Internally, OVMS raises events whenever significant events occur. An event is simply a name, along with associated data. Individual vehicle types may also issue their own events, and custom user events are also possible. Here is the list of standard system events in the OVMS v3 firmware:

Event Data Purpose
sd.mounted   The SD card is mounted and ready to use
sd.unmounting   The SD card is currently unmounting
sd.unmounted   The SD card has completed unmounting
sd.insert   The SD card has just been inserted
sd.remove   The SD card has just been removed
location.enter.<name> <name> The specified geolocation has been entered
location.leave.<name> <name> The specified geolcation has been left
gps.lock.acquired   GPS lock has been acquired
gps.lock.lost   GPS lock has been lost
system.wifi.down   WiFi connection has been lost
app.connected   One or more remote Apps have connected
app.disconnected   No remote Apps are currently connected
server.v2.waitnetwork   V2 server connection is waiting for network
server.v2.connectwait   V2 server is pausing before connection
server.v2.connecting   V2 server connection in progress
server.v2.authenticating   V2 server connection is authenticating
server.v2.connected   V2 server connection established online
server.v2.disconnected   V2 server connection has been lost
server.v2.waitreconnect   V2 server is pausing before re-connection
server.v2.stopped   V2 server has been stopped
server.v3.waitnetwork   V3 server connection is waiting for network
server.v3.connectwait   V3 server is pausing before connection
server.v3.connecting   V3 server connection in progress
server.v3.authenticating   V3 server connection is authenticating
server.v3.connected   V3 server connection established online
server.v3.disconnected   V3 server connection has been lost
server.v3.waitreconnect   V3 server is pausing before re-connection
server.v3.stopped   V3 server has been stopped
vehicle.require.gps   A vehicle has indicated it requires GPS
vehicle.require.gpstime   A vehicle has indicated it requires GPS time
vehicle.type.set <type> Vehicle module has been loaded
vehicle.type.cleared   Vehicle module has been unloaded
vehicle.alert.12v.on   12V system voltage is below alert threshold   12V system voltage has recovered   VMS volts/temps exceeded thresholds
vehicle.on   Vehicle has been switched on   Vehicle has been switched off
vehicle.awake   Vehicle systems are awake
vehicle.asleep   Vehicle systems are asleep
vehicle.charge.start   Vehicle has started to charge
vehicle.charge.stop   Vehicle has stopped charging
vehicle.charge.prepare   Vehicle is preparing to charge
vehicle.charge.finished   Vehicle charge has completed normally
vehicle.charge.pilot.on   Vehicle charge pilot signal is on   Vehicle charge pilot signal is off
vehicle.charge.12v.start   Vehicle 12V battery is charging
vehicle.charge.12v.stop   Vehicle 12V battery has stopped charging
vehicle.locked   Vehicle has been locked
vehicle.unlocked   Vehicle has been unlocked
vehicle.valet.on   Vehicle valet mode activated   Vehicle valet mode deactivated
vehicle.headlights.on   Vehicle headlights are on   Vehicle headlights are off
vehicle.alarm.on   Vehicle alarm has been armed   Vehicle alarm has been disarmed
vehicle.charge.mode <mode> Vehicle charge mode has been set
vehicle.charge.state <state> Vehicle charge state has changed
system.modem.gotgps   Modem GPS has obtained lock
system.modem.lostgps   Modem GPS has lost lock
system.modem.poweringon   Modem is powering on
system.modem.poweredon   Modem is powered on
system.modem.muxstart   Modem MUX has started
system.modem.netwait   Modem is pausing before starting DATA
system.modem.netstart   Modem is starting DATA network
system.modem.netloss   Modem has lost DATA network
system.modem.nethold   Modem is pausing DATA network
system.modem.netsleep   Modem is sleeping DATA network
system.modem.netdeepsleep   Modem is deep sleeping DATA network
system.modem.stop   Modem has been shut down
system.modem.received.ussd <ussd> A USSD message has been received
network.interface.up   Network connection is established
system.modem.gotip   Modem received IP address from DATA
system.modem.down   Modem has been disconnected
system.shuttingdown   System is shutting down
system.shutdown   System has been shut down
network.wifi.up   WIFI network is up
network.reconfigured   Networking has been reconfigured
network.up   One or more networks are up
network.interface.change   Network interface change detected
network.wifi.down   WIFI network is down
network.down   All networks are down
network.modem.up   Modem network is up
network.modem.down   Modem network is down
network.mgr.init   Network manager has initialised
network.mgr.stop   Network managed has been stopped
config.mounted   Configuration is mounted and available
config.unmounted   Configuration is unmounted and unavailable
config.changed   Configuration has changed
housekeeping.init   Housekeeping has initialised
system.start   System is starting
ticker.1   One second has passed since last ticker
ticker.10   Ten seconds have passed
ticker.60   One minute has passed
ticker.300   Five minutes have passed
ticker.600   Ten minutes have passed
ticker.3600   One hour has passed