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Sensor for Iron & Steel IndustryMicrowave-guide type Detector

Microwave type not affected by vapor, disturbance light or smoke



-> This is a microwave detector. It consists of an antenna as detecting part and control unit composed of oscillator, wave detector and amplifier, and these two components are coupled together by a wave guide. Since the antenna is free from any electronic part which may be affected by heat, it can be used in high temperature environment without being cooled by water.
-> This device is suitable for using under bad environment because microwave isn't affected by vapor, disturbance light,smoke etc.
-> This device is reflective type. It is possible to detect small pipe, too.
-> This device provides monitor output that is monitoring oscillation of microwave.


Model No. Control unit: MBX-301CA
Antenna: MAR-201(Without air-purge), MAR-251(With air-purge)
Waveguide: MWG-20(Semi-seamless 2m), MWG-25(Seamless 2m), MFG-20(Flexible 0.5m)
Joint: MSJ-20(Socket), MBJ-25(Elbow), MCJ-20(Elbow with 45°)
Detectable objects Steel plate with reflection surface, 50×50mm or more
Detecting distance Approx. 300mm from antenna surface
Hysteresis 1mm to 30mm(Adjustable)
Microwave 10.525GHz ±15MHz
Allowable waveguide length 25m or less(Total of transmission and reception)
Air blowing of waveguide Air quality : Industrial clean air, Air amount : 20 lit/min., Air pressure : 980KPa(In case of MAR-251)
Power source 100 to 110VAC/200 to 220VAC(±10%, 50/60Hz)
Power consumption 4.5VA or less
Control output Contact : 1C relay contact(250VAC 3A, 30VDC 5A, cosφ=1)
Photo-coupler(75V 100mA)
Alarm output*1 1C relay Contact(250VAC 3A, 30VDC 5A, cosφ=1)
Response time Contact output : 10msec, photo-coupler output : 3msec
Connection M4 screw terminal, hub body with gland(Hole diameterφ18)
Display lamp Power lamp, operation lamp, alarm lamp, 5-step reception level lamp*2
Ambient temperature Control unit : -10 to +60°, Antenna/waveguide : -20 to +600°
Case Antenna : Bronze casting, Control unit : Aluminum die-casting
Weight Control unit : approx. 10kg, Antenna : approx. 11kg
*1 When oscillation of microwave is stopped by power failure or circuit trouble, this output is executed.
*2 Reception level is indicated with 5 steps.

External dimension


Note)Only MAR-251

Control unit

Control unit

I/O Circuit


Control output
Terminal No. 4-5 5-6 7-8
Power-OFF state CLOSE OPEN -
Power-ON state When non-detection OPEN CLOSE ON
When detection CLOSE OPEN OFF

Alarm output(monitor output)
Terminal No. 9-10 10-11
Power-OFF state CLOSE OPEN
Power-ON state When normal OPEN CLOSE
When troubled CLOSE OPEN

Characteristics Data

Detecting characteristics

Detecting characteristics


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