System and method for automatically securing a motor control center

• US 7,561,412 B2
• Filed: 09/29/2006
• Issued: 07/14/2009
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Brandt, David D., Jensen, David L.
• Primary Examiner(s): Abrams; Neil
• Application Number:
  US11/541,294
• Publication Number:
  US 20080081516A1
• Time in Patent Office: 1,019 Days
• Field of Search: 439/142, 439/911, 361/1, 361/212, 361/115, 361/609, 361/616, 307/328, 200/50.02, 200/50.12, 200/50.17, 340/506, 340/521
• US Class Current: 361/616
• CPC Class Codes: H02B 1/36 with withdrawable units
• CPC Class Codes: H02B 13/025 Safety arrangements, e.g. in case of excessive pressure or fire due to electrical defect
• CPC Class Codes: H02B 13/065 Means for detecting or reacting to mechanical or electrical defects

Abstract

A system, in one embodiment, includes a power distribution center having an enclosure with an access door configured to move between a closed position and an open position. The system also includes a monitoring system configured to monitor operational parameters inside the enclosure. Also, the system includes an entry control system coupled to the monitoring system, wherein the entry control system is configured to lock the access door if the operation parameters are indicative of a potentially hazardous condition inside the enclosure.

Claims

1. A system, comprising:

a power distribution center, comprising;

an enclosure comprising an access door configured to move between a closed position and an open position;

a monitoring system comprising one or more sensors configured to monitor operational parameters inside the enclosure without user access into the enclosure;

an indicator coupled to the monitoring system, wherein the indicator is configured to provide an indication of the operational parameters inside the enclosure without user access into the enclosure; and

an entry control system coupled to the monitoring system and the indicator, wherein the entry control system is responsive to the operational parameters monitored by the monitoring system, the entry control system is configured to lock the access door if the operation parameters are indicative of a potentially hazardous condition inside the enclosure, and the entry control system comprises a lock override configured to unlock the access door to enable user access into the enclosure during the potentially hazardous condition only after user acknowledgment of the potentially hazardous condition as indicated by the indicator.

2. The system of claim 1, wherein the entry control system comprises an auto lock/unlock mechanism coupled to the access door and controlled by the entry control system, and the entry control system is configured to automatically move a lock or latch between a locked position and an unlocked position in response to the operational parameters monitored by the monitoring system and a user access request for entry into the enclosure.

3. The system of claim 1, wherein the indicator comprises an audio alarm, a video alarm, or a combination thereof, and the entry control system is configured to control the indicator to alarm a user of the potentially hazardous condition at least when a user requests access for entry into the enclosure.

4. The system of claim 1, wherein the one or more sensors comprise a touchless voltage sensor coupled to the monitoring system.

5. The system of claim 4, wherein the touchless voltage sensor comprises a plurality of electric-field sensors electrically isolated from monitored components in the enclosure, and the electric-field sensors are electrically isolated from the monitoring system via opto-isolators, wireless tranceivers, optical cables, or a combination thereof.

6. The system of claim 1, comprising a thermal radiation sensor coupled to the monitoring system.

7. The system of claim 1, wherein the indicator comprises an external display coupled to the monitoring system and the entry control system.

8. The system of claim 1, comprising a wireless communication link coupled to the monitoring system and a plurality of the sensors distributed throughout the enclosure, and the wireless communication link is configured to electrically isolate the plurality of sensors from the monitoring system.

9. The system of claim 1, wherein the one or more sensors comprise a plurality of non-contact sensors electrically isolated from the monitoring system via respective optical cables.

10. The system of claim 1, wherein the one or more sensors comprise a plurality of touchless voltage sensors each configured to measure different levels of electrical fields emanating from components within a group to determine if certain components in the group are energized or de-energized.

11. The system of claim 10, wherein the monitoring system comprises a sensor baseline setup having a plurality of voltage measurements for each touchless voltage sensor, the plurality of voltage measurements correspond to different permutations of components being turned on and off, and the monitoring system is configured to compare the sensor baseline setup against actual voltage measurements during operation of the power distribution center.

12. The system of claim 1, wherein the entry control system comprises a solenoid-actuated latch responsive to the entry control system to automatically lock and unlock the access door based on the operational parameters monitored by the monitoring system.

13. The system of claim 1, wherein the one or more sensors comprise a plurality of non-contact temperature sensors and a plurality of non-contact voltage sensors distributed throughout the enclosure, each sensor is configured to monitor a group of components, each sensor is electrically isolated from the components, each sensor is electrically isolated from the monitoring system via a wireless or optical communication link, and each sensor communicates data for use with the monitoring system and the entry control system.

14. The system of claim 1, wherein the monitoring system comprises a data logging system configured to continuously monitor and log temperature and voltage data from the one or more sensors, generate historical/trend graphs or profiles, load or modify control schemes based on the data, and enable dynamic sensor control based on the data.

15. A system, comprising:

a monitoring system configured to mount to a power distribution center, wherein the monitoring system comprises a thermal radiation sensor and an electric field sensor disposed inside the power distribution center and configured to measure operational conditions inside the power distribution center, and the operational conditions comprise a potentially hazardous condition inside the power distribution center;

an auto lock mechanism configured to move between a locked position and an unlocked position of a door of the power distribution center in response to a control signal; and

an entry control system coupled to the monitoring system and the auto lock mechanism, wherein the entry control system is configured to transmit the control signal to the auto lock mechanism in response to the operational conditions measured inside the power distribution center, and the entry control system is configured to control the auto lock mechanism to move from the unlocked position to the locked position or maintain the locked position if the measured operational conditions indicate the potentially hazardous condition within the power distribution center;

wherein the entry control system comprises a lock override configured to override the auto lock mechanism from the locked position to the unlocked position during operation of the power distribution center while the measured operational conditions indicate the potentially hazardous condition, after user acknowledgement of the potentially hazardous condition indicated by an indicator, to enable user entry into the power distribution center during the potentially hazardous condition.

16. The system of claim 15, wherein the auto lock mechanism comprises a solenoid operated door latch, or a motor driven lock, or a combination thereof, responsive to the control signal from the entry control system.

17. The system of claim 15, wherein the indicator comprises an audio alarm, a visual alarm, or a combination thereof, controlled by the entry control system and indicative of the potentially hazardous condition.

19. The system of claim 15, wherein the thermal radiation sensor comprises a thermopile, a radiation pyrometer, an infrared detector, or a combination thereof.

20. The system of claim 15, wherein the thermal radiation sensor and the electric field sensor are both electrically isolated from the monitoring system via respective optical cables.

21. The system of claim 15, wherein the electric field sensor is configured to measure different levels of electrical fields emanating from components within a group to determine if certain components in group are energized or de-energized.

22. The system of claim 21, wherein the monitoring system comprises a sensor baseline setup having a plurality of voltage measurements for the electric field sensor, the plurality of voltage measurements correspond to different permutations of components being turned on and off, and the monitoring system is configured to compare the sensor baseline setup against actual voltage measurements during operation of the power distribution center.

23. The system of claim 15, wherein the monitoring system comprises a data logging system configured to continuously monitor and log temperature and voltage data from the thermal radiation sensor and the electric field sensor, generate historical/trend graphs or profiles, load or modify control schemes based on the data, and enable dynamic sensor control based on the data.

18. The system of clam 15, comprising a wireless communication link configured to facilitate wireless communications of sensed data and electrically isolate the thermal radiation sensor and electric field sensor from the monitoring system and the entry control system.

24. A method, comprising:

sensing voltage of one or more components within a power distribution center via one or more sensors inside the power distribution center without user access into the power distribution center;

identifying a power state of the one or more components based on the voltage sensed by the one or more sensors within the power distribution center via an indicator disposed outside of the power distribution center, wherein identifying the power state comprises indicating a potentially hazardous condition within the power distribution center during operation of the power distribution center;

controlling an auto lock mechanism of an access door between a secured position and an unsecured position relative to the power distribution center based on the sensed voltage and identified power state, wherein controlling comprises automatically moving the auto lock mechanism to the secured position and maintaining the secured position if the power state is energized to the potentially hazardous condition within the power distribution center; and

overriding the auto lock mechanism of the access door from the secured position to the unsecured position during operation of the power distribution center while the power state is energized to the potentially hazardous condition, after user acknowledgement of the potentially hazardous condition indicated by the indicator, to enable user entry into the power distribution center during the potentially hazardous condition.

25. The method of claim 24, wherein sensing voltage comprises detecting an electric field from the one or more components.

26. The method of claim 24, wherein identifying the power state comprises displaying the power state via a display screen at a destination external to the power distribution center.

27. The method of claim 24, wherein overriding comprises automatically moving the auto lock mechanism from the secured position to the unsecured position in response to user input via a keyboard or touch screen.