Methods of Fitting and Retrofitting Transformers with Fault Indicators, and Fault Indicators Therefor

Abstract

Fault-indicator assemblies that can each be mounted externally to a corresponding electronic device to provide a visual indication that an internal fault has occurred within the electronic device. A fault-indicator assembly of the present disclosure can be configured for electrical devices such as electrical power transformers, capacitors, and reactors, among others. Some embodiments can be configured to connect to existing orifices of a conventionally manufactured electronic device, such as an orifice for a conventional pressure-relief valve. Such embodiments can be deployed without any modifications to the electrical devices and can be readily retrofitted to existing electrical devices. In some embodiments, a pressure-relief valve can be integrated with the fault-indicator assembly to provide both fault-indication functionality and pressure-relief functionality in the same assembly.

What is claimed is: 
     
         1 . A method of fitting an electrical transformer with a fault indicator that indicates when the electrical transformer has experienced a fault that causes an internal pressure increase within an interior space of the electrical transformer, wherein the electrical transformer has a preexisting pressure-relief-valve port designed and configured to receive a conventional pressure-relief valve, the method comprising:
 providing a fault-indicator assembly comprising:
 a pressure-relieve valve; 
 a pressure-activated actuator operatively coupled to an onboard visual indicator or a communication trigger, or both an onboard visual indicator and a communication trigger, wherein the fault-indicator assembly is provided to sense when the internal pressure has increased in a manner characteristic of a fault occurring with the electrical transformer; and 
 a fitting designed and configured to engage the preexisting pressure-relief-valve port; and 
   securing the fault-indicator assembly to the electrical transformer, wherein the securing includes engaging the fitting of the fault-indicator assembly with the preexisting pressure-relief-valve port.   
     
     
         2 . The method of  claim 1 , wherein the conventional pressure-relief valve is initially engaged with the preexisting pressure-relief-valve port, and the method further comprises, prior to engaging the fitting of the fault-indicator assembly with the preexisting pressure-relief-valve port, disengaging the conventional pressure-relief valve from the preexisting pressure-relief-valve port. 
     
     
         3 . The method of  claim 2 , wherein the electrical transformer is a transformer already deployed for use, and the method is a method of retrofitting the electrical transformer with the fault-indicator assembly. 
     
     
         4 . The method of  claim 1 , wherein the preexisting pressure-relief-valve port is a threaded port, and the fitting is threaded to threadingly engage the threaded port. 
     
     
         5 . The method of  claim 1 , wherein the electrical transformer has an exterior sidewall, and the preexisting pressure-relief-valve port is in the exterior sidewall. 
     
     
         6 . The method of  claim 1 , wherein the preexisting pressure-relief-valve port defines an opening having a central axis, and the pressure-relief valve and the fitting lie along the central axis. 
     
     
         7 . The method of  claim 6 , wherein the onboard visual indicator extends away from the central axis. 
     
     
         8 . The method of  claim 7 , wherein the onboard visual indicator extends radially away from the central axis. 
     
     
         9 . The method of  claim 1 , wherein the pressure-activated actuator is fluidly connected to the fitting fluidly upstream of the pressure-relief valve. 
     
     
         10 . The method of  claim 1 , wherein the onboard visual indicator is present and the communication trigger is not present. 
     
     
         11 . The method of  claim 1 , wherein the communication trigger is present and the fault-indicator assembly further includes a communication module designed and configured to communicate a fault-notification signal over one or more networks. 
     
     
         12 . The method of  claim 11 , wherein the pressure-activated actuator comprises an electronic pressure sensor, and the communication trigger comprises circuitry that generates and sends a signal to the communications module when the pressure equals the preset pressure. 
     
     
         13 . The method of  claim 1 , wherein:
 the onboard visual indicator is present; and   the communication trigger is present and the fault-indicator assembly further includes a communication module designed and configured to communicate a fault-notification signal over one or more networks.   
     
     
         14 . The method of  claim 1 , wherein the pressure-activated actuator comprises a deformable component that deforms with changing pressure within the interior space of the electronic device. 
     
     
         15 . The method of  claim 14 , wherein the deformable component comprises a bellows. 
     
     
         16 . The method of  claim 1 , wherein the electrical transformer has a sidewall and, when the fault-indicator assembly is secured to the electrical transformer, longitudinal axes of the fitting and the pressure-relieve valve are colinear and perpendicular to the sidewall, and the pressure-activated actuator extends away from the longitudinal axes of the fitting and the pressure-relief valve. 
     
     
         17 . The method  claim 1 , wherein the onboard visual indicator is present and is movable between a non-fault-indicating position and a fault-indicating position and the fault-indicator assembly further comprises:
 a catch operatively engaged with the onboard visual indicator, the catch maintaining the onboard visual indicator in the non-fault-indicating position until triggered to release the onboard visual indicator; and   a trigger responsive to the pressure-activated actuator and operatively engaged with the catch so as to release the catch in response to the trigger being triggered by the pressure-activated actuator.   
     
     
         18 . The method of  claim 17 , wherein the onboard visual indicator comprises an elongate body slidable within a mating receiver along a longitudinal axis between the non-fault-indicating position and the fault-indicating position. 
     
     
         19 . The method of  claim 18 , further comprising a biasing means that biases the elongate body toward the fault-indicating position. 
     
     
         20 . The method of  claim 1 , wherein the pressure-relief valve is configured to release pressure at a first pressure magnitude, the fault-indicator assembly being designed and configured with an adjustable pressure setpoint, wherein, when the adjustable pressure setpoint is set at a magnitude below the first pressure magnitude, the fault-indicator assembly provides a pressure indication that is independent of a rate of increase of the interior space pressure, and, when the adjustable pressure setpoint is set at a magnitude above the first pressure magnitude, the fault indicator assembly provides a pressure indication that is dependent on a rate of increase of the interior space pressure. 
     
     
         21 . The method of  claim 1 , wherein the fault-indicator assembly has an adjustable pressure setpoint that provides a pressure measurement that is selectively configurable as dependent or independent of a rate of increase of the interior space pressure. 
     
     
         22 . The method of  claim 1 , wherein the pressure-activated actuator is configured to detect slow and accumulative pressure increases. 
     
     
         23 . The method of  claim 1 , wherein the onboard visual indicator is present, and the pressure-activated actuator is configured to cause the onboard visual indicator to change to a fault-indicating state in response to a magnitude of pressure within the interior space of the electrical transformer equaling a preset pressure independently of a rate of increase of the pressure within the interior space of the electrical transformer.