What could be causing the drive overload error?07/14/2017AC drives are rated according to input voltage and current rating. As long as the motor that is being ran with the drive has a full load amp rating that is below the rated current of the drive, the motor and drive will work and play well together. For example, if you have a motor that has an input voltage rating of 480 volts and a full load amp rating of 45 amps, in terms of horsepower, this rating is approximately 30 horsepower, you would want to have a drive that is sized accordingly. That is to say the drive should be rated at an input voltage of 480 volts with an output voltage of 480 volts and rated for approximately 45 to 60 amps.Let’s say you have a Baldor AC drive that is a model ZD18H430L. This is a drive that is rated at 30 horsepower at 480 volts. This is an older drive as of this writing and we will assume that it has been in your system for years, programmed correctly and running smoothly. Now you’re getting an overload fault. This particular Baldor drive has two different overload fault indications. The first is Overload – 3 Sec FLT, which means that the peak output current exceeded the three second rating. The other Overload fault is Overload – 1 Min FLT, which means that the peak output current exceeded the one minute rating. *For constant torque, the 3 Sec FLT rating is 170 – 200% and the 1 Min FLT rating is 150%. The first step in troubleshooting is to verify that the PK Current Limit parameter in the Level 2 Output Limits block is what you expect it to be and has not been changed since your application has been running correctly previously. You can also change the parameter setting from Trip to Foldback to see if that will solve the issue. Check to see if the overload fault condition may be caused by some external factor such as a change in the load. If this is the case you can try to increase the ACCEL and DECEL time parameters accordingly to allow more time to handle the load. If parameter changes yield no positive results, check to see if the overload may be caused by some sort of external cause such as a problem with the motor. Is the motor bound up causing an excessive current draw or is there a problem with the encoder? If the encoder coupling is broken, loose and slipping, or if it has become mis-aligned, it may cause the fault. A bad bearing in the encoder may also be the reason.If you have tried all of these measures and are still getting either the three second or one minute overload fault conditions, it is most likely an issue internal to the drive. Call 800-732-4695 to contact the Baldor specialists here at PES and we will be glad to help get you going again. Back To Blog
What could be causing the drive overload error?07/14/2017AC drives are rated according to input voltage and current rating. As long as the motor that is being ran with the drive has a full load amp rating that is below the rated current of the drive, the motor and drive will work and play well together. For example, if you have a motor that has an input voltage rating of 480 volts and a full load amp rating of 45 amps, in terms of horsepower, this rating is approximately 30 horsepower, you would want to have a drive that is sized accordingly. That is to say the drive should be rated at an input voltage of 480 volts with an output voltage of 480 volts and rated for approximately 45 to 60 amps.Let’s say you have a Baldor AC drive that is a model ZD18H430L. This is a drive that is rated at 30 horsepower at 480 volts. This is an older drive as of this writing and we will assume that it has been in your system for years, programmed correctly and running smoothly. Now you’re getting an overload fault. This particular Baldor drive has two different overload fault indications. The first is Overload – 3 Sec FLT, which means that the peak output current exceeded the three second rating. The other Overload fault is Overload – 1 Min FLT, which means that the peak output current exceeded the one minute rating. *For constant torque, the 3 Sec FLT rating is 170 – 200% and the 1 Min FLT rating is 150%. The first step in troubleshooting is to verify that the PK Current Limit parameter in the Level 2 Output Limits block is what you expect it to be and has not been changed since your application has been running correctly previously. You can also change the parameter setting from Trip to Foldback to see if that will solve the issue. Check to see if the overload fault condition may be caused by some external factor such as a change in the load. If this is the case you can try to increase the ACCEL and DECEL time parameters accordingly to allow more time to handle the load. If parameter changes yield no positive results, check to see if the overload may be caused by some sort of external cause such as a problem with the motor. Is the motor bound up causing an excessive current draw or is there a problem with the encoder? If the encoder coupling is broken, loose and slipping, or if it has become mis-aligned, it may cause the fault. A bad bearing in the encoder may also be the reason.If you have tried all of these measures and are still getting either the three second or one minute overload fault conditions, it is most likely an issue internal to the drive. Call 800-732-4695 to contact the Baldor specialists here at PES and we will be glad to help get you going again.