Hi all,
I have a machine that is > 10 years old. It's running with a DC motor and a Siemens DC drive. It's been running ok for years so should be no problem with sizing of the drive or anything like that.
When the machine is under no load, it can run at 100% speed with no issues. The tacho is wired to the drive, and this is normalised by the drive to give a 0-10V speed output which goes to a meter indicating speed. This all works fine.
However, when the machine is under load, and the setpoint is 100%, checking with a hand tacho reveals that it's only about 86% speed. However, what I find most odd is that the speed meter still indicates 100%.
The drive is a Simoreg 6RA24, and according to parameter P740, the analog output the meter is connected to is Actual Speed. So the speed readout might not not be direct from the tacho, but it is derived from it.
We know that the comm of the motor is a bit worn and scored.
Any ideas what the problem might be?
I have a machine that is > 10 years old. It's running with a DC motor and a Siemens DC drive. It's been running ok for years so should be no problem with sizing of the drive or anything like that.
When the machine is under no load, it can run at 100% speed with no issues. The tacho is wired to the drive, and this is normalised by the drive to give a 0-10V speed output which goes to a meter indicating speed. This all works fine.
However, when the machine is under load, and the setpoint is 100%, checking with a hand tacho reveals that it's only about 86% speed. However, what I find most odd is that the speed meter still indicates 100%.
The drive is a Simoreg 6RA24, and according to parameter P740, the analog output the meter is connected to is Actual Speed. So the speed readout might not not be direct from the tacho, but it is derived from it.
We know that the comm of the motor is a bit worn and scored.
Any ideas what the problem might be?