- ampere-conductors
- ampere-hour
- ampere-minute
- ampere-voltmeter
- amplification coefficient
- amplify
- analogue computer
- antennas
- anti-creep
- antiferroeletric
- antifreeze liquid
- AND circuit
- anderson bridge
- Andreau generator
- anemometer
- aneroid barometer
- anisotropic conductivity
- annular conductor
- anode drop
- antihunt device
- antiinterference
- antinode
- antiphase nucleus
- aperiodic
- aperiodic ammeter
- aperiodic galvanometer
- aperture
- apparent defect
- apparent viscosity
- approach light
- arc
- arcing contacts
- arcing shield
- armature head
- armature winding
- armoured cable
- artificial ageing
- asbestos insulation
- ash cooler
- askarel
- assurance factor
- asymmetrical load
- athermic
- atmospheric condenser
- arc baffle
- arc chute
- armored cable
- armored switch
- armature oscillator
- asbestos braid
- ash collector
- assembling
- artificial loading
- ash silo
- astatic galvanometer
- asynchronous machine
- athermanous
- atmospheric electricity
- atomic number
- atomic structure
- arc back
- arc discharge
- arc drop
- arc splitter
- arc welding
- area moment
- armature reaction
- armour
- arrester
- artificial neutral
- ash analysis
- aspect ratio
- astatic system
- atmospheric discharge
- atomic lighthouse
- attention device
- attenuation
- attenuator
- attractive electromagnet
- audiometer
- auger
- aural
- automated equipment
- audio
- audion
- authoritative test
- auto-disconnect
- autoconnected transformer
- autoexcitation
- automatic reclosure
- autonomous
- auxiliary contacts
- auxiliary transformer
- availability factor
- available
- average power
- autopsy
- autotransformer
- auxiliary contact
- auxiliary voltage