SYSTEM AND METHOD FOR MANAGING TIME IN AUTOMATIC CONTROL EQUIPMENT

• US 20080267328A1
• Filed: 04/14/2008
• Published: 10/30/2008
• Est. Priority Date: 04/24/2007
• Status: Active Grant

• Current Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Original Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Inventors: IANNI, Giovanni, PIACIBELLO, Jacques
• Granted Patent: US 7,983,115 B2
• Time in Patent Office: Days
• US Class Current: 375/354
• CPC Class Codes: G06F 1/14 Time supervision arrangements, e.g. real time clock

Abstract

The present invention relates to a time management method implemented in automatic control equipment, based on a system which comprises:

• • a first clock (H1) having a first counter (C1) operating on a first timebase,
  • a second clock (H2) having a second counter (C2) operating on a second timebase identical to the first timebase and a third counter (C3) operating on a third timebase less than the second timebase,
    said time management method being characterized in that it consists notably in:
  • performing a resynchronization of the second clock (H2) after the main electrical power supply (G1) has been restored, this resynchronization consisting, on a modification of the first counter (C1), in loading the first counter (C1) into the second counter (C2) and in zeroing the third counter (C3).

Claims

1. Time management method implemented in automatic control equipment, based on a system which comprises:

a first clock (H1) having a first counter (C1) operating on a first timebase,

a second clock (H2) having a second counter (C2) operating on a second timebase identical to the first timebase, and a third counter (C3) operating on a third timebase less than the second timebase,

a main electrical power supply (G1) for powering the first and second clocks,

an auxiliary electrical power supply (G2) for powering the first clock (H1) in the event of a main electrical power supply outage,

said time management method being characterized in that it consists in;

performing a periodic synchronization between the first counter (C1) and the second counter (C2), and

performing a resynchronization of the second clock (H2) when the main electrical power supply (G1) is restored, this resynchronization consisting, on a modification of the first counter (C1), in loading the first counter (C1) into the second counter (C2) and in zeroing the third counter (C3).

2. Method according to claim 1, characterized in that the first clock (H1) is a hardware component of RTC type.

3. Method according to claim 1 or 2, characterized in that the first timebase is the second.

4. Method according to one of claims 1 to 3, characterized in that the second clock (H2) is incremented by software.

5. Method according to one of claims 1 to 4, characterized in that the third timebase is the millisecond.

6. Method according to one of claims 1 to 5, characterized in that the auxiliary electrical power supply (G2) is a capacitor.

7. Method according to one of claims 1 to 6, characterized in that the periodic synchronization is performed on the basis of the second counter (C2) of the second clock (H2).

8. Time management system in automatic control equipment, characterized in that it comprises:

a first clock (H1) having a first counter (C1) operating on a first timebase,

a second clock (H2) having a second counter (C2) operating on a second timebase identical to the first timebase and a third counter (C3) operating on a third timebase less than the second timebase,

means for periodically synchronizing the second counter (C2) and the first counter (C1),

a main electrical power supply (G1) for powering the first and second clocks (H1, H2),

an auxiliary electrical power supply (G2) for powering the first clock (H1) in the event of an outage of the main electrical power supply (G1),

means for performing a resynchronization of the second clock (H2) after the end of a main electrical power supply outage,

said resynchronization consisting, on a modification of first counter (C1), in loading the first counter (C1) into the second counter (C2) and in zeroing the third counter (C3).

9. System according to claim 8, characterized in that the first clock (H1) is a hardware component of RTC type.

10. System according to claim 8 or 9, characterized in that the first timebase is the second.

11. System according to one of claims 8 to 10, characterized in that the second clock (H2) is controlled by software.

12. System according to one of claims 8 to 11, characterized in that the third timebase is the millisecond.

13. System according to one of claims 8 to 12, characterized in that the auxiliary electrical power supply (G2) is a capacitor.