Abstract: A method that includes obtaining a sensor reading from a sensor installed inside an underground vault and determining whether the sensor reading is indicative of an alarm state. When the sensor reading is indicative of the alarm state, the method obtains at least one new reading and determines whether the sensor reading includes sensor drift based at least in part on the at least one new reading. The alarm state is established when the sensor reading is determined not to include sensor drift. The sensor drift is removed when the sensor reading is determined to include sensor drift.

Abstract: An assembly for harvesting power from one or more power cables. The assembly includes a current transformer operable to harvest power from the one or more power cables and a controller operable to control an amount of power harvested by the current transformer.

Abstract: A tank including a fluid reservoir, a communication module, a controller, and at least one sensor. The fluid reservoir is configured to be in fluid communication with a cable segment. The communication module is configured to communicate with an external device. The sensor is configured to detect an injection parameter value, encode the injection parameter value in a sensor signal, and send the sensor signal to the controller. The controller is configured to automatically instruct the communication module to transmit information to the external device based on the injection parameter value.

Abstract: A tank including a fluid reservoir, a communication module, a controller, and at least one sensor. The fluid reservoir is configured to be in fluid communication with a cable segment. The communication module is configured to communicate with an external device. The sensor is configured to detect an injection parameter value, encode the injection parameter value in a sensor signal, and send the sensor signal to the controller. The controller is configured to automatically instruct the communication module to transmit information to the external device based on the injection parameter value.

Abstract: A method for rejuvenating a strand-blocked cable having a conductor comprised of a plurality of conductor strands with interstitial volume therebetween blocked by a PIB based mastic, the conductor being surrounded by a polymeric cable insulation. The method comprising installing injection adapters that seal the cable ends of the cable and are usable to inject fluid into the interstitial volume between the conductor strands of the cable; elastically expanding the polymeric cable insulation through the application of pressure to the interstitial volume between the conductor strands of the cable; and injecting at least one injection fluid in which the PIB based mastic is mostly insoluble into the interstitial volume between the conductor strands of the cable.

Abstract: A method for rejuvenating a strand-blocked cable having a conductor comprised of a plurality of conductor strands with interstitial volume therebetween blocked by a PIB based strand-block mastic, the conductor being surrounded by a polymeric cable insulation. The method including pre-injection of compressed gas into the conductor strands of the cable at a pressure less than the elastic limit of the cable insulation, and injection of a rejuvenation fluid into the conductor strands of the cable at a pressure less than the elastic limit of the cable insulation.

Abstract: A method that includes obtaining a sensor reading from a sensor installed inside an underground vault and determining whether the sensor reading is indicative of an alarm state. When the sensor reading is indicative of the alarm state, the method obtains at least one new reading and determines whether the sensor reading includes sensor drift based at least in part on the at least one new reading. The alarm state is established when the sensor reading is determined not to include sensor drift. The sensor drift is removed when the sensor reading is determined to include sensor drift.

Abstract: A method that includes obtaining a sensor reading from a sensor installed inside an underground vault and determining whether the sensor reading is indicative of an alarm state. When the sensor reading is indicative of the alarm state, the method obtains at least one new reading and determines whether the sensor reading includes sensor drift based at least in part on the at least one new reading. The alarm state is established when the sensor reading is determined not to include sensor drift. The sensor drift is removed when the sensor reading is determined to include sensor drift.

Abstract: A system that includes a gas sensor, a fresh air flow controller, a sample flow controller, and a system controller. The fresh air flow controller is configured to deliver fresh air to the gas sensor. The sample flow controller is configured to deliver a sample to the gas sensor. The system controller has a processor connected to memory storing instructions that are executable by the processor. When executed, the instructions cause the processor to determine an intermix ratio of the sample to the fresh air, instruct the fresh air flow controller and the sample flow controller to deliver the fresh air and the sample, respectively, to the gas sensor in accordance with the intermix ratio, and receive a sensor reading from the gas sensor after the fresh air flow controller and the sample flow controller have adjusted the fresh air and the sample, respectively.

Abstract: An assembly for harvesting power from one or more power cables. The assembly includes a current transformer operable to harvest power from the one or more power cables and a controller operable to control an amount of power harvested by the current transformer.

Abstract: A method for rejuvenating a strand-blocked cable having a conductor comprised of a plurality of conductor strands with interstitial volume therebetween blocked by a PIB based mastic, the conductor being surrounded by a polymeric cable insulation. The method comprising installing injection adapters that seal the cable ends of the cable and are usable to inject fluid into the interstitial volume between the conductor strands of the cable; elastically expanding the polymeric cable insulation through the application of pressure to the interstitial volume between the conductor strands of the cable; and injecting at least one injection fluid in which the PIB based mastic is at least partially soluble into the interstitial volume between the conductor strands of the cable. To facilitate elastic deformation of the polymeric cable insulation, the cable may be heated to and maintained at a temperature of T1 above ambient during the injection.

Abstract: A method performed by a system controller and evaluating a manhole event occurring in a duct-manhole system. The method includes estimating a size of the manhole event occurring in the system or estimating relative contributions to a fire of at least two of oxidative decomposition, pyrolysis, plasmatization, and flammable gas accumulation. Optionally, the method may include notifying one or more users and/or altering a rate of atmospheric turnover in the duct-manhole system.

Abstract: A system including an active ventilation device and a system controller. The active ventilation device is installed in an underground vault and generates an exhaust flow from the vault having an exhaust rate. The system controller is configured to determine that a reading received from a selected gas sensor indicates that a manhole event is occurring, and instruct the active ventilation device to change the exhaust rate when the reading indicates that the manhole event is occurring. The system controller is configured to receive at least one sensor reading after the exhaust rate has been changed, determine whether the selected gas sensor is exhibiting drift based at least in part on the sensor reading(s), and perform an action when the system controller determines the selected gas sensor is not exhibiting drift. The action includes notifying a user and/or instructing the active ventilation device to alter the exhaust rate.

Abstract: A method performed by a system controller and estimating a size of a manhole event occurring in a network of manhole vaults interconnected by connections. The method includes obtaining first, second, and third mass flow rates for each of a plurality of gaseous components present in exhaust, fresh air, and event flows, respectively, and estimating the size based on the third mass flow rate obtained for at least one of the gaseous components. The exhaust flow exits a selected vault of the manhole vaults, the fresh air flow enters the selected vault from an external atmosphere, and the event flow originates from the manhole event. The third mass flow rate for each of a portion of the gaseous components is determined by subtracting the second mass flow rate obtained for the gaseous component from the first mass flow rate obtained for the gaseous component.

Abstract: A system for use with a connection comprising a terminus opening into an underground vault. The system includes a perturbation detector and a system controller. The perturbation detector is configured to detect values of each of one or more properties and transmit a signal encoding the values to the system controller. The system controller is configured to receive the signal, use at least one of the values to determine whether a fire is occurring or has occurred, and alert a user when the system controller determines that the fire is occurring or has occurred.

Abstract: A tank including a fluid reservoir, a communication module, a controller, and at least one sensor. The fluid reservoir is configured to be in fluid communication with a cable segment. The communication module is configured to communicate with an external device. The sensor is configured to detect an injection parameter value, encode the injection parameter value in a sensor signal, and send the sensor signal to the controller. The controller is configured to automatically instruct the communication module to transmit information to the external device based on the injection parameter value.

Abstract: A tank including a fluid reservoir, a communication module, a controller, and at least one sensor. The fluid reservoir is configured to be in fluid communication with a cable segment. The communication module is configured to communicate with an external device. The sensor is configured to detect an injection parameter value, encode the injection parameter value in a sensor signal, and send the sensor signal to the controller. The controller is configured to automatically instruct the communication module to transmit information to the external device based on the injection parameter value.

Abstract: A system for use with a connection comprising a terminus opening into an underground vault. The system includes a perturbation detector and a system controller. The perturbation detector is configured to detect values of each of one or more properties and transmit a signal encoding the values to the system controller. The system controller is configured to receive the signal, use at least one of the values to determine whether a fire is occurring or has occurred, and alert a user when the system controller determines that the fire is occurring or has occurred.

Abstract: A system including an active ventilation device and a system controller. The active ventilation device is installed in an underground vault and generates an exhaust flow from the vault having an exhaust rate. The system controller is configured to determine that a reading received from a selected gas sensor indicates that a manhole event is occurring, and instruct the active ventilation device to change the exhaust rate when the reading indicates that the manhole event is occurring. The system controller is configured to receive at least one sensor reading after the exhaust rate has been changed, determine whether the selected gas sensor is exhibiting drift based at least in part on the sensor reading(s), and perform an action when the system controller determines the selected gas sensor is not exhibiting drift. The action includes notifying a user and/or instructing the active ventilation device to alter the exhaust rate.

Abstract: A method performed by a system controller and estimating a size of a manhole event occurring in a network of manhole vaults interconnected by connections. The method includes obtaining first, second, and third mass flow rates for each of a plurality of gaseous components present in exhaust, fresh air, and event flows, respectively, and estimating the size based on the third mass flow rate obtained for at least one of the gaseous components. The exhaust flow exits a selected vault of the manhole vaults, the fresh air flow enters the selected vault from an external atmosphere, and the event flow originates from the manhole event. The third mass flow rate for each of a portion of the gaseous components is determined by subtracting the second mass flow rate obtained for the gaseous component from the first mass flow rate obtained for the gaseous component.