01
Detect falling speed before throughput collapses
Useful on conveyors, fans, screw conveyors and bucket elevators where loss of speed indicates slip, overload or failure.
ifm · Motion Control
ifm Speed Sensors & Compact Speed Monitors
Monitor rotational speed, underspeed, overspeed, blockage and standstill directly at the machine. ifm compact speed monitors combine target detection and evaluation in one sensor housing, reducing the need for separate pulse evaluation in the PLC.
Inductive / magneticStandstillUnderspeed / overspeedIO-LinkM12 / M18 / M30 / cube
Architecture2-in-1Sensor + speed evaluation
Sensor principleInductive / magneticDepends on product route
IO-Link rangeUp to 24,000pulses/min on selected M12/M18 variants
Start-up delayConfigurableHelps suppress false alarms during machine start
Machine protection
Detect a drive that is too slow, too fast or no longer moving
The compact monitor evaluates target pulses locally and can switch an output when the configured speed condition is reached.
02
Recognise a stopped shaft or mechanism
Local evaluation can provide a simple machine-running / machine-stopped signal without PLC frequency calculations.
03
Detect a speed above the configured limit
Use on suitable machine functions where an overspeed alarm or interlock is required.
04
Identify abnormal conveyor motion
Target-pulse monitoring can reveal torn belts, blocked screws or stalled rotating equipment.
Typical applications
Speed monitoring is strongest where a simple local condition must be available immediately
01
Conveyors and bucket elevators
Monitor shaft rotation to detect underspeed, standstill or belt-related failure conditions.
02
Exhaust and process fans
A remote fan can be monitored for falling speed or standstill to trigger maintenance or an alarm.
03
Speed pickup and machine motion
Compact housings support speed pickup and local evaluation where space and wiring are limited.
Operating principle
The sensor measures the time between passing targets and evaluates speed locally
The inductive or magnetic sensing head detects a metallic or magnetic target on the rotating part. The electronics convert the pulse timing into rotational speed and compare it with configured limits.
Target detectionA cam, bolt, target wheel or other suitable damping target passes the sensor face.
Speed calculationThe time between target events is converted into rotational speed.
Limit logicSingle, two-point or window behaviour is available on current IO-Link routes.
Start-up behaviourConfigurable start-up delay prevents nuisance alarms while the machine accelerates.
Current compact monitor range
Select by housing, mounting and required pulse range
The DI50xx IO-Link compact monitors provide several mechanical formats. Verify sensing distance, flush/non-flush mounting and target arrangement for the actual machine.
| Models | Housing | Mounting | Setting range | Best-fit consideration |
|---|---|---|---|---|
| DI5027 / DI5028 | M12 | Flush / non-flush | 5…24,000 pulses/min | Small housing, high pulse rate |
| DI5029 / DI5030 | M18 | Flush / non-flush | 5…24,000 pulses/min | More sensing distance than M12 |
| DI5031 / DI5032 | M30 | Flush / non-flush | 5…14,400 pulses/min | Larger sensing face and working distance |
| DI5033 / DI5034 | Rectangular / cube | Flush / non-flush | 5…9,600 pulses/min | Alternative mounting geometry |
Selection criteria
The target geometry matters as much as the sensor model
Representative DI5028 data
Use the family matrix for routing, then validate exact sensing distance, output configuration, environment and speed range on the selected order number.
Representative modelDI5028
Sensor principleInductive
HousingM12 × 1, L = 60 mm
Setting range5…24,000 pulses/min
Start-up delay0…30 s configurable
CommunicationIO-Link
Not a functional-safety speed monitor. A standard ifm compact speed sensor can monitor machine condition and process speed, but it should not be presented as a safety-rated safe-speed or safe-standstill function unless a specifically safety-certified architecture is used.
Requirement capture
Inputs required to select the speed monitor
Rotating elementShaft, fan, conveyor, sprocket, wheel or linear moving target.
Normal speedRPM or pulses/min during normal operation.
Fault conditionStandstill, underspeed, overspeed, blockage or belt failure.
Target arrangementNumber of targets per revolution, material and available sensing gap.
Mounting spaceM12, M18, M30 or rectangular geometry.
Control interfaceSwitching output, IO-Link parameters and PLC architecture.