AIRCRAFT ELECTRICS VARIABLES

The tables below indicate the properties for the Simulation Variables that can be used to get and set variables related to the electrical system of the aircraft. For information on the units listed for each variable, please see here: Simulation Variable Units

NOTE: When Microsoft Flight Simulator 2024 is running in multiplayer mode, only a small number of variables are communicated between aircraft. Those variables that are available will say so in the description as being either for "All Aircraft" or for "Shared Cockpit".

You can find a complete index of all available SimVars here: SimVar Index

 

The SimVars below are all related to the aircraft electrical system (including lights). Large parts of this system are setup using the [ELECTRICAL] section of the system.cfg file, and many may also require the use of the different to retrieve and edit their values.

 

 

General / Buses

Simulation Variable Description Units Settable
BUS LOOKUP INDEX

This is a settable simvar meaning that it can both be read and set. Some of the simvars in this list are using this to lookup a value using two arguments (one argument in addition to the component index). For example to check the state of the connection between a "circuit.45" and the "bus.2" it would be written as follows:

2 (>A:BUS LOOKUP INDEX, Number) (A:CIRCUIT CONNECTION ON:45, Bool)

It should be notes that when BUS LOOKUP INDEX is not set (ie: it is 0) then TRUE will be returned if any of your bus connections are on.

-
BUS BREAKER PULLED This will be true if the bus breaker is pulled. Requires a BUS LOOKUP INDEX and a Bus name (or index). Bool
BUS CONNECTION ON This will be true if the bus is connected. Requires a BUS LOOKUP INDEX and a Bus name (or index). Bool
ELECTRICAL BUS AMPS:name Retrieve the amperage of the named (or indexed) Bus. Amperes
ELECTRICAL BUS VOLTAGE:name Retrieve the voltage of the named (or indexed) Bus. Volts
ELECTRICAL TOTAL LOAD AMPS Total load amps Amperes
NEW ELECTRICAL SYSTEM Is the aircraft using the new Electrical System or the legacy FSX one. Bool
ELECTRICAL AVIONICS BUS AMPS

Avionics bus current

Obsolete, do not use! Use ELECTRICAL BUS AMPS.

Amperes
ELECTRICAL AVIONICS BUS VOLTAGE

Avionics bus voltage

Obsolete, do not use! Use ELECTRICAL BUS VOLTAGE.

Volts
ELECTRICAL BATTERY BUS AMPS

Battery bus current

Obsolete, do not use! Use ELECTRICAL BUS AMPS.

Amperes
ELECTRICAL BATTERY BUS VOLTAGE

Battery bus voltage

Obsolete, do not use! Use ELECTRICAL BUS VOLTAGE.

Volts
ELECTRICAL GENALT LOAD

This returns the percentage of the load output that is being consumed. This requires an alternator index when referencing.

Obsolete, do not use!

Percent
ELECTRICAL GENALT BUS AMPS

The load handled by the alternator. This requires an alternator index when referencing.

Obsolete, do not use! Use ELECTRICAL BUS AMPS.

Amperes
ELECTRICAL GENALT BUS VOLTAGE

General alternator voltage. This requires an alternator index when referencing.

Obsolete, do not use! Use ELECTRICAL BUS VOLTAGE.

Volts
ELECTRICAL MAIN BUS AMPS

Main main named (or indexed) Bus current.

Obsolete, do not use! Use ELECTRICAL BUS AMPS.

Amperes
ELECTRICAL MAIN BUS VOLTAGE

The main named (or indexed) Bus voltage.

Obsolete, do not use! Use ELECTRICAL BUS VOLTAGE.

Volts
ELECTRICAL OLD CHARGING AMPS

Obsolete, do not use! Use ELECTRICAL BATTERY LOAD.

Amps

 

 

Batteries

Simulation Variable Description Units Settable
BATTERY BREAKER PULLED This will be true if the battery breaker is pulled. Requires a BUS LOOKUP INDEX and a Battery name (or index). Bool
BATTERY CONNECTION ON This will be true if the battery is connected. Requires a BUS LOOKUP INDEX and a Battery name (or index). Bool
ELECTRICAL BATTERY ESTIMATED CAPACITY PCT The given Battery capacity over max capacity, 100 is full. Percent
ELECTRICAL BATTERY LOAD:name The load handled by the named (or indexed) Battery, where negative values mean the battery is receiving current. Amperes
ELECTRICAL BATTERY VOLTAGE:name

The named (or indexed) Battery voltage.

Volts
ELECTRICAL HOT BATTERY BUS AMPS Current available when the battery switch is turned off Amperes
ELECTRICAL HOT BATTERY BUS VOLTAGE Voltage available when the battery switch is turned off Volts
ELECTRICAL MASTER BATTERY:name The named (or indexed) Battery switch position, true if the switch is ON. Bool

 

 

Breakers

Simulation Variable Description Units Settable
BREAKER ADF*

All these SimVars can be used to get or set the breaker state for the electrical system (either true or false).

If the breaker is popped (set to false), then the associated circuit will not receive electricity.

  1. * these are Convenience SimVars
Bool
BREAKER ALTFLD* Bool
BREAKER AUTOPILOT Bool
BREAKER AVNBUS1* Bool
BREAKER AVNBUS2* Bool
BREAKER AVNFAN* Bool
BREAKER FLAP Bool
BREAKER GPS* Bool
BREAKER INST* Bool
BREAKER INSTLTS* Bool

BREAKER LTS PWR*

Bool
BREAKER NAVCOM1 Bool
BREAKER NAVCOM2 Bool
BREAKER NAVCOM3 Bool
BREAKER NAVCOM4 Bool
BREAKER TURNCOORD* Bool
BREAKER WARN* Bool
BREAKER XPNDR* Bool

 

 

Circuits

Is electrical power available the signal inside the plane to indicate we are not yet ready to carry on with the activity (skydive, airdrop...)

Simulation Variable Description Units Settable
ELECTRICAL CIRCUIT EXISTS:name This can be used to find out if any circuit of the given type is present in the aircraft electrical system. Unlike other SimVars in this section, the index here is not a specific circuit, but rather the index of the circuit type as listed here: Circuit Types Bool
ELECTRICAL CIRCUIT AMPS:name This indicates the load being consumed (in amps) by the named (or indexed) Circuit. Amps
ELECTRICAL CIRCUIT VOLTAGE:name This indicates the tension intake (in volts) by the named (or indexed) Circuit. Volts
CIRCUIT AUTOPILOT ON Is electrical power available to this circuit or not. Bool
CIRCUIT AUTO BRAKES ON Is electrical power available to this circuit or not. Bool
CIRCUIT AUTO FEATHER ON

Is electrical power available to this circuit. Please see the for more information.

Bool
CIRCUIT AVIONICS ON Is electrical power available to the avionics circuit or not. Bool
CIRCUIT BREAKER PULLED:bus:name This will be true if the circuit breaker is pulled. Requires a BUS LOOKUP INDEX and a Circuit name (or index). Bool
CIRCUIT CABIN SIGNAL GO Is electrical power available the to signal inside the plane to indicate to carry on with the activity (skydive, airdrop...) or not. Bool
CIRCUIT CABIN SIGNAL STANDBY Is electrical power available the signal inside the plane to indicate to get ready and stand by until we are ready to carry on with the activity (skydive, airdrop...) Bool
CIRCUIT CABIN SIGNAL STOP Is electrical power to the signal inside the plane to indicate whether an activity can be performed (skydive, airdrop...) stopped or not. Bool
CIRCUIT_COM_ON Is electrical power available to the COM circuitor not. Bool
CIRCUIT CONNECTION ON:bus:name

This will be true if the circuit is connected. Requires a BUS LOOKUP INDEX and a Circuit name (or index).

Bool
CIRCUIT ELECTRIC ENGINE ON Is electrical power available to the electric engine circuit Bool
CIRCUIT FLAP MOTOR ON Is electrical power available to the flap motor circuitor not. Bool
CIRCUIT GEAR MOTOR ON Is electrical power available to the gear motor circuitor not. Bool
CIRCUIT GEAR WARNING ON Is electrical power available to gear warning circuitor not. Bool
CIRCUIT GENERAL PANEL ON Is electrical power available to the general panel circuitor not. Bool
CIRCUIT HOIST ON Is electrical power available to the hoist circuit or not. Bool
CIRCUIT HYDRAULIC PUMP ON Is electrical power available to the hydraulic pump circuit or not. Bool
CIRCUIT HYDRAULIC VALVE ON Is electrical power available to the hydraulic valve circuit or not. Bool
CIRCUIT MARKER BEACON ON Is electrical power available to the marker beacon circuit or not. Bool
CIRCUIT NAV ON Is electrical power available to the NAV circuit or not. Bool
CIRCUIT NAVCOM1 ON Whether or not power is available to the NAVCOM1 circuit or not. Bool
CIRCUIT NAVCOM2 ON Whether or not power is available to the NAVCOM2 circuit or not. Bool
CIRCUIT NAVCOM3 ON Whether or not power is available to the NAVCOM3 circuit or not. Bool
CIRCUIT NAVCOM4 ON Whether or not power is available to the NAVCOM4 circuit or not. Bool
CIRCUIT ON:name This will be true if the given circuit is functioning. Use a Circuit name (or index) when referencing. Bool
CIRCUIT PITOT HEAT ON Is electrical power available to the pitot heat circuit or not. Bool
CIRCUIT POWER SETTING:name This returns the percentage of use that the circuit is getting. This requires a Circuit name (or index) when referencing. Percent
CIRCUIT PROP SYNC ON Is electrical power available to the propeller sync circuit or not. Bool
CIRCUIT ROTOR BRAKE ON Is electrical power available to the rotor braking circuit or not. Bool
CIRCUIT SLING ON Is electrical power available to the sling circuit or not. Bool
CIRCUIT STALL WARNING ON Is electrical power available to stall warning circuit or not. Bool
CIRCUIT STANDBY VACUUM ON Is electrical power available to the vacuum circuit or not. Bool
CIRCUIT SWITCH ON:name The circuit switch position, true if the switch is ON. Use a Circuit name (or index) when referencing. Bool
CIRCUIT TRANSPONDER ON Is electrical power available to the transponder or not. Bool

 

 

Generators

Simulation Variable Description Units Settable
ELECTRICAL GENERATOR ACTIVE:name This indicates whether or not the named (or indexed) Generator is outputing tension. Bool
ELECTRICAL GENERATOR AMPS:name This indicates the load being drawn (in amps) by the named (or indexed) Generator. Amps
ELECTRICAL GENERATOR VOLTAGE:name This indicates the tension output (in volts) by the named (or indexed) Generator. Volts
ELECTRICAL GENERATOR SWITCH:name This can be used to either retrieve whether the named (or indexed) Generator is currently switched on or not, or it can be used set whether the generator is on or off. Bool

 

 

External Power

Simulation Variable Description Units Settable
ELECTRICAL EXTERNAL POWER AMPS:name This indicates the load being drawn (in amps) by the named (or indexed) ExternalPower source. Amps
ELECTRICAL EXTERNAL POWER VOLTAGE:name This indicates the tension output (in volts) by the named (or indexed) ExternalPower source. Volts
EXTERNAL POWER AVAILABLE:name This will be true if the the named (or indexed) ExternalPower source is available. Bool
EXTERNAL POWER BREAKER PULLED:name The state of the breaker of the named (or indexed) ExternalPower source. Bool
EXTERNAL POWER CONNECTION ON:name The state of the connection between a bus and the named (or indexed) ExternalPower source. Bool
EXTERNAL POWER ON:name The named (or indexed) ExternalPower source switch position, true if the switch is ON. Bool

 

 

Lines

Simulation Variable Description Units Settable
ELECTRICAL LINE CONNECTION ON:name The current status of the named (or indexed) Line connection, either 1 (TRUE) for on, or 0 (FALSE) for off. Bool
ELECTRICAL LINE BREAKER PULLED:name Bool
LINE CONNECTION ON:name The current status of the named (or indexed) Line connection, either 1 (TRUE) for on, or 0 (FALSE) for off. Bool
LINE BREAKER PULLED:name The current status of the named (or indexed) Line breaker, either 1 (TRUE) for pulled, or 0 (FALSE) for not pulled. Bool

 

 

Alternators

IMPORTANT! These SimVars are only useful when working with the v1.00 electrical system. See here for more information: LEGACY: systems.cfg - [ELECTRICAL]

Simulation Variable Description Units Settable
ALTERNATOR BREAKER PULLED This will be true if the alternator breaker is pulled. Requires a BUS LOOKUP INDEX and an alternator index. Bool
ALTERNATOR CONNECTION ON This will be true if the alternator is connected. Requires a BUS LOOKUP INDEX and an alternator index. Bool
GENERAL ENG MASTER ALTERNATOR:index The alternator (generator) switch position, true if the switch is ON. Requires an engine index, and the use of an alternator index when referencing. Bool

 

 

APU

IMPORTANT! These SimVars are only useful when working with the v1.00 electrical system. See here for more information: LEGACY: systems.cfg - [ELECTRICAL]

Simulation Variable Description Units Settable
APU BLEED PRESSURE RECEIVED BY ENGINE Bleed air pressure received by the engine from the APU. Pounds per square inch (psi)
APU GENERATOR ACTIVE:index Set or get whether an APU is active (true) or not (false). Takes an index to be able to have multiple generators on a single APU. Bool
APU GENERATOR SWITCH:index

Enables or disables the APU for an engine. Takes an index to be able to have multiple generators on a single APU

Bool
APU ON FIRE DETECTED Will return true if the APU is on fire, or false otherwise. Bool
APU PCT RPM Auxiliary power unit RPM, as a percentage Percent Over 100
APU PCT STARTER Auxiliary power unit starter, as a percentage Percent Over 100
APU SWITCH Boolean, whether or not the APU is switched on. Bool
APU VOLTS:index

The volts from the APU to the selected engine. Takes an index to be able to have multiple generators on a single APU.

Volts
BLEED AIR APU Boolean, returns whether or not the APU attempts to provide Bleed Air. Bool