Pulse Coder alarms Troubleshooting APC/SPC (absolute pulse coder or serial pulse coder |
||
What can causes a pulse coder alarm? PLEASE READ THE WARNING TO THE RIGHT BEFORE PROCEEDING |
Warning If an absolute pulse coder is used, you will have to reset home position if the cable is disconnected. Tool change or pallet change position could also be affected if the zero return position is set improperly. Also if not set properly the axis could be moved beyond its allowable stroke causing severe damage to way covers, ballscrew and much more. |
|
Basic encoder troubleshooting:
|
Detailed explanation on encoder problem troubleshooting:Check motor cable connection for coolant contamination. Pull apart the cable end. Many times coolant can get into the cable conduit and run into the plug. Use an airline to blow through the pins. Spray some contact cleaner inside and blow through. Also check to make sure pins are seated properly and wires are all connected in both connectors. Coolant contamination can cause corrosion and cause wires to break off. Pull gently on each wire to make sure the shrink tubing in not the only thing holding the wires on. Sometimes there is an extra circuit board or an extra plug that the encoder may go through before it goes to the drive. Check these connections and board to to see if there is coolant or oil covered. Moving encoder cables could cause damage to the cables, do as last resort. Cables usually take a long time to get if you damage them. Coolant can make them brittle and not flexible. Parameters usually are not the problem unless someone accidentally changed something. |
|
Advanced encoder troubleshooting technics
Note: In some cases it may be much easier and cheaper to order a new drive or encoder and pay the restocking fee instead of swapping components. Depending on the type of machine and axis this may be recommended from a service professional. Remember if a mistake is made you could have two down machines instead on one. You may also take out another drive (though this is usually rare). |
Detailed explanation: Usually swapping sides of a drive is performed if the alarm is constant or will come up just by moving the axis. DO NOT try running program. Warning watch to make sure you are well within the limits of the machine. The machine does not know the axis is swapped. There also may be uncontrolled motion on power up. There may also be parameters stored in drive and not in the control. The drives that hold the parameters themselves are usually the drives for tool magazine, tool changer, turret or pallet changer. |
|
Questions to ask the operator or to observe when the encoder alarm occurs. Which may help locate the problem.
|