Regarding the logging period of the THD of PM8000 or ION9000

[T.Okada]

Hi,

Our customer has asked: “Can you change the THD logging period?”
We believe it may be possible by adjusting the periodic timer settings.
Would changing this setting have any adverse impact on the PQM?
Also, do you know the rationale for the current THD logging period of 60 minutes?
Why wasn’t 15 minutes chosen instead?

Regards,
Okada

[Charles_Murison]

Hello @T.Okada ,

There is more than 1 THD calculation in the ION meter and I may need to know more details. For example, what is the firmware version, what is the template version, which Data recorder you are looking at, what is triggering the record input?

I see 3s logs, 10min logs and 2 hour logs, but not 60 minutes.

Regards,

Charles

[T.Okada]

Hello @Charles_Murison ,

Thank you for your reply.

The firmware version is 4.7.1.

The template version is 4.6.0.

The names of the data record modules are "Harm mean Log" and "Harm high Log"

The trigger of the record input is the "periodic timer module" (default, not changed the settings.).

Regards,

Okada

[Charles_Murison · Accepted solution]

Hello @T.Okada ,

Have you traced back from the data recorders where the information is coming from?
Lets use Harm High as example.

V1 THD high comes from a maximum module linked to V1 THD 3s. The maximum module is reset from Pulse merge module linked to Feedback module linked to Harm High log. Harm High Log record is triggered by periodic timer module Harm Log Trg. Changing the period of the periodic timer module will change the logging interval and reset the maximum module once the recording is complete.

Harm mean Log
V1 THD mean comes from a store module with outputs that are updated by Harm Log Trg. The inputs to the store module come from an Averaging module. The Averaging module is reset with Harm mean reset. Harm Mean reset is from a feedback module linked to the same store module. Store module is linked to the same periodic timer Harm log Trg.

Changing the periodic timer module once applies to both Harm mean and high calculations.

Given the root source of calculations come from modules that update every 3 seconds, you can change the periodic timer module to something like 15 minutes. 

Likely 15 minute values are close in time to the 10 minute values calculated in other modules so likely the 1 hour was used to avoid any confusion.

Regards,

Charles

[T.Okada]

Hi @Charles_Murison,

Thank you for your reply. I understand the reason for the THD recording period. Just to confirm: changing the time period setting from 60 minutes to 15 minutes won’t affect any other functions of the PQM (with the default meter template), is that correct?

Regards,
Okada

[Charles_Murison]

Correct.

[T.Okada]

Hi @Charles_Murison,

Thank you for your reply.

Regards,

Okada