm → 3.27 m; mm → 32.7 m; cm → 327 m)

Support software limit switches

Support incremental or absolute value external encoders

Three operating modes: jog mode, reference mode, and automatic mode

Process data exchange (as shown in Figure 1):

Output data (PLC → frequency converter): control word (PO1), set speed (PO2), set position (PO3)

Input data (frequency converter → PLC): status word (PI1), actual speed (PI2), actual position (PI3)

1.4 Driving Scaling

The control system needs to know the number of encoder pulses (in inches/mm) corresponding to each stroke unit. The zoom function allows customization of user units (such as mm, m, cm, 1/10 mm, etc.).

No external encoder (rigid connection)

Automatically calculate scaling factor at startup

Required inputs: drive wheel diameter (or screw pitch), gearbox reduction ratio (i_gear), additional reduction ratio (i_additional)

Calculation formula: Number of pulses=4096 × i gauge × i additional, distance=π × diameter or pitch

Speed scaling: numerator (rpm) and denominator (mm/s, optional m/min or rpm)

There is an external encoder (non rigid connection)

External encoder activation and scaling must be completed in the Shell before starting bus positioning:

P941 "Source actual position" is set to EXT. ENCODER (X14) or APPROLUTE ENCODER (DIP)

Set P942~P944 encoder factors (numerator/denominator) and external encoder scaling

The automatic scaling function is blocked during startup

1.5 Limit switch, reference cam, and machine zero point

The software limit switch must be within the travel range of the hardware limit switch

The reference position and software limit switch must not overlap, otherwise fault F78 will occur

Reference offset: By setting the offset, the machine zero point can be changed without moving the reference cam. Formula: Machine zero point=reference position+reference offset

1.6 Process Data Allocation

Process output data (PO1~PO3):

PO1 control word 2: bit 0=reserved; Position 1=Enable/Quick Parking; Bit 2=Enable/Stop; Bit 3=Fault reset; Bit 4=reserved; Position 5=set position (automatic mode); Bit 6=fault reset (remains at 1 to remove limit); Bit 8=Start (Reference/Auto); Position 9=jog forward rotation; Bit 10=jog reversal; Position 11-12=mode selection (00=invalid, 01=jog, 10=reference, 11=automatic)

PO2: Set speed (user unit, such as mm/s)

PO3: Set position (user unit, such as mm)

Process input data (PI1~PI3):

PI1 status word: bit 0=ready to run; Bit 1=Enable; Bit 2=IPOS reference completed; Position 3=Target location reached; Bit 4=Warning; Position 5=Fault; Position 8=reference cam state; Position 9=positive limit switch; Position 10=negative limit switch; Position 11-12=mode status; Bit 13=jog forward activation; Bit 14=jog reversal activation

PI2: Actual speed

PI3: Actual location

Installation

2.1 Software Installation

Insert the MOVITOOLS CD, run setup, and follow the wizard to complete the installation.

Insert the bus positioning floppy disks (2 in total) and run setup to install the bus positioning program.

Start MOVITOOLS, select the correct COM port, and click<Update>to display the connected inverters.

2.2 MOVIDRIVE ®  Basic unit wiring

Regardless of the type of bus used, the basic unit must be wired according to the following diagram (Figure 11):

X13:1 (DI00)=Controller disabled (low level valid, set to 0 during debugging)

X13:2 (DI01)=Enable/Quick Stop (to be connected to+24V or controlled by PLC)

X13:3 (DI02)=Reset (controlled by PLC)

X13:4 (DI03)=Reference cam (connected to proximity switch or mechanical switch)

X13:5 (DI04)=positive limit switch

X13:6 (DI05)=Negative limit switch

X10:3 (DB00)=brake output (connected to brake relay)

2.3 Bus installation

For detailed installation instructions of each fieldbus option card, please refer to their respective documentation packages. The following is a summary of the key points.

2.3.1 PROFIBUS (DFP11A)

9-pin Sub-D socket, compliant with EN 50170 V2/DIN 19245 P3

Automatic baud rate detection (9.6 k~1.5 Mbaud)

Station address 0~125 (DIP switch setting)

GSD file: SEW-6000-GSD, DP identification number 6000hex

2.3.2 INTERBUS (DFI11A)

Remote bus input: 9-pin Sub-D plug; Output: 9-pin Sub-D socket

RS-485 transmission technology, 6-core shielded twisted pair cable

Module ID=227dec (E3hex)

2.3.3 CAN bus (DFC11A)

9-pin Sub-D plug, compliant with CiA standards

Baud rate optional (125/250/500/1000 kbaud, DIP switch)

Terminal resistance switchable (120 Ω)

ID range 3~1020, Base ID 0~63 (DIP switch)

2.3.4 DeviceNet (DFD11A)

5-pin Phoenix terminal, compliant with DeviceNet specifications

Baud rate 125/250/500 kbaud (DIP switch)

Address (MAC-ID) 0~63 (DIP switch)

Bus terminals require connectors with integrated terminal resistors (120 Ω)

Terminal colors: V - (black), CAN_L (blue), DRAIN (bare copper), CAN_S (white), V+(red)

2.3.5 System Bus SBus

Up to 64 sites, compliant with ISO 11898

2-core shielded twisted pair copper cable (0.75 mm ²/AWG18120 Ω @ 1MHz, capacitance ≤ 40 pF/m)

Maximum bus length: 250 kbaud → 160 m; 500 kbaud → 80 m; 1000 kbaud → 40 m

The terminal resistor (S12=ON) needs to be connected at the first and last stations, and the intermediate station should be turned off

All SBus connected devices must have potential equalization (with additional grounding wire)

2.4 Connecting limit switches

The limit switch cam must cover to the mechanical stop

Normally closed contacts (NC, low level effective) must be used

Connect DI04 (X13:5) to the positive limit, DI05 (X13:6) to the negative limit, and the common terminal to X13:9 (DGND) as shown in Figure 23

Start debugging

3.1 Preparation work

Check installation: encoder connection, fieldbus interface, limit switch wiring

Connect PC (RS-232, via USS21A option) and start MOVITOOLS

Use Shell to complete the basic startup of the inverter:

MDV60A+DT/DV/D motor → VFC-n-Control mode

MDV60A+CT/CV motor → CFC mode

MDS60A+DS/DY motor → SERVO mode

If using an external encoder (absolute value): Start the DIP11A interface first (set P942~P944)

If using incremental external encoders: manually set P942~P944 in Shell

Ensure X13:1 (DI00) is a "0" signal (controller disabled)

3.2 Start the "Bus Localization" program

In the Shell, select the menu Startup → bus positioning (Figure 24).

3.2.1 Setting fieldbus parameters (appearing during initial startup)

Fieldbus type: Select SBus/PROFIBUS/INTERBUS/CAN/DEVICENET

Address: Station address (consistent with the DIP switch settings on the bus option card)

Timeout time: Monitoring time (e.g. 500 ms)

Timeout response: timeout response (emergency stop/malfunction, etc.)

Baud rate: Baud rate (if the option card is set with DIP switch, this item will be grayed out)

3.2.2 Setting Zoom (Figure 26)

Source actual position：

No external encoder → Motor encoder (X15)

Incremental external encoder → EXT. ENCODER (X14)

Absolute value external encoder → APPROLUTE ENCODER (DIP)

When there is no external encoder:

Select "Drive wheel diameter" or "Screw pitch", enter the value (mm or 1/10 mm)

Input gearbox reduction ratio and additional reduction ratio

Click<Calculate>to automatically calculate the pulse/distance scaling factor (in inches/mm)

When there is an external encoder: the calculation function is blocked, and manual input of distance scaling factor and speed scaling factor is required (see online help example)

3.2.3 Setting Slope and Limit (Figure 27)

Software limit switch: Input the positions of positive and negative limits (in user units). If both are set to 0, the software limit will be disabled. It is necessary to ensure that the software limit is within the hardware limit travel and does not overlap with the reference position.

Reference offset: Set the offset of the machine zero point relative to the reference point.

Reference operation type (0-7):

Type 0: No reference operation, reference position is the zero pulse to the left of the current position

Type 1: Reference cam left edge

Type 2: Reference cam right edge

Type 3: Right limit switch (without reference to cam)

Type 4: Left limit switch (without reference to cam)

Type 5: No reference operation, reference position is the current position (no zero pulse)

Type 6: Reference cam left edge (similar to Type 1)

Type 7: Reference cam right edge (similar to Type 2)

Slope time: Acceleration and deceleration time in seconds for jog mode and automatic mode

Speed limit: maximum speed in automatic mode, maximum speed in jog mode, maximum speed in speed controller (P302). The latter two should be at least 10% smaller than P302

Click "Next>>" and save the settings. After the download window appears, click<Download>to write all parameters to the inverter and start the IPOS program.

After downloading, the program asks if to switch to the monitor (Figure 29). Select 'Yes' to enter the bus positioning monitor (Figure 30), where diagnosis and control can be performed.

3.3 Operation mode (selected through control word PO1 bit 11/12)

Mode bit 11 bit 12

Invalid 0 0

Jogging mode 1 0

Reference mode 0 1

Automatic mode 1 1

3.3.1 Reference Mode (Bit 11=0, Bit 12=1)

Premise: DI00=1, DI01=1, and PO1:1=1, PO1:2=1

Start the reference run with PO1:8=1 (keep it at 1 until complete)

The driver moves towards the reference cam at reference speed 1, switches to reference speed 2 when encountering the cam, and stops and locks its position when leaving the cam

When the status word PI1:2 (IPOS reference) is set to 1, PO1:8 can be revoked

After the reference is completed, it can be switched to automatic mode

3.3.2 Jogging mode (bit 11=1, bit 12=0)

Used for maintenance or manual adjustment

PO1: 9=1 → Forward turning jog; PO1:10=1 → Reverse jog

The jogging speed is determined by the set value of PO2

3.3.3 Automatic mode (bit 11=1, bit 12=1)

PO2 provides the set speed, PO3 provides the target position

PO1: 8=1 Start positioning (must remain at 1)

After reaching the target position, PI1:3 (Set position) is set to 1, and the driver position is locked

If PO1:8 remains at 1 and PLC updates PO3, the driver immediately moves to the new position

3.4 Parameter List

Automatically set the following parameters after startup (cannot be manually modified):

Parameter setting value description

P100 SBus/FILDBUS Setpoint Source

P101 SBus/FILDBUS control signal source

P302 0~5500 rpm Maximum speed 1

P600~P605 Enable/reset/reference cam/limit switches binary input function

P610~P617 IPOS input option card input

P630~P637 IPOS output option card output

P813 0~63 SBus address

P815 0.01~650 s SBus timeout

P816 125/250/500/1000 baud SBus baud rate

P819 0.01-650 s fieldbus timeout

P831 Programmable fieldbus timeout response

P836 Programmable SBus timeout response

P870~P875 IPOS PO/PI Data Process Data Description

P876 ON PO data enable

3.5 Remove the limit switch

When the drive collides with the limit switch (DI04 or DI05=0), PI1:5 (fault) is set to 1, and the drive comes to an emergency stop. Removal steps:

Set the operating mode to jog mode (PO1:11=1, PO1:12=0)

Set PO1:6 (fault reset) to 1, PI1:5 to 0

Maintain PO1:6=1, the driver automatically moves out in the opposite direction at a speed of 100 rpm

After removal, restore DI04/DI05 to 1, set PO1:6 to 0, and then switch back to the desired mode

Operation and maintenance

4.1 Fault Information

Fault memory P080 stores the last 5 faults (t-0 latest). When a fault occurs, the following data is stored: fault code, I/O status, operating status, inverter status, radiator temperature, speed, output current, active current, utilization rate, DC bus voltage, power hours, enable hours, parameter group, and motor utilization rate.

Shutdown response:

Immediately disconnect: output stage high resistance, brake immediately closes

Quick parking: Reduce speed according to the stopping slope t13/t23, and close the brake after reaching the stopping speed

Emergency stop: Reduce speed according to the emergency slope t14/t24, and close the brake after reaching the stopping speed

Reset method:

Power on again after power outage (main contactor disconnected for at least 10 seconds)

Through binary input DI02 (configured as reset function)

Reset button in MOVITOOLS Manager

Press the<E>key (P840) on the DBG11A keyboard

4.2 Specific fault codes

Possible causes and countermeasures for fault code name response

07 DC bus overvoltage immediately disconnected, deceleration time is too short, brake resistor open circuit extends slope, check brake resistor wiring

08 n - Immediately disconnect the overload, phase loss, and encoder wiring errors to reduce the load, and check the encoder A/A and B/B swapping

Immediately disconnect the encoder cable for poor shielding, disconnection, and short circuit in case of encoder malfunction. Check the continuity and wiring of the shielding layer

26 external terminal emergency stop programmable input received external fault troubleshooting fault source, reprogram terminal

27. The limit switch is missing. The emergency stop limit switch is disconnected or both are missing. Check the wiring and exchange the limit switch connections

28. If there is no master-slave communication during the fast parking monitoring time of the fieldbus timeout, check the communication of the master station, extend P819 or turn off the monitoring

When the limit switch reaches the emergency stop IPOS mode, the limit check travel range is reached, and the user program is corrected

31 TF sensor no response, motor overheating, TF not connected to cooling motor, check TF wiring, if not, short circuit X10:1-2

36. If there is no option, immediately disconnect the option card. If the type of the option card does not match or the encoder type is incorrect, use the correct option card and set it correctly to P100/P101/P700/P941

39. Immediately disconnect the reference cam without reference and check the wiring of the reference cam and limit switch for incorrect connections

Immediately disconnect the encoder due to 42 lag error, if the slope is too short or the position loop P is too small, check the encoder, extend the slope, and increase the P gain

47 system bus timeout fast stop SBus communication fault check SBus connection and terminal resistance

78 IPOS software limit unresponsive. Target position exceeds software limit range. Check user program and software limit position

92 DIP work area emergency stop absolute encoder exceeds allowable work area check position offset and zero offset parameters

93 DIP encoder malfunction, emergency stop encoder signal malfunction (such as power failure), check wiring cables, reduce maximum speed or acceleration

94 EEPROM checksum immediately disconnected, EMC interference or hardware defects returned to factory for repair

95 DIP rationality error, emergency stop encoder type error, zero position adjustment not reset to set correct encoder type, check IPOS travel parameters