The failure to start the Roots blower is a common fault that may be caused by electrical, mechanical, or operational issues. The following are systematic troubleshooting and solutions:
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**1、 Electrical system issues**
1. * * Power failure**
-Performance: The motor has no response and the indicator light is not on
-* * Reason * *:
-Power interruption (circuit breaker tripping, fuse blown)
-Voltage too low (below rated voltage by 10)
-Cable breakage or poor contact
-* * Resolve * *:
-Check the circuit breaker/fuse of the distribution box, reset or replace it
-Measure voltage (multimeter detects three-phase 380V ± 10)
-Tighten the cable joints and inspect the wiring
2. * * Motor malfunction**
-Performance: The motor buzzes but does not rotate
-* * Reason * *:
-Motor phase loss (single-phase operation)
-Winding burnout or bearing jamming
-* * Resolve * *:
-Use a clamp ammeter to check if the three-phase current is balanced
-Manually rotate the motor shaft. If it gets stuck, replace the bearing or motor
3. * * Control circuit issues**
-Performance: No signal from the control panel
-* * Reason * *:
-Thermal relay/overload protection triggered
-PLC or contactor contact oxidation
-* * Resolve * *:
-Reset the thermal relay and check if the set value matches the motor power
-Clean the contactor contacts or replace components
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**2、 Mechanical system issues**
1. * * Rotor stuck**
-* * Performance * *: Unable to turn manually
-* * Reason * *:
-Insufficient clearance between impellers leads to friction
-Foreign objects entering the cavity (such as bolts, welding slag)
-Bearing fracture and locking
-* * Resolve * *:
-Disassemble and inspect the fan for foreign objects
-Adjust the impeller clearance to 0.2~0.4mm
-Replace bearings (note model: such as SKF 6311)
2. * * Transmission component malfunction**
-Performance: Belt slippage or abnormal coupling noise
-* * Reason * *:
-Belt breakage/looseness (belt drive type)
-Coupling alignment deviation>0.1mm
-* * Resolve * *:
-Replace the belt and adjust the tension (press down by 5-10mm)
-Re calibrate the concentricity of the coupling (laser alignment instrument)
---
**3、 Operation and system issues**
1. * * Start without pressure relief**
-* * Performance * *: Instantaneous surge in current during startup and tripping
-* * Reason * *:
-The outlet valve is not open or the pipeline is under pressure
-* * Resolve * *:
-Fully open the outlet valve first, release pressure before starting
2. * * Media issues**
-Performance: Overloading of the motor due to excessive load
-* * Reason * *:
-High gas density during transportation (such as gas not being replaced)
-Imported filter clogged
-* * Resolve * *:
-Replace pipeline gas to air state
-Clean or replace the filter
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**4、 Quick troubleshooting process**
```mermaid
graph TD
A [Fan not starting] -->B {Power supply normal}
B -->| Yes | C [Manual turning]
B -->| No | D [Check circuit breaker/cable]
C -->| Cannot rotate | E [Disassemble and inspect mechanical components]
C -->| Rotatable | F [Check motor and control circuit]
E -->G [foreign object/adjustment gap]
F -->H [detecting voltage/contactor]
```
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**5、 Preventive measures**
1. * * Pre startup check * *:
-Confirm valve status (inlet fully open, outlet slightly open start)
-Manual turning for 2-3 turns to confirm no jamming
2. * * Regular maintenance * *:
-Monthly inspection of belts/couplings
-Lubricate bearings quarterly
3. * * Install protective devices * *:
-Install pressure switch and overload alarm
---
**6、 Special case**
-Inverter controlled fan:
-Parameter setting error (such as too short acceleration time) → Adjust to 10-15 seconds
-Explosion proof environment:
-Poor sealing of explosion-proof motor junction box → Re package according to Exd standard
**Tip: If self inspection fails, please contact the manufacturer to provide a circuit diagram or on-site support to avoid blind disassembly and secondary damage!
