Can the combination of HS power meter module's output register and set point module detect disturbance in a half cycle?

[Tomohiro-Okada]

I have a question about detection of disturbance using ION7650's HS power meter module and setpoint module.

I know that HS power meter module can calculate half cycle RMS value of Voltage or Current, Frequency and so on.

I wonder if I connect the HS power meter module's output register to setpoint module's input register,

the combination of the modules  can detect disturbance in a half cycle(8.3ms or 10ms)?

or difference of the update cycles between the modules prevent it from detecting in a half cycle?

Do you have any idea?

Regards,

@Tomohiro-Okada 

[Charles_Murison]

Hello @Tomohiro-Okada 

The direct question is if possible to link the setpoint module to the output of a highspeed module and have the Setpoint module update at high speed. The answer is yes, it is possible to link.

The indirect question would be will this work and that is a larger question that will in part depend on what the desired outcome is.

Regards,

Charles

[Tomohiro-Okada]

Hello @Charles_Murison 

Thank you for your response.

I made example of specific HS power meter modules' connection.

(Please refer to the attached PDF document. I defined some setup registers' values, too.)

In this case, how long does it take to detect disturbance of frequency?

Regards,

Okada

[Charles_Murison]

Hello @Tomohiro-Okada ,

Yes the Setpoint module and digital output modules can be high speed but I do not know what the response time will be between input change (such as frequency) and the state change at the digital output.

Regards,

Charles

[DanL · Accepted solution]

The ION7650 Highspeed Power Meter module measurements are all measured over the previous cycle (1024 samples) and updated every half-cycle (512 samples). 

On the ION7650 the frequency measurement hardware is separate from the digital samples, so alignment of the Frequency output will be +/-0.5 cycles with the operation boundary.

Therefore input signal changes could take up to 1.5 cycles to propagate to the measurement outputs. The ION module processing is designed to complete ALL modules in less than 1 operating period (HighSpeed = 0.5cycles), so the SetPoint and DO modules will complete within another 0.5cycles.

The onboard solid-state digital outputs of the 7650 can have a few milliseconds of hardware response delay depending on the external load characteristics.

I would expect the total latency for this precise scenario to be between 10ms and 50ms.

NOTE: please see safety warnings in the documentation regarding use in control applications

[Tomohiro-Okada]

Hello @DanL,

Thank you for your specific answer!

I interpret your answer as follows

・Setpoint module can detect changes of the HS power meter module's output registers values

    (For examples, HS Vll avg, HS I avg, HS Freq, HS kW tot   *our customer concern about detection of these parameters)

    in a half cycle and if the values are greater than or less than the threshold values, 

    the Setpoint modules can notify it using output resisters without missing.

・Digital output modules can detect above output resisters(connected to force on of the output register )

   of Setpoint modules and output latching alarm.

Are these interpretations correct?

Thanks,

Okada

[DanL]

Yes, I think that sounds correct.

Dan

[Tomohiro-Okada]

Hello @DanL 

Thank you for your reply.

I understand about this.

Regards,

Okada