EE needs NOISE test help
I am looking for a low cost off the shelf equipment to do production NOISE testing of small motors and gearmotors as part of an EOL functional one output shaft revolution test. The output would feed a GO-NO GO result to PLC input(s) or via PLC serial port. After 2.5 to 3 second test, the response time then needs to be less than 2 seconds, prefer 1 second or less. There are two independant test stations, using one mid-hi range PLC (GE 90/30 w/ 364 CPU).
SPL / dB testing does not work well as the good and bad units overlap wrt level, by about 50% and ambient noise levels effects noise level readings. Also effecting NOISE test is that the output gear is contacted by a cone-encoder to get direction of rotation and degrees of travel during test, which is more important than the noise test.
Right now I assume I need a microphone input to SIMPLE FFT equipment that the PLC downloads freq band hi-lo limits to. A model is selected and ran for hours at a time, a batch model operation. Direct contact ( accelerometer ) is not practical.
Any equipment recommendations, < $ 2,500 per channel.
Dennis McHenney
mchenney@mindspring.com
I am looking for a low cost off the shelf equipment to do production NOISE testing of small motors and gearmotors as part of an EOL functional one output shaft revolution test. The output would feed a GO-NO GO result to PLC input(s) or via PLC serial port. After 2.5 to 3 second test, the response time then needs to be less than 2 seconds, prefer 1 second or less. There are two independant test stations, using one mid-hi range PLC (GE 90/30 w/ 364 CPU).
SPL / dB testing does not work well as the good and bad units overlap wrt level, by about 50% and ambient noise levels effects noise level readings. Also effecting NOISE test is that the output gear is contacted by a cone-encoder to get direction of rotation and degrees of travel during test, which is more important than the noise test.
Right now I assume I need a microphone input to SIMPLE FFT equipment that the PLC downloads freq band hi-lo limits to. A model is selected and ran for hours at a time, a batch model operation. Direct contact ( accelerometer ) is not practical.
Any equipment recommendations, < $ 2,500 per channel.
Dennis McHenney
mchenney@mindspring.com
