FAQ Motor

You can roughly calculate the input wattage. Calculates the amount of wattage per phase from the resistance value of a coil and the rated voltage. Then multiplies the wattage by two (for a 2-phase motor).

Ex.: PF25-48Q1 motor; coil resistance: 15 Ω, rated voltage: 4.4 V, so 4.4 ^ 2 / 15 = 1.29 W / phase. Therefore, the input wattage is approx. 2.6 W.
The above calculation is for when the motor is stopped (0 pps), so the wattage can increase or decrease during rotation depending on the excitation method or the pulse rate.

Please specify with a capacitor when ordering.

Depending on the drive system and motor size, it is generally expected to occur at around 100 pps.
When considering not only resonance but also turbulence, the drive frequency area up to about 200 pps requires attention.

Most HB-type stepping motors are coiled with the assumption of constant current drive, so we recommend to drive the motor by 0.95 A constant current drive.

In the constant current drive circuit, 24 V is turned ON and OFF at high speed by chopping operation so that the current of 0.95 A flows to the coil. In this case, that is the equivalent to a voltage of 2.66 V (effective value) being applied.
*Actually, it varies depending on the load and speed.

Yes. The length of lead wires should be 50 mm or longer up to 500 mm as a guideline.
Please contact NPM for details.

You can perform the continuous rotation if the motor is driven at the rated voltage and rated current or less.

Also, you can drive at very low speed. For the pulse width, refer to the manual of the drive circuit.

There is no particular limitation. However, if you drive a motor at low speed, resonance and disturbance tend to occur as well as vibration increases. Therefore, it may be better to review the driving conditions, excitation method, etc.

Although it is calculated to be 10 times greater, the torque will be actually less than 10 times due to the gearhead efficiency.

A possible measure includes attaching a commercially available spark killer.

Since the rotational speed of a synchronous motor depends on the frequency, you cannot change the speed.
The motor is suitable for applications requiring accurate constant speed.

A guideline is 3,000 hours without load, but there is no clear standard because it varies greatly depending on the load or ambient temperature.

There is no problem in the usage of a stepping motor, but be careful of not to cause out-of-step due to the decrease in torque when accelerating, and be careful of disturbance and resonance when decelerating.

When using a stepping motor with a gearhead, rapid reversal may affect the gearhead life due to the inertial load.

If a load exceeding the holding torque is applied when excited and stopped, the motor will be out-of-step. However, it does not cause a problem.
In non-excited state, cogging (detent torque) occurs, and you feel a crunchy resistance.

Please confirm that you will not be affected by the generated vibration nor the back electromotive force (generation).

For geared stepping motors, do not apply any external force.

It is available by customization. Please contact us.

Depending on a shaft diameter, we may be able to offer.

The rated voltage is a voltage that can be used to operate continuously. So, even 12 V can be used for a short period of time as long as the motor case temperature remains at 100°C or less.

Motor products are guaranteed for one year. However, a motor life cannot be specified quantitatively because it fluctuates greatly depending on the ambient temperature, rotational speed, and load.
If durability is required, it is necessary to evaluate the actual device. Please contact us for more information.

Stepping motors have relatively longer life and higher durability than brush motors because there are no wearing parts other than bearings.

The angle error indicates an error per one step (5% = 0.375° of 7.5° per step as an example), and it does not accumulate.

For example, the angle error at the point of 90° (12 steps) rotation will be 90° ± 0.375°.
Of course, even if the motor rotates 10 times (3,600°) or 20 times (7,200°), the angle error will be ±0.375°.

Unfortunately, stepping motors are not suitable for power applications such as driving fans because they are suitable for positioning applications.

Even with micro-step drive, the maximum rotational speed is not changed from the full-step drive basically, but the speed may drop slightly due to the difference in the excitation method.

To achieve the same rotational speed in 1/16 micro-steps as the full-step, enter 1000 × 16 = 16000 PPS .
(Pay attention to the maximum input pulse rate to the driver.)

It specifies the backlash at the output shaft.
The actual value is a little better, but it indicates the guaranteed value.

Stepping motors can generate electromotive force by rotating the shafts, but they are inferior to dedicated generators in terms of efficiency and capacity.

As a guideline for high temperatures, if the case temperature is 100 °C or less during motor operation, the coil temperature is considered to be 120 °C or less, so there is no problem. (excluding neodymium magnet specifications)

If the temperature exceeds 100°C, it is necessary to take measures such as separating from the heat source or using air-cooling.

No, but synchronous motors with bi-directional rotation can be the equivalent, which can start and stop instantaneously.

A synchronous motor rotates in synchronization with power frequency. So the motor torque decreases if the voltage is reduced, but the rotation speed does not change.

If the torque decreases, the motor can go out-of-step (or stop) when the load increases. Thus it will not maintain the correct rotation speed.

Please use stepping motors for applications where you want to change the rotational speed.

Please consider the brake options available in the PULSERVO series.

The operating temperature range is up to +50 °C for products listed in our catalog. However, as long as the case surface temperature is 100 °C or less, the products may be used under conditions (motor temperature rise 30K or less).


Customization is also available. Pleaes contact us for more information.

With a PF25-24 motor, 2000 rpm is 800 pps. According to the characteristics chart, the motor should be able to rotate by constant current drive.

Please contact us for more information on torque characteristics at 2000 rpm.

A synchronous motor with a gearhead can be used.
For example, the PTM-24AG series.

The rated input power we specify for this model is 0.36 W.
At 10V, it becomes 5W. So the coil can burn out in a short time.

Please conduct the test by increasing the voltage gradually while checking the motor surface temperature so that it does not exceed 100°C.

The coil specification of a PFCU20-40S4GA2 motor is designed for the constant-voltage drive, so there is a possibility that the motor characteristics may not be fully utilized.

PFCU20-40W4GA2 (40Ω, 5.5V rated voltage ) motor is recommended for the constant-current drive.

We have coil specifications such as 50 Ω and 65 Ω, which are close to 60 Ω. Pleae contact us for more information

Unfortunately, we do not.

There are no clearly defined compatible products. However, there are examples of applications in which the customer is responsible for the use of the product.
Please contact us for details.

The breaking gear strength is a value that may cause chipping or breakage of the gear.

Normal gear strength is a reference value for continuous operation.

Normally, please use with the value (load) equal to or lower than the normal gear strength.

Only 250 (300) RPM and 500 (600) RPM are available in our synchronous motors. (Figures in parentheses are for 60Hz)

The cataloged products use (iron-based) sintered sliding bearings, but the bearing specifications can be customized. Please contact us.

We offer PULSERVO series with built-in encoder and closed-loop control enabled.

Some models may be compatible.
Please note that there may be restrictions by laws and regulations. Please confirm the details in the specification sheet.

You can drive a motor continuously as long as the motor is driven within the operating temperature range and below the rated voltage.

Also, it is possible even under other conditions if the motor heat generation does not exceed 100 °C on the case surface (excluding neodymium magnet motors).

PF35T is a thinner type than PF35. (The characteristics are also different. Please check the specifications for official information.)

Both H and M gears can be combined with 35 mm size motors, but there are differences in gear ratio, gear strength, etc. besides the external dimensions.

Unfortunately, the reduction ratio is difficult to design, so they are not in our lineup.

They are designed to be nearly the same.