Embed Size (px)
Citation preview
LAST UPDATED: 02/11/2020
Proximity Sensor - Troubleshooting Guide
Introduction
The image shows the various types of proximitysensors used on Haas machines.
Proximity Sensor - Troubleshooting Guide
Page 1 of 5 pages
Symptom Table
SYMPTOM POSSIBLE CAUSE CORRECTIVE ACTION
Noise or electricalinterference from high-powercables.
Re-route the cable away from high power sources. Apply aferrite bead to the sensor cables at the I/O board.
Positioning error ortimeout alarms.
The diagnostic bitfluctuates while themonitoredcomponents areidle.
There is a poor connection, ora signal interference fromcontamination.
Clean, reseat connectors, and correct the cause ofcontamination.
There is metal particles on theface of the sensor.
Metal particles will not let the switch change state. Clean metalparticles from the face of the proximity sensor.
The sense gap between thesensor face and the trip flag isnot correct.
Align the trip flag or sensor, make sure the gap between theface of the sensor and the trip flag does not exceed 0.126inces.
The diagnostic bitdoes not changestate.
The cables or the I/O PCB is atfault. Troubleshoot the cables or the I/O PCB.
There is metal particles on theface of the proximity sensor.
Metal particles will not allow the sensor to change state. Cleanmetal particles from the face of the proximity sensor.
The proximity sensorconnector has a looseconnection.
Check the proximity M12 connector make sure the connectionis tight.
The cable from the control tothe proximity sensor has anopen connection.
Check the proximity sensor and extenstion cables for damage.
Alarm 145-147 AXISLIMIT SWITCHalarms.
The sense gap between thesensor face and the trip flag isnot correct.
Align the trip flag or sensor, make sure the gap between theface of the sensor and the trip flag does not exceed 0.126inces.
Alarm 103-105 AXISSERVO ERROR TOOLARGE alarms.
There is metal particles on theface of the proximity sensor.
Metal particles will not allow the sensor to change state. Thiswill cause the axis to home in the opposite direction, causingthe axis to hit the hard stop. Clean metal particles from theface of the proximity sensor.
Alarm 165-167 AXISZERO RETURNMARGIN IS TOOSMALL
False sensor trip due to chipor home sensor problem, orthe axis grid offset parameteris not set properly
Check for metal chips around the sensor or trip flag. Check thesensor for damaged cables. Set the axis grid offset parameter.
Proximity Sensor - Troubleshooting Guide
Page 2 of 5 pages
Signal Noise / Signal Interference
Cable Damage
Make sure that the proximity sensor cable is notdamaged, and that it is separated from high-power spindle/axis/pump cables.
Make sure that the connectors and pins for theproximity sensors are not contaminated. Makesure the pins have not backed out of theconnector.
Check for contamination on the proximity sensor.Contamination on the face of the proximitysensor can create a false signal. Fix the cause ofthe contamination.
Put a screw in front of the face of the sensor totest its operation. If the proximity sensor LEDturns on and off, and the diagnostic bit changesstatus, then the sensor is working correctly. Alignthe trip flag so that it triggers the proximitysensor.
Check the proximity sensor and extenstion cablesfor damage.
If there is no damage to the cables, refer to:
• NEXT GENERATION CONTROL - I/O PCB- TROUBLESHOOTING GUIDE
• CLASSIC HAAS CONTROL - I/O PCB -TROUBLESHOOTING GUIDE
Proximity Sensor - Troubleshooting Guide
Page 3 of 5 pages
Malfunctioning Proximity Sensor
N.O. 2 Wire 12V Proximity Sensor: (Black lead to ground and red lead to the brown wire)
Proximity Sensor State LED Voltage (VDC) Diagnostic Bit
Without Activation OFF 9-12 1
Activated ON 2-3 0
N.C. 2 Wire 12V Proximity Sensor: (Black lead to ground and red lead to the brown wire)
Proximity Sensor State LED Voltage (VDC) Diagnostic Bit
Without Activation ON 2-3 0
Activated OFF 9-12 1
N.O. 3 Wire 12V Proximity Sensor: (Black lead to ground and red lead to the black wire)
Proximity Sensor State LED Voltage (VDC) Diagnostic Bit
Without Activation OFF 9-12 1
Activated ON 0-2 0
For 12 VDC proximity sensors, test the voltage atthe proximity sensor. The 3-wire 5 VDC sensorreceives voltage from the processor PCB. It is thesame voltage that is sent to the axis encoder. Ifthe axis encoder works correctly, and there areno encoder alarms, the sensor receives thecorrect voltage.
Always check for voltage from the back of theconnector with needle-tip probes. If there isvoltage present at the proximity sensor, but it willnot change status, the sensor is at fault.
Proximity Sensor - Troubleshooting Guide
Page 4 of 5 pages
N.C. 3 Wire 5V Proximity Sensor - Home Switches: (Black lead to ground and red lead to the blackwire)
Proximity Sensor State LED Voltage (VDC) Diagnostic Bit
Without Activation OFF 0-2 0
Activated ON 3-5 1
Proximity Sensor - Troubleshooting Guide
Page 5 of 5 pages
