A888 Series Control Systems

Alison Control's A888 Series Control Systems, renowned for fire detection and control in a wide variety of industrial environments, are custom-designed to the exact needs of the application and the requirements at the specific site.

The A888 Series Control System is unique because it can monitor the complete spectrum of detection devices and trigger appropriate response actions. Control effectiveness can be designed to range from a relatively simple, single zone analog system to a highly complex, multi-zone microprocessor-controlled system.

Unlike "off-the-shelf" fire detection and control systems, which may not be precisely what is needed for the installation, Alison Control's systems are developed and engineered from the ground up, bringing together technology from a wide range of sources. The engineering takes place only after company experts have had the opportunity to meet with the customer, carefully review what needs to be protected and fully understand all factors related to the specific application and location.

 

9090 Continuous Thermal Sensor

the alison control 9090 series continuous linear thermal sensor is a small-diameter coaxial wire which is capable of sensing temperature changes along its entire length. the sensor is constructed of a center conductor and an outer inconel 625 sheath. the center conductor is electrically insulated from the outer sheath by a ceramic thermistor material.

since the thermistor has a negative coefficient of resistance, this means that the electrical resistance between the center wire and the outer sheath decreases exponentially as the surrounding (ambient) temperature increases.

when connected to the appropriate a888-mxxx control panel, the 9090 sensor can have multiple independent adjustable fixed temperature set points, become a rate of rise detector, identify the location of a hot spot, supply a constant temperature readout during a fire incident and be used as a temperature measuring device for process control.

the sensor has a diameter of approximately 0.085" (2.16mm and therefore has a small mass which permits it to sense changes in temperature rapidly. its response time index (rti) is 58. with proper selection of thermal sensor material, it can sense temperatures from 70º f (21º c) up to 1,200º f (649º c). it can withstand temperature extremes of from -60º f (-51.1º c) to 2,000º f (1,093º c).

the alison control 9090 series thermal sensor should not be confused with fixed-temperature open circuit devices which close only when a predetermined temperature or rate of temperature rise is reached. such open circuit devices-including fixed temperature, rate compensated or rate-of-rise thermostats; fire detecting wire containing a fusible salt; or a pair of twisted insulted steel wires- are not nearly as versatile or reliable.

sensor length

the sensor is manufactured in lengths of 25 and 50 feet (7.6 and 15.24m). shorter lengths are available on special order. longer lengths, up to 1,000 feet (305m), may be assembled from a number of shorter lengths coupled together with hermetically sealed connectors. it is also possible to assemble several lengths having different temperature ranges so that hazards with different ambient temperature or heat conditions can be protected economically with a single length of sensor.

nuclear environments

the 9090 sensor has been exposed to radiation levels as high as 200 megarads and has been certified by an outside testing laboratory to meet the requirements of ieee 323 and 344.

 

High Expansion Foam Systems

High Expansion Foam Movie (1 Meg)    Generator Details (102k)

High Expansion Foam (HEF) by Alison Control Inc. totally extinguishes the two major classes of fire.

Class A Fire paper, wood, cloth, etc., where quenching by water is effective.
Class B Fire gasoline, oils, paints, burning liquids, cooking fats, etc., where smothering action is required.
  • HEF provides total system reliability that insures system operation whenever it is called upon to work... all solid-state supervision makes system totally self-monitoring including motor windings.
  • HEF reduces total site fire protection costs.
  • HEF systems are water-saving systems... they use a minimum amount of water (small volume and very low pressure) to do a maximum job-any water used is used more efficiently.
  • HEF does not destroy product (primarily because of lower water content).
  • HEF does limit smoke damage, and because of the detergent properties of the foaming agent, it provides a self-cleaning effect.
  • HEF, itself, due to its non-corrosive nature, is easy to clean up... leaves no messy, sticking residue.
  • HEF, also, provides a thermal insulating barrier for personnel and product protection.
  • HEF is a volumetric, 3 dimensional fire fighter... it can get around all obstacles and lends itself easily to total flooding or local application.

Application Features

On local application, a couple of feet of HEF will extinguish a 2 dimensional fire.

  • HEF is as effective on alcohol and LNG as it is on hydrocarbons such as gasoline, kerosene, JP-4, etc.
  • HEF can extinguish flaming liquid 3D fires.
  • HEF extinguishes fire as well inside as outside, in subzero or tropical climates, and at high or low altitudes.

Applications

The all new high expansion foam by ACI can be used for truly modern fire protection in warehouses and high rack storage areas, for commodities such as rubber tires, rolled paper, plastics, paints, etc....in bulk storage areas...in conveyor tunnels, coal mines, and diked areas...in electric power plants for protection on gas turbine peak loading stations, coal handling equipment tunnels, auxiliary warehouses, etc... and in aircraft hangars, process plants of all types, and in shipboard use.

The fire hazards posed by Group II Aircraft Hangars are addressed by NFPA 409. The standard defines a Group II hangar as one with an aircraft access door height of 28 feet or less and a single fire area no greater than 40,000 square feet.

The most cost effective and efficient way to protect these hangars is through the installation of a High Expansion Foam (HEF) System as described in chapter 4 of the standard. Despite the fact that Group II hangars are typically located in rural areas with inadequate water supplies to support most types of systems, the water pressure and supply can usually support a HEF system.

In addition to the economic advantages of using less water and foam concentrate, a HEF system offers distinct fire fighting advantages over low expansion foam. Aircraft maintenance hangars are usually cluttered with rolling tool kits, work stands and nested aircraft, making it very difficult for a Low Expansion Foam system to be deployed rapidly. Alison Control's HEF system offers the most efficient way to extinguish fuel spill blazes, the worst potential fire scenario for hangars and their contents.