Abstract: A method for use with an underground network that includes a plurality of locations. The method includes receiving sensor data from at least one sensor located at a first of the plurality of locations and determining the sensor data indicates that a fire is in progress. The method includes identifying one or more of the locations as one or more potential combustion locations and assigning an estimate of a probability to each of the potential combustion location(s). The estimate estimates a likelihood that the potential combustion location is an actual combustion source. The method may include displaying the estimate of the probability assigned to each of the one or more potential combustion locations.

Abstract: A system including a processor and sensor for installation inside an underground vault. The sensor monitors a parameter inside the vault and sends a monitoring signal to the processor. Based on the monitoring signal, the processor may provide data to a memory for storage and/or control signals to an interface for transmission to an external device located within the vault. The control signals instruct the external device to modify the environment inside the vault. The sensor may be positioned inside an enclosure, which is inside a housing. An air moving device moves air into or out of the enclosure thereby drawing air from the vault into the enclosure before the sensor monitors the parameter. A heat generating component may be positioned inside the housing and when generating heat prevents moisture from condensing therein. The system may include a power unit that draws power from a power source inside the vault.

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: 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 for use with a manhole vault having an internal atmosphere, and, optionally, with a ventilation stack connecting the vault to an external atmosphere. The system includes a manhole cover, a ventilation pipe, and an air moving assembly. The cover has one or more through-holes extending between top and bottom surfaces. Each of the through-hole(s) is in fluid communication with the external atmosphere at the top surface. The pipe has a through-channel that extends between first and second openings. The first opening is positioned proximal to either an opening into the ventilation stack or at least one of the through-hole(s) at the bottom surface of the cover. The second opening is positioned in the interior of the vault. The device is configured to cause a portion of one of the interior and external atmospheres to flow through the through-channel toward a different one of the interior and external atmospheres.

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 manhole vault having an internal atmosphere, and, optionally, with a ventilation stack connecting the vault to an external atmosphere. The system includes a manhole cover, a ventilation pipe, and an air moving assembly. The cover has one or more through-holes extending between top and bottom surfaces. Each of the through-hole(s) is in fluid communication with the external atmosphere at the top surface. The pipe has a through-channel that extends between first and second openings. The first opening is positioned proximal to either an opening into the ventilation stack or at least one of the through-hole(s) at the bottom surface of the cover. The second opening is positioned in the interior of the vault. The device is configured to cause a portion of one of the interior and external atmospheres to flow through the through-channel toward a different one of the interior and external atmospheres.

Abstract: A system for circulating air inside a manhole vault. The system includes an air-moving device in fluid communication with the manhole vault and configured to circulate the air inside the manhole vault to prevent a concentration of combustible gasses or to enhance cooling therein.

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 flow restrictor for installation in a connection having a terminus opening into an underground vault. The flow restrictor includes an annular restriction device and a concentration member. The annular restriction device is configured to be installed in the annulus near the terminus opening and to restrict a flow of one or more gases through the annulus of the connection. The concentration member is configured to concentrate the flow and includes a through-channel configured to allow the concentrated flow to flow between the underground vault and the annulus.

Abstract: A cable accessory for injecting fluid into a cable. The accessory has first and second ends configured to be coupled to the cable and an external cable accessory, respectively. The accessory has an injection port configured to introduce the fluid to a stranded conductor of the cable. The accessory may include a body and conductive rod. The body defines a through-channel configured to receive the conductor. The rod has a first portion that extends outwardly from the second end to be received inside the external cable accessory and to form an electrical connection therewith. The rod has a second portion configured to be coupled to the conductor and form an electrical connection therewith. The second portion (with the conductor coupled thereto) is positionable inside the through-channel with the first portion extending outward from the second end. The fluid is injectable into the conductor through injection port, which extends into the through-channel.

Abstract: A cable accessory for injecting fluid into a cable. The accessory has first and second ends configured to be coupled to the cable and an external cable accessory, respectively. The accessory has an injection port configured to introduce the fluid to a stranded conductor of the cable. The accessory may include a body and conductive rod. The body defines a through-channel configured to receive the conductor. The rod has a first portion that extends outwardly from the second end to be received inside the external cable accessory and to form an electrical connection therewith. The rod has a second portion configured to be coupled to the conductor and form an electrical connection therewith. The second portion (with the conductor coupled thereto) is positionable inside the through-channel with the first portion extending outward from the second end. The fluid is injectable into the conductor through injection port, which extends into the through-channel.

Abstract: A fitting for injecting a first fluid into an injection port of a cable accessory. The fitting includes at least one seal positioned on an injection nozzle. The nozzle is configured to be inserted into the port and has an internal fluid passageway through which the first fluid is injected into the accessory. The seal forms at least one fluid tight seal between the nozzle and the port. The fluid tight seal prevents the first fluid from exiting the accessory and flowing into an outer portion of the port and prevents a second fluid from flowing into an inner portion of the port. The first and second fluids have first and second voltage potentials, respectively. The second voltage potential is different from the first voltage potential. The seal isolates the first and second voltage potentials by isolating the first fluid from the second fluid.

Abstract: A valve assembly that includes a valve body, a poppet member, and a biasing member. The valve body has an internal through-channel. The poppet member has an inside portion positioned at least partially inside the through-channel and an outside portion positioned outside the through-channel and extending outwardly beyond the valve body. The poppet member is movable within the through-channel between an open position and a closed position. The biasing member is external to the valve housing and applies a biasing force to the outside portion of the poppet member that biases the poppet member toward the closed position.

Abstract: An insert for constructing a cable accessory used to inject a fluid into a cable. The cable accessory has an outer body defining an interior configured to house a conductor of the cable. The outer body includes an injection port with an internal channel configured to receive the fluid. The insert has first and second portions. The first portion is configured to line a portion of the interior of the cable accessory. The first portion has a first through-channel configured to allow the conductor of the cable to pass at least partway therethrough. The second portion is configured to line the internal channel of the injection port. The second portion has a second through-channel in fluid communication with the first through-channel. The insert is less permeable to the fluid than the outer body of the cable accessory. The insert may be molded into the outer body.

Abstract: A high-pressure connector for use with a cable accessory having an injection port with an opening into an interior chamber defined by one or more sidewalls. The connector includes a body portion and one or more fluid seals. The body portion has an inner fluid chamber, an outer surface, and an aperture. The inner fluid chamber is configured to allow a conductor of a cable to pass therethrough. The fluid seal(s) are positionable between the outer surface of the body portion and the one or more sidewalls to define an outer fluid chamber. The outer fluid chamber is positioned such that the opening of the injection port is positioned within the outer fluid chamber so that a fluid exiting the injection port through the opening enters the outer fluid chamber. The aperture connects the outer and inner fluid chambers and allows the fluid to flow therebetween.

Abstract: An injection protocol for a cable includes selecting a cable for testing, selecting a pre-injection electrical discharge test for determining if electrical discharge activity occurs at or about operating voltage of the cable, configuring the cable for the pre-injection electrical discharge test; running the pre-injection electrical discharge test on the cable, and determining whether to inject the cable with a restorative fluid based upon electrical discharge activity detected at or about operating voltage of the cable.

Abstract: A method for enhancing the dielectric properties of an electrical cable segment having a central stranded conductor encased in a polymeric insulation jacket and an interstitial void volume in the region of the conductor, including filling the interstitial void volume with a dielectric property-enhancing fluid at a pressure below the elastic limit of the polymeric insulation jacket, and confining the fluid within the interstitial void volume at a residual pressure greater than about 50 psig, with the pressure being imposed along the entire length of the segment but below the elastic limit of the polymeric insulation jacket. Preferably, the residual pressure is sufficient to expand the interstitial void volume along the entire length of the cable segment by at least 5%.