Proface APL3000B - Node Box PC - Manual (Page 27)

PS-3650A/PS-3651A Series Hardware Manual
2-6
*3 The RTC clock built in the PS-A unit has a timing error. The range of the error will be between +300
to -300 sec. / month, depending on the PS-A unit’s conditions such as lifetime usage or temperature
difference. If you use the PS-A unit in a system that is very dependent on timing, adjust the clock at
regular intervals.