Synchronization Of The Load Profile - Siemens SENTRON PAC4200 Manual

2.4.3

Synchronization of the load profile

The device expects the synchronization pulse at the start of the period.
The synchronization can be initiated by several means:
● By a synchronization pulse at the digital input
● By a synchronization command via the communication interface
● By the internal clock of the device
Handling of irregular, external synchronization pulses
SENTRON PAC4200 checks whether the external synchronization pulse is received at the
set time, too soon, too late, or not at all. If the deviation from the set time exceeds a defined
tolerance, this results in a shorter period.
If the complete time frame for received pulses is offset, SENTRON PAC4200 automatically
adapts to the new time frame.
Synchronization via the communication interface
The synchronization frame contains the length of the subperiod in minutes. The
synchronization command is ignored if the period length sent to the device with the
synchronization frame is different to the length parameterized in the device.
Synchronization via the internal clock
The length of the subperiod, and thus also the demand period, is determined solely by the
internal clock.
A subperiod starts on the full hour plus a multiple of the configured subperiod length.
Correction of the time during the current demand period or beyond the end of the demand
period results in shorter demand periods. SENTRON PAC4200 marks these periods with the
valuation indicator "resynchronized".
It does not record any substitute values for the gaps that are created in the time history.
Response to powering up
All load profiles that have already been recorded remain unchanged.
SENTRON PAC4200 resets the internal clock if it detects load profiles with a date in the
future or a time in the past on powering up.
Impact of a tariff change on the load profile
Tariff changes between off-peak and on-peak have an impact on the load profile because all
values stored in the profile are uniquely assigned to the applicable tariff.
The last tariff remains valid until the end of the instantaneous period. The new tariff takes
effect at the start of the next period. The energy counters of SENTRON PAC4200 are
switched to the other tariff at the end of the instantaneous demand period.
PAC4200
System Manual, 05/2019, A5E02316180B-05
Description
2.4 Load profile
29