The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 16, 1998
Filed:
Jan. 30, 1997
Otis Elevator Company, Farmington, CT (US);
Abstract
An elevator drive fault detector for detecting operational faults in an elevator drive having an inverter and only one circuit breaker includes a current sensor, a monitoring device, a control device and an operational control system. The current sensor provides a current sensor signal. The monitoring device determines if an operational fault exists in response to the current sensor signal and provides an operational signal. The monitoring device disables the operational signal if the monitoring device determines that an operational fault exists or if the elevator drive fault detector performs a system check operation. The operational control system provides both the run command and an operational check signal and is responsive to the operational signal such that if the operational signal is disabled then the operational control system opens the one circuit breaker and disables the run command such that the control device disables a PWM signal. If the operational signal was disabled during a system check operation then the operational control provides the operational check signal to the monitoring device such that if the monitoring device does not receive the operational check signal within a predetermined time then the monitoring device continues to disable the operational signal and the drive is elevator shutdown.