AC Axial Flow Fans

MRS Series and Variable Speed MRS Series

AC Axial Flow Fans MRS Series and Variable Speed MRS Series
  • Large Size, Large Air Volume, High Static Pressure
  • The Speed of Three-Phase Fan Can be Changed via an Inverter
  • Includes Low-Speed Alarm
  • AC Input, Frame Size 140 to 250 mm

Features | AC axial flow fan MRS Series

Features

Features Large Air Flow

The MRS Series provides a large air flow and fast air circulation and is suitable for ventilation and cooling to cool the entire interior of the equipment.
When the ventilation resistance inside the equipment is large, it is better to use a large fan with large air flow and high static pressure to save energy and reduce wiring.

  • Cooling High-Density Packaging Equipment

    Cooling High-Density Packaging Equipment
  • Ventilation and Cooling of the Entire Interiors of the Control Cabinet and Equipment

    Ventilation and Cooling of the Entire Interiors of the Control Cabinet and Equipment

For Even Larger Ventilation Resistance

Centrifugal blowers as well as axial flow fans are suitable for allowing air to flow through equipment with large ventilation resistance, such as high-density equipment or narrow vents. The figure below shows a characteristics diagram comparing a centrifugal blower with a maximum air flow equivalent to that of the MRS Series □140 mm.
Centrifugal blowers are fans with high static pressure compared to axial flow fans.

Air Flow - Static Pressure Characteristics

  • Air flow - static pressure characteristics comparison
  • Fan comparison

    The actual air flow can be verified by the point of intersection of the characteristics line and the ventilation resistance line (operating point).

    [Air Flow Rate at 50 Hz Operation]

    • Axial flow fan 1.3 m3/min
    • Centrifugal blower 3.3 m3/min
      The centrifugal blower allows 2 m3/min more air to flow.
      When the ventilation resistance is large, consider a centrifugal blower.
  • The alarm output function is activated when the rotation speed drops below 70 % due to unexpected circumstances such as end of service life of the cooling fans or by the ingress of foreign particles, etc.
    This makes it possible to replace the fan before it comes to a complete stop.

    Low-Speed Alarm Function Equipped
  • Contact type fans with low-speed alarms have contact points that turn ON when rotation is normal, and can be connected in series as shown in the figure below.
    An alarm signal is output even if the number of rotations of one of the multiple units drops due to some kind of malfunction. At the same time, it can also detect abnormalities such as contact failure or disconnection on the alarm circuit.
    This can contribute to more reliable equipment design.

    Low-Speed Alarm Function Equipped

Speed Control Operation With Inverter and Variable Resistor

Noise Reduction, Power Saving and Even Longer Life, With Speed Control Operation

By adjusting the air flow according to the conditions, you can reduce noise and save power.
This also helps to reduce bearing deterioration and extend the life of the fan.

Advantages of variable speed fans

Click here for advantages of variable speed axial flow fans

Three-Phase Power Supply Input Products Can Adjust the Air Flow by Speed Control Operation Using an Inverte (Except for MRS14)

Three-Phase power supply input products can adjust the air flow by speed control operation using an inverter.
By using ceramic ball bearings, electric corrosion on the bearings due to noise can be prevented.

What is "electric corrosion"

When a fan is connected to an inverter or placed near equipment that generates high frequency signals, there is a possibility that electric current can flow within the bearing due to the influence of electromagnetic noise, leading to the occurrence of wave-like damage on the bearing surfaces.
This phenomenon is called 'electric corrosion' and it can be a cause of abnormal noise and reduced lifetime.

The three-phase 200V specification of the MRS Series* and MRE Series uses ceramic ball bearing in the bearing as a countermeasure against electric corrosion.
Ceramic ball bearing use ceramic as the material for the balls, which is an insulator, preventing the flow of current within the bearing and thereby preventing electric corrosion from occurring (Many fan ball bearings are made of metal).
We recommend using the MRS Series* or MRE Series as a countermeasure against electric corrosion not only when operating with speed control with an inverter but also when used near equipment that generates high frequency signals.

  • *Excluding MRS14
Ceramic Ball Bearing
Ceramic Ball Bearing

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Fan operation using an inverter

Air Flow - Static Pressure Characteristics (Characteristics of a single fan)

Example) When MRS18 is combined with an inverter (reference value)

Example) When MRS18 is combined with an inverter (reference value)
  • The value when a general inverter is used at factory settings.
    The characteristics vary depending on the type and settings of the inverter.
  • Use 60 Hz or less for the inverter's setting frequency and 240 V or less for the inverter's input voltage.
  • If an inverter is connected to an alarm type fan and the setting frequency is set to lower value, the rotation speed may be reduced and the alarm may be activated.
You Can See the Characteristics Data for Combinations With Inverters

Reference data for combinations with inverters from other manufacturers is made available to make it easy to connect to inverters.

[Reference Data]

  • Inverter parameter setting values
  • Air flow - static pressure characteristics and rotation speed/current/power consumption

Refer to the "Combining and Connecting With Products of Other Manufacturers" page

Variable Speed Type Fans Using Variable Resistors are Also Available (MRS16V-B)

Variable speed type fans using variable resistors (included) are available for 160 mm frame size.
It can be used without the need for an inverter.
Suitable for applications in which adjustment of the air flow is necessary, or applications in which a temporary decrease in noise is needed.

  • To Adjust the Speed Steplessly With a Variable Resistor (Included)

    Connect the included variable resistor to the lead wire coming out of the terminal box on the fan body.

    Adjust the speed using the variable resistor
  • To Adjust the Speed Step by Step With an External Fixed Resistor

    Switch over to the desired resistance with the fixed resistors (1/4 W min.) using a switch, relay, etc.

    Adjust the speed in stages using the external fixed resistors

Application Examples

Application Examples of the High Efficiency, High-Characteristics MRS Series

The MRS Series, with its large air flow and high static pressure, is suitable for cooling equipment that is crammed with devices inside with large air loss while air is flowing.

Example)
When cooling equipment with a board mounted with a heat generation of 120 W
Six MU1238 type units and one MRS16 type unit will provide approximately the same cooling effect.
Application examples for MRS Series

Energy Savings

With the MRS16 type fans, power consumption can be reduced by 60 %, reducing the running costs which include the electricity fees.

MRS16 MU1238
Fan Size □160 mm - 62 mm thick □119 mm - 38 mm thick
Number of Units 1 unit 6 units
Power Consumption 37.5 W 92.5 W
Annual Electricity Bill 6,750 JPY 16,206 JPY
Noise 49 dB 51 dB
  • *Electricity costs are converted at 20 JPY/kWh. When the fans are operating 24 hours a day, 365 days a year

Power consumption is reduced by 60 %

Simple Wiring

The MRS16 type fans can be used to reduce the amount of time and effort required to mount and wire the equipment.

MRS16 MU1238
Fan Size □160 mm - 62 mm thick □119 mm - 38 mm thick
Number of Units 1 unit 6 units
Number of Wires 3 12
Mounting Hole Processing
(Number of screws)
4 24
Temperature Rise Inside the Equipment
 
25 °C 25 °C
  • *For Single-Phase 100 VAC, 50 Hz

Reduces the time and effort required for machining mounting holes and wiring
 

Detects Failure and Low-Air Flow

The MRS16 type fans are available with a low-speed alarm so that they can be replaced before it causes damage to the equipment in the unlikely event of deterioration in air flow.

  • *The above is an example. Use Oriental Motor’s motor sizing service to find the best cooling fan for the mounting density and operating conditions.

Can be Used with the Accessory Sets

Easy Setup With the Finger Guard Set

Finger guards, mounting screws, and filters are included in the set of accessories necessary to use the fan.
Because these products are sets, there is no need to order individual components, and they can be assembled onto the fan immediately upon arrival.

  • *Finger guard set is sold separately.

Set Contents

  • Finger Guard Set (1 Guard)*1

    • Steel finger guard set
    • Stainless steel finger guard set
    Finger Guard Set (1 Guard)
  • Finger Guard Set (2 Guards)

    • Steel Finger Guard Set
    • Stainless Steel Finger Guard Set
    Finger Guard Set (2 Guards)
  • Finger Guard and Filter Set (1 Each)

    • Steel finger guard and filter set
    Finger Guard and Filter Set (1 Each)

Mounting Example

  • Mounting Example of Finger Guard Set (1 Guard)
    • Finger guards are used outside the control cabinet

      Outside →
      For preventing injury
  • Example Mounting of Finger Guard Set (2 Guards)
    • Finger guards are used on both the inside and outisde of the control cabinet

      Inside →
      For protection of the workers
      Outside →
      For preventing injury
  • Mounting Example of Finger Guard and Filter Set (1 Each)
    • Finger guards are used on the inside of the control cabinet, and filters are used on the outside

      Inside →
      For Protection of the Workers
      Outside →
      For protection against dust
*1
The variable speed type fans include 1 finger guard. Use in combination with the 1-guard set.

Click here for finger guard set

Product Line

MRS Series

Size Type and Alarm Product Line
□140 mm - 47 mm thick Non-alarm type
Low-speed alarm Electronic alarm type
□160 mm - 62 mm thick Non-alarm type
Low-speed alarm Contact alarm type During Normal Rotation: Contact ON
Normal Rotation: Contact OFF
Electronic alarm type
□180 mm - 90 mm thick* Non-alarm type
Low-speed alarm Contact alarm type During Normal Rotation: Contact ON
Electronic alarm type
□200 mm - 90 mm thick Non-alarm type
Low-speed alarm Contact alarm type During Normal Rotation: Contact ON
Electronic alarm type
□250 mm - 120 mm thick Non-alarm type
Low-speed alarm Contact alarm type During Normal Rotation: Contact ON
Electronic alarm type
  • The product with extension cable is scheduled to be discontinued.

Variable Speed MRS Series

Long life type AC axial flow fans are also available. Refer to the MRE Series.

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Narrow down Products

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