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Hi JRoss, Okay, thank you for your insight. Cheers,

Hi Carples, Thank you for your email. I don't know how to reset the counter (present and previous value), by using a software command. Or should I use external reset request? Then again the timing for reset request is very critical. The inverter that my customer using is Yaskawa Inverter G7A Series. I can't use the pulse train input, as I need to do some calculation inside the PLC which depends on the setting on the HMI and production request. And send the calculated number, which represent the speed as Analog Signal to the Inverter.

Hi Jross, Thanks again for your email. Yes, that's what I'm worried if using Sampling Counter, because to keep, as if it continues reading the pulse, there will be conflict at the end of T periodic with the rising edge. I was looking into the periodic pulse counter too, but I have another question. To get a real time value at T periodic, I must have it by subtracting the present value with previous value buffer. But if the machine continues in operation, say for an extreme example, it is running continuously and at a certain time, the value of the pulse is incrementing (never decrementing), it may have reached its maximum value (32 signed bit), that it must go back to zero. I found it difficult when I must do subtraction. That's what my concern is. Any idea? Yes, I have the Manual Book of QD62. Thanks a lot!

Hi JRoss, Thanks for your reply. By using this Sampling Counter to read the RPM, is it okay that I create a periodic PULS timing that will enable counter (at Y06) without any "empty time space" (I don't know if this is the correct word). As this is meant for Sampling not periodic? Is the buffer can be refreshed and read immediately as T time is reached but at the same time the periodic PULS is also generated? Please advise. Thank you.

Hi JRoss, Thanks for your reply. By using this Sampling Counter to read the RPM, is it okay that I create a periodic PULS timing that will enable counter (at Y06) without any "empty time space" (I don't know if this is the correct word). As this is meant for Sampling not periodic? Is the buffer can be refreshed and read immediately as T time is reached but at the same time the periodic PULS is also generated? Please advise. Thank you.

Hi Guys, I have a project of modifying an existing system that will have to put a new inverter and synchronize it with the existing Main Line Rotating Shaft. The existing system is using Q01CPU and it has 3 spare slot that I can use to put a new module and modify the program. What I need is to install an incremental rotary encoder and read the rotation speed (in rpm) and then send an analog signal as the speed reference to the new inverter. I was thinking of putting QD62. However after reading the QD62 Manual I don't see any particular function that referring to reading the rotation speed. I have done programming using FX2N and FX3U, and it was very easy to read the rotation speed by using SPD command. So, now I'm wondering whether I can use QD62 or should I use other module? Can someone enlighten me on this one? Thank you very much guys! Cheers, Kaew