6.22 Real time clock (RTC)
The real-time clock is the basis for time-dependent process controls, e.g.:
● To reduce the temperature of a heating control during the night
● To increase the pressure of a water supply at certain times during the day
Function and settings
The real-time clock starts as soon as the Control Unit power supply is switched on for the first
time. The real-time clock comprises the time in a 24 hour format and the date in the "day,
month, year" format.
After a Control Unit power supply interruption, the real-time clock continues to run for approx.
five days.
If you wish to use the real-time clock, you must set the time and date once when commissioning.
If you restore the inverter factory setting, the inverter only resets parameters p8402 and p8405
of the real-time clock. P8400 and p8401 are not reset.
Parameter Real-time clock (RTC)
p8400 RTC time (Factory setting: 0)
[0] Hour (0 … 23)
[1] Minute (0 … 59)
[2] Second (0 … 59)
p8401 RTC date (Factory setting: 1.1.1970)
[0] Day: 1 … 31.
[1] Month 1 (January) … 12 (December)
[2] Year: 1970 … 9999
p8402 RTC daylight saving time setting
The factory setting corresponds to the changeover times for Central European Summer
Time (CEST). To activate the CEST, only p8402[0] = 1 needs to be set.
[0] Difference between daylight saving time and standard time (factory setting: 0 h)
[1] Start of month (factory setting: 3), 1 (January) … 12 (December)
[2] Start of week of month (factory setting: 6)
1: Day 1 … 7, 2: Day 8 … 14, 3: Day 15 … 21, 4: Day 22 … 28, 6: Last seven
days of the month
[3] Start weekday (factory setting: 7), 1 (Monday) … 7 (Sunday)
[4] Start hour (factory setting: 2)
[5] End month (factory setting: 10)
[6] End week of month (factory setting: 6)
1: Day 1 … 7, 2: Day 8 … 14, 3: Day 15 … 21, 4: Day 22 … 28, 6: Last seven
days of the month
[7] End weekday (factory setting: 7), 1 (Monday) … 7 (Sunday)
[8] End hour (factory setting: 3)
r8403 RTC daylight saving time difference actual [hours]
Displays the actual difference between standard time and daylight saving time.
r8404 RTC weekday, 1: Monday … 7: Sunday
Advanced commissioning
6.22 Real time clock (RTC)
Converter with the CU230P-2 Control Units
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34257946B AE 293