How Does Belt Width Monitoring Detect Conveyor Belt Rips?
Quick Answer
The BG5k detects longitudinal rips by continuously monitoring the width of the belt using two non-contact ultrasonic sensors positioned at the belt edges. When a rip causes the torn sections to separate (widening), fold over (narrowing), or drop into the trough, the resulting dimensional change triggers an automated conveyor stop. The system does not detect the rip directly — it detects the consequence of the rip: a change in belt width.
Key Definitions
Belt width deviation: A measured change in the distance between belt edges, outside the operator-configured tolerance window.
Fail delay timer: A configurable time period that the deviation must persist before the Halt signal is issued, filtering out transient width changes from poor belt edge condition.
How It Works
Two ultrasonic sensors are mounted on the conveyor structure, one measuring each belt edge position. They are installed 10–20 metres after each load point in the carry path. The sensors continuously measure the position of each belt edge and calculate belt width in real time.
An operator-set tolerance window defines the acceptable belt width range. Normal sideways belt movement (tracking/wander) does not cause a rip signal because the belt width remains constant even as it moves laterally. When a rip causes the belt to widen, narrow, or fold, the measured width deviates beyond the tolerance window. If the deviation persists beyond the Fail Delay timer, a Halt signal is sent to the PLC.
What It Also Provides
In addition to rip detection, the BG5k provides continuous belt tracking data in millimetres via Modbus TCP/IP or 4–20mA output. This tracking data is valuable for early detection of belt mistracking, which can cause edge damage and accelerated wear if left uncorrected.
System Limitations
Critical limitation: The BG5k requires a measurable change in belt width following a rip event. On thicker, laterally stiff steel cord belting, the torn sections may not separate or fold sufficiently to produce a width change. If no width change occurs, the device will not stop the conveyor. This is documented in the operator manual and should be a factor in system selection for steel cord applications.
- The sensors are self-cleaning when powered, but may require manual cleaning (hose down or alcohol wipe) if blocked by debris
- If a sensor becomes blocked, the device reports an unhealthy state and de-energises the Healthy relay
- Works on fabric, PVC, and steel cord belting
Field Example
The BG5k is widely deployed at coal handling plants, grain terminals, and fabric belt operations where sensor loop systems cannot be used. Multiple units can be installed along a single conveyor — one after each load point — to minimise potential rip length by detecting events as close to the initiation point as possible.
Common Questions
Q: Will the BG5k detect every rip?
No. It will only detect rips that produce a measurable change in belt width. On stiff steel cord belts, this change may not always occur.
Q: Does it work on fabric belts?
Yes. The BG5k works on fabric, PVC, and steel cord belting — it is belt-type agnostic.
Q: Does belt wander cause false alarms?
No. Normal sideways belt movement does not change belt width, so it does not trigger a rip signal.
Learn more about the BG5k.