Contract hour configuration when CD_FIELD_DEVICE_AGGREGATES = Y

If your system is configured with a configDesc setting of CD_FIELD_DEVICE_AGGREGATES, the aggregation calculations are preformed using the Field device local timezone and the Field device contract hour.

Thus, when you are changing the contract hour in the Properties, you should ensure that the Effective Time is set to the time in the system contract timezone (defined in CD_CONTRACT_TIMEZONE_CODE) that is equivalent to the time of the new contract hour in the Field Device Local Timezone.

Consider the following example, keeping in mind the dates used reflect the DST change in 2018:

• Field device local timezone for the meter is a standard timezone

• System contract timezone is a timezone that switches between standard and daylight saving time

Assume that the timezones are set as follows:

• System contract timezone = Mountain Daylight (UTC-6)

• Field device local timezone = Atlantic Standard (UTC-4)

• Field device contract hour = 2 PM in the summer, 3 PM in the winter

In the winter, to account for the return to Standard Time, the Field device contract hour would be changed to 3 PM on November 4th. The contract hour change to 3pm should be made effective at Nov 4 12pm MST (UTC-7 hours) in the Properties window, which is Nov 4 3pm AST (UTC-4 hours). The changes are captured in the image below:

In the spring, the contract hour is changed from 3 PM to 2 PM on March 11th 12 PM MDT (UTC-6) in the Properties window, which is March 11th 2 PM AST (UTC-4 hours).

This example uses a twice-yearly contract hour change that coincides with the daylight savings adjustments, but the concept applies to changing the Field device contract hour at any time of the year, not just during a daylight savings change.