Micro Direct Drive Motor FAQ
About DD Motors
What type of motor is a μDD Motor?
It is an AC servo motor. The driver power supply voltage is DC, but internally it uses a three-phase PM rotor. It supports smooth position and speed control from ultra-low speed to high speed, as well as high-precision current control.
Why can μDD Motors achieve high-precision positioning?
High-precision positioning is possible thanks to a core with finely divided slots and a high-resolution encoder.
One of the features of equipment using μDD Motors is quiet operation. Why are they quiet?
Because of the gearless structure, there is no gear friction noise or sliding noise, which results in excellent quietness.
Is it okay to apply the load directly to the shaft?
Yes. High-rigidity bearings are used, so applying a load directly to the shaft is not a problem as long as it is within the allowable load range.
We are considering reciprocating motion at very small angles. Are there any concerns?
Reciprocating motion at very small angles is not recommended because it shortens bearing life. Periodic full rotation can help reduce the drop in service life.
We are considering vertical use. Are there any concerns?
Because of its high backdrivability, it is not suitable for holding in the vertical direction. For safety, we recommend using it together with a brake or a reducer.
We are using a hollow-shaft type motor, and there is a step partway inside the hollow bore. Is this a defective product?
No. This step is caused by the machining process and is not a defect. Please use a shaft with a diameter smaller than the drawing specification for insertion.
Is the encoder incremental or absolute?
Both types are available. A model number ending in “E” indicates incremental, and “B” indicates absolute.
How accurate is the rotating shaft?
Face runout and shaft runout are both 20 to 30 μm. A high-precision machining option is also being prepared.
Is it possible to add positioning pins to the rotating shaft as a custom option?
Yes. Please let us know your required layout and size.
If the resolution is reduced, how much can the rotational speed be increased?
It depends on the series. For example, the MD-20 can run at about 4000 rpm. Please contact us for details.
Do you have a μDD Motor with a reducer?
Sample loans and sales are available. Please contact us for details.
If a 48 V motor is driven by the MC-200 using a 24 V power supply, what happens to the motor specifications?
Peak torque and continuous torque will both be reduced by about 70%. We recommend using 48 V.
If the MDH-6018 is driven using a 24 V power supply, what happens to the motor specifications?
The peak current is about 7 A instantaneous, and the rated current is 3.2 Arms, so a power consumption capacity of at least 168 W is required.
Please tell me how to deal with noise.
Measures such as proper FG wire connection and avoiding ground loops are required. Please refer to the drawings and support documents for details.
About Servo Drivers
How much power supply capacity is required?
Please select the power supply based on motor rated current × supply voltage. We recommend allowing some margin depending on the load conditions.
How should the upper-level controller for the driver be selected?
Pulse commands from the I/O port, analog current commands, and USB or SPI communication can be used. Please select according to your system requirements.
Please tell me the pin assignment of the CN1 power connector.
The role of each pin is shown in the drawing. Please contact us if you need the specification sheet.
Is it possible to obtain encoder signals? The encoder mounted on the motor is incremental.
Yes. ABZ phase signals can be obtained through USB or from the CN4 output.
Please tell me about the position information output from the driver when an absolute-type motor is connected to the MC-200-7220A.
ASCII or binary format is output as RS422 differential signals from CN4 pins 27 and 28.
What is the current consumption of a μDD Motor + MC-200 combination?
It is 150 to 250 mA when the servo is OFF. When the servo is ON, add the drive current.
How much current is consumed by the interface power supply on CN4 of the MC-200-7220A?
About 50 to 100 mA.
If I want to give an emergency stop signal from the upper-level controller to the driver, which input is recommended?
It is recommended to assign emergency stop or deceleration stop to DIN and use that input.
I want to move the motor manually while the servo is OFF. In that case, can the encoder read the manually rotated amount and display the travel amount on a PC?
Yes. The driver can output encoder values.
Are there any points to note regarding the installation environment of the driver inside a control panel?
Please avoid temperature rise and install a cooling fan. It is recommended to install the unit with CN1 facing downward.
How can the force applied to the motor be measured?
It can be calculated from effective current × torque constant. The value can be obtained through USB or CN4.
Please tell me the homing procedure.
By using the Z phase, setting DIN to HOME, and inputting pulses, homing can be performed.
I would like to know the detailed electrical specifications of CN4 on the MC-200C.
They are listed on page 16 of the specification sheet. Each pin is 5 V CMOS.
Is the command input on CN4 sink input or source input? Also, what voltage signal should be applied?
From the external device side, it is sink input. Please use it within the VCC 5 to 24 V range.
About Driver Specifications
Is it possible to command position or speed using USB communication?
Yes. Command control is possible via USB.
Is it possible to obtain motor current values using USB communication?
Yes. They can be obtained with the $Ecur or $G command.
I am using the MC-200-7220A. Please tell me the settings when giving commands from an upper-level PLC, position control.
Set parameter #100 to 30 and #101 to 1, then save the settings and turn the power back on to activate them.
I am using the MC-200-7220A. Please tell me the pulse input method for position commands from an upper-level PLC.
Set parameter #300 to one of the following: PLS/DIR, CW/CCW, or 2-phase 90° phase difference.
What is the maximum pulse frequency that can be input to the MC-200-7220A?
Single phase, 2.5 MHz.
The firmware update failed.
Please refer to the firmware update document. Click here for the document
7-segment display “2” blinking, an encoder error alarm occurs.
The encoder wiring may be disconnected. Please inspect the wiring.
7-segment display “5” blinking, when servo ON, an overspeed alarm occurs.
The initial encoder resolution setting may be different. Please check the model setting in MTLParam.
7-segment display “6” blinking, an overcurrent alarm occurs.
The load or motion is too large. Please review the load conditions and mounting accuracy.
7-segment display “7” blinking, a position deviation excess alarm occurs.
Please check the value of parameter No. 406 and the gain settings.
7-segment display “A” blinking, a low-voltage alarm occurs.
There is a high possibility that the power supply capacity is insufficient. Please check the capacity.
7-segment display “D” blinking, an electronic thermal alarm occurs.
The driver output current exceeds the set value. Please review the duty cycle and cooling environment, and contact us if necessary.
7-segment display “3”, counter overflow occurs.
The count value exceeds the 32-bit range. It can be recovered by resetting the counter.
About the Dedicated Software “MTLParam”
The COM port is not recognized.
The supported OS is Windows 10. Please try changing the COM port number and baud rate, and also check the USB cable length.
How should I install the USB driver?
Please install the FTDI VCP driver. If you cannot access it, please contact us.
What does “K” mean in the motor model number?
It means 1000. For example, 108KE means 108,000 pulses.
Should the encoder value entered on the MODEL setting screen be the value after x4 multiplication?
No. Enter the resolution before x4 multiplication. Example: 108,000 pulses.
Please tell me the recommended waveform sampling time for the graph.
50 to 100 ms is recommended. Please close unnecessary items while using it.
I would like to adjust the gain of the current control loop. Is there a recommended method?
Please use the analog monitor on CN4 to check the effective current value, and then adjust the proportional gain and integral gain.
Even though CONTROL shows servo ON, the motor does not move when I press the HOME button or POSITION button. What could be the problem?
Please check whether internal command and position control are set correctly, and recheck the MODEL settings.
About Purchasing
What is the minimum order quantity and lead time?
We can sell from one unit.
Since these are made-to-order products, it usually takes about 2 months after receiving the order, but some items may be in stock, so please contact us.
Please tell me how to purchase.
There are two ways to purchase a μDD Motor.
1. Post-payment: First, please send a quotation request by email through the inquiry form. Our sales representative will get back to you.
2. Through a distributor: Distributors vary by region. We can also provide support through them.
Please contact us through the inquiry form for details.
Support and Demos
Do you have loan units?
Yes, we have loan units available. For some models, production may be required, so please consult with us in advance. The loan period is up to 3 weeks.
I would like to obtain a product specification sheet or instruction manual.
We have specification sheets prepared for each model. Please request them through the inquiry form.
I would like to export equipment incorporating a μDD Motor overseas. Can you issue a non-applicability certificate?
A non-applicability certificate is required for overseas export. It takes about 1 week to issue, so please request it with enough lead time.
Do you have CE-mark compliant products?
All μDD Motor models are CE-mark compliant. A Declaration of Conformity can be issued, so please contact us if needed.
I would like to see an actual μDD Motor in operation. Is a live demonstration possible?
Yes. Live demonstrations are available in our showroom. We can also provide on-site demonstrations using a portable demo unit.
Can you provide local support overseas?
We do not provide on-site support overseas, but if you send the product itself to us, we can analyze it. If you plan to export the product, please contact us in advance.
About Collaboration with Other Manufacturers
Mitsubishi Electric J4 Series
Can it be connected to a Mitsubishi Electric J4 amplifier?
Yes. Please refer to the collaboration catalog.
Can it be connected to AC200V “MR-J4-〇〇A” and “MR-J4-〇〇B” models?
Yes, connection is possible. However, the MD20 series is not supported.
Can my current “MR-J4-〇〇A” or “MR-J4-〇〇B” be connected to a μDD Motor?
No. A dedicated amplifier is required.
Can a CC-Link IE compatible amplifier be connected to a μDD Motor?
No. Only SSC-NETⅢ compatible amplifiers can be used for this collaboration.
Can I purchase the connector cable for connecting a μDD Motor and a J4 amplifier?
Yes. We offer conversion connector cables.
Do you have a product specification sheet for the J4 amplifier for collaboration use?
Yes. Please contact your distributor or us.
Where can I obtain the motor parameter setting file, mmd file, for AC200V collaboration amplifiers “MR-J4-〇〇A-J001” and “MR-J4-〇〇B-J001”?
Please contact us.
We will provide it directly.
How should I purchase the motor and amplifier?
Please follow the normal sales route. Contact us for the motor, and the distributor for the amplifier.
What should I do in the event of trouble?
Please carry out the initial diagnosis. If the problem is on the motor side, contact us. If it is on the amplifier side, contact the amplifier manufacturer.
Is it possible to use a smaller amplifier capacity?
Yes, but the output characteristics will change, so please consult with us in advance.
Is there a recommended inertia ratio?
Basically, 50 times is the guideline. More than that may also be possible with proper tuning.
Panasonic
Can it be connected to a Panasonic amplifier?
Yes. Please refer to the collaboration catalog.
Can it be connected to the AC200V “A6L”?
Yes, connection is possible. However, the MD13 and MD20 series are not supported.
Can I connect the MINAS amplifier I am currently using to a μDD Motor?
It depends on the amplifier model. Please contact us for details.
Can I purchase the connector cable for connecting a μDD Motor and a MINAS amplifier?
Yes. Conversion connector cables are available.
Can it be connected to a μDD Motor with an absolute encoder?
Yes. The MFC-10P conversion board box is required.
Can an EtherCAT compatible amplifier be connected to a μDD Motor?
Yes, connection is possible with the A6BL.
How should I purchase the motor and amplifier?
Please follow the normal sales route and contact either us or your distributor.
What should I do in the event of trouble?
Please carry out the initial diagnosis. If the cause is on the motor side, contact us. If the cause is on the amplifier side, contact the amplifier manufacturer.
About Customization
I would like to request customization. Is that possible?
Please contact us with your required specifications. We will review whether the request can be supported. If possible, we will proceed with the production cost, lead time, and specification agreement.
Main customization examples:
■ Encoder resolution changes
■ Tapping inside the hollow shaft
■ Low particle generation specifications
■ Enlarged hollow shaft bore
■ Cable length and connector changes
■ Flangeless motor case structure
■ Output shaft structure changes, such as pinion gear, additional positioning pins, knurling, aluminum anodizing, and more
Customization Examples Page
Do you have a μDD Motor with a brake?
Not at this time. It is currently under development. Please contact us for details.
About Master-Slave Control
What is master-slave control?
It is a system that is ideal for remote operation. Please see the page below for details.
What Is Master-Slave Control?
