The VENTURA 20NKBN-25-TD-U3 is an aircraft nickel-cadmium battery used in onboard 24 V DC electrical systems.It is intended for autonomous engine start,APU start,emergency power supply,and ground operation when the main power sources are not available.The battery works as part of the aircraft DC

　　The VENTURA 20NKBN-25-TD-U3 is an aircraft nickel-cadmium battery used in onboard 24 V DC electrical systems.It is intended for autonomous engine start,APU start,emergency power supply,and ground operation when the main power sources are not available.The battery works as part of the aircraft DC network together with battery contactors,protection devices,charging circuits,busbars,and cockpit indication.It is not a converter or voltage regulator.Its job is to store electrical energy and deliver high current when the aircraft system requires it.

　　Starting and emergency power through 20NKBN-25-TD-U3

　　In service,the battery can supply high current for starter loads and support selected DC consumers in emergency modes.This is especially important before generators come online or when external power is not connected.The battery may be used for starting main engines or auxiliary power units,depending on the aircraft electrical design.Actual starting capability depends not only on the battery type,but also on charge condition,temperature,wiring resistance,contactor condition,and the load connected to the DC bus.

　　Marking structure of the 20NKBN-25-TD-U3 battery

　　The designation gives the basic battery type."20"refers to the number of cells connected in series."NK"identifies the nickel-cadmium electrochemical system."B"means battery,while"N"refers to the pasted electrode design."25"indicates the nominal capacity class."TD"means the battery includes a thermal sensor for overheating indication."U3"refers to the climatic version.This marking is important during procurement because similar aviation batteries may have the same voltage class but different capacity,thermal control,dimensions,or operating limits.

　　Aircraft application of battery 20NKBN-25-TD-U3

　　The 20NKBN-25-TD-U3 is used on aircraft and helicopters where this battery type is specified by the electrical system documentation.Typical applications include An-74,An-140,Il-62,Il-76,Il-86,Il-96,Tu-154,Tu-204,Mi-8MTV,Mi-171,and Ka-32 configurations.The exact installation should still be checked by aircraft documentation,because battery compartment layout,connector arrangement,charging system settings,and thermal indication wiring may differ by aircraft type,production series,or modification standard.

　　The 20NKBN-25-TD-U3 is used on aircraft and helicopters where this battery type is specified by the electrical system documentation.Typical applications include An-74,An-140,Il-62,Il-76,Il-86,Il-96,Tu-154,Tu-204,Mi-8MTV,Mi-171,and Ka-32 configurations.The exact installation should still be checked by aircraft documentation,because battery compartment layout,connector arrangement,charging system settings,and thermal indication wiring may differ by aircraft type,production series,or modification standard.

　　Technical details

　　Product Type

　　Aircraft nickel-cadmium battery

　　Function

　　Autonomous engine/APU start,emergency and ground DC power supply

　　Application/Where Used

　　Aircraft and helicopter onboard DC electrical systems

　　System/Installation Area

　　Battery compartment/24 V DC onboard network

　　Compatible Aircraft/Equipment

　　An-74,An-140,Il-62,Il-76,Il-86,Il-96,Tu-154,Tu-204,Mi-8MTV,Mi-171,Ka-32,subject to aircraft documentation

　　Collapse specifications

　　Battery Type

　　Nickel-cadmium aircraft battery with pasted electrodes

　　Number of Cells

　　20

　　Nominal Voltage

　　24.0 V

　　Nominal Capacity

　　25.0 Ah

　　Continuous Discharge Current

　　Up to 250 A

　　Starter Load Discharge Current Amplitude

　　Up to 650 A

　　Temperature Range for Charge and Discharge Characteristics

　　−20 to+50°C

　　Operating Temperature Range with Performance Maintained

　　−60 to+60°C

　　Vibration Resistance

　　10–2000 Hz,10 g

　　Impact Resistance

　　12 g,2–20 ms

　　Thermal Sensor

　　TD version,overheating signal above approx.+60…+70°C

　　Weight With Electrolyte

　　Not more than 25 kg

　　Dimensions

　　392×175.5×229 mm

　　Charge Retention

　　30 days

　　Warranty Period in Cold and Temperate Climate

　　5 years

　　Warranty Period in Tropical Climate

　　3 years

　　Service Life in Tropical Climate

　　Not less than 3 years

　　Technical Documentation

　　Battery passport/aircraft battery maintenance documentation

       VENTURA AERO