This version of the API shipped with Indigo 6.1.5 - check the API Version Chart to see what version of the API is available in which Indigo versions.
ownerProps to the base Device class that is a shortcut to the owning plugin's (the plugin that created the device) globalProps dictionary data.multiplierVarId to the SprinklerAction class which specifies the elem ID for the optional variable multiplier. Will be None if no variable multiplier is specified.