Test method and system for uninterruptible power supply

• US 6,236,226 B1
• Filed: 11/04/1998
• Issued: 05/22/2001
• Est. Priority Date: 11/05/1997
• Status: Expired due to Fees

• Current Assignee: HTC Corporation
• Original Assignee: NEC Corporation
• Inventors: Hagiwara, Yoshihiro
• Primary Examiner(s): Metjahic, Safet
• Assistant Examiner(s): KERVEROS, DEMETRIOS C
• Application Number:
  US09/186,016
• Time in Patent Office: 930 Days
• Field of Search: 324/771, 324/430, 324/429, 324/426, 320/106, 320/107, 320/112, 320/113, 320/131, 320/132, 320/118, 320/128, 320/135, 307/64
• US Class Current: 324/764.01
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10

Abstract

In a system composed of an uninterruptible power supply UPS) and a computer that is supplied with power from the UPS, the UPS includes a test switch that is turned off by the control of the computer until a test time period has elapsed. The computer includes a test flag memory that holds its data when the UPS does not supply power to the computer. The computer uses the test flag memory to determine whether the UPS is under abnormal conditions.

Claims

1. A system for testing an uninterruptible power supply that inputs external power from an external power source and supplies power to equipment that is electrically connected to the uninterruptible power supply, wherein the uninterruptible power supply comprises:

a backup power supply for supplying continuous power to the equipment when the external power is interrupted;

a test switch connected between the backup power supply and the external power source; and

a switch controller for, during a test of the uninterruptible power supply, opening the test switch in response to a test start signal and closing the test switch after a lapse of a first predetermined time period of the switch controller, and wherein the equipment comprises;

a memory for storing a test flag that is maintained in memory when the uninterruptible power supply does not supply power to the equipment during the test; and

a test controller for performing test control such that the test start signal is output to the switch controller when the test flag is set to a first state and , if power is normally supplied from the uninterruptible power supply during a second predetermined time period of the test controller shorter than the first predetermined time period of the switch controller, then the test flag is reset to a second state, and further, the test controller determining that the backup power supply is in an abnormal condition when the test flag is in the first state with power supplied from the uninterruptible power supply after a lapse of the first predetermined time period of the switch controller and determining that the backup power supply is in a normal condition when the test flag is reset to the second state after a lapse of the second predetermined time period of the test controller.

2. The system according to claim 1, wherein the equipment further comprises a monitor, wherein the test controller displays information on the monitor indicating a failure occurring in the uninterruptible power supply when the test controller determines that the backup power supply is in an abnormal condition.

3. The system according to claim 2, wherein the test controller controls the monitor to display information indicating a normal condition of the uninterruptible power supply when the test flag is reset to the second state after a lapse of the second predetermined time period.

4. The system according to claim 1, wherein the test flag memory is a nonvolatile memory.

5. The system according to claim 1, wherein the memory is backed up by a battery incorporated in the equipment.

6. The system according to claim 1, wherein the equipment further comprises:

a power supply circuit for inputting power from the uninterruptible power supply and supplying power to necessary devices of the equipment.

7. The system according to claim 6, wherein the equipment is a computer having a program-controlled processor therein, and wherein the test controller is implemented with a test control program running on the program-controlled processor.

8. An apparatus which is electronically connected to an uninterruptible power supply that inputs external power from an external power source and supplies power to the apparatus, the uninterruptible power supply including:

a backup power supply for supplying continuous power to the apparatus when the external power is interrupted;

a test switch connected between the backup power supply and the external power source; and

a switch controller for, during a test of the uninterruptible power supply, opening the test switch in response to a test start signal and closing the test switch after a lapse of a first predetermined time period of the switch controller, the apparatus comprising;

a display for displaying necessary information;

a memory for storing a test flag that is maintained in memory when the uninterruptible power supply does not supply power to the equipment during the test;

a timer for measuring a second predetermined time period shorter than the first predetermined time period; and

a test controller for performing test control such that the test start signal is output to the switch controller and the timer is started when the test flag is set to a first state and, if power is supplied normally from the uninterruptible power supply until a timeout occurs at the timer, then the test flag is rest to a second state, and further, the test controller determining that the backup power supply is in an abnormal condition when the test flag is in the first state with power supplied from the uninterruptible power supply after a lapse of the first predetermined time period of the switch controller and determining that the backup power supply is in a normal condition when the test flag is reset to the second state after a lapse of the second predetermined time period of the test controller.

9. The apparatus according to claim 8, wherein the test controller displays information on the display indicating a failure occurring in the uninterruptible power supply when the test controller determines that the backup power supply is in an abnormal condition.

10. The apparatus according to claim 9, wherein the test controller controls the monitor to display information indicating a normal condition of the uninterruptible power supply when the test flag is reset to the second state after a lapse of the second predetermined time period.

11. The apparatus according to claim 8, further comprising a power supply circuit for inputting power from the uninterruptible power supply and supplying power to necessary devices thereof.

12. The apparatus according to claim 11, wherein the test controller is implemented with a test control program running on a program-controlled processor.

13. A method for testing an uninterruptible power supply that inputs external power from an external power source and supplies power to equipment that is electrically connected to the uninterruptible power supply, the uninterruptible power supply having a backup power supply for supplying continuous power to the equipment when the external power is interrupted, a test switch connected between the backup power supply and the external power source, the method comprising the steps of:

at the uninterruptible power supply,

a) during a test of the uninterruptible power supply, opening the test switch in response to a test start signal and closing the test switch after a lapse of a first predetermined time period of a switch controller;

at the equipment,

b) storing a test flag that is maintained in memory when the uninterruptible power supply does not supply power to the equipment during the test;

c) setting the test flag to a first state when outputting the test start signal to the switch controller;

d) resetting the test flag to a second state when power is supplied normally from the uninterruptible power supply during a second predetermined time period of a test controller which is shorter than the first predetermined time period of the switch controller; and

e) determining that the backup power supply is in an abnormal condition when the test flag is in the first state with power supplied from the uninterruptible power supply during the test after a lapse of the first predetermined time period of the switch controller and determining that the backup power supply is in a normal condition when the test flag is reset to the second state after a lapse of the second predetermined time period of the test controller.

14. The method according to claim 13, further comprising a step of displaying information on a screen indicating a failure occurring in the uninterruptible power supply when the test controller determines that the backup power supply is in an abnormal condition.

15. The method according to claim 13, further comprising a step of displaying information on a monitor indicating a normal condition of the uninterruptible power supply when the test flag is reset to the second state after a lapse of the second predetermined time period.

16. A storage medium for storing a test control program that is executed by a computer which is supplied with power by an uninterruptible power supply comprising:

a backup power supply for supplying continuous power to equipment when the external power is interrupted;

a test switch connected between the backup power supply and the external power source; and

a switch controller for, during a test of the uninterruptible power supply, opening the test switch in response to a test start signal and closing the test switch after a lapse of a first predetermined time period of the switch controller, the test control program comprising the steps of;

a) storing a test flag that is maintained in memory when the uninterruptible power supply does not supply power to the equipment during the test;

b) setting the test flag to a first state when outputting the test start signal to the switch controller;

c) resetting the test flag to a second state when power is supplied normally from the uninterruptible power supply during a second predetermined time period of a test controller which is shorter than the first predetermined time period of the switch controller; and

d) determining that the backup power supply is in an abnormal condition when the test flag is in the first state with power supplied from the uninterruptible power supply during the test after a lapse of the first predetermined time period of the switch controller and determining that the backup power supply is in a normal condition when the test flag is reset to the second state after a lapse of the second predetermined time period of the test controller.