# sensors ## Description An array of sensor objects that make up the fan enclosure object. The sensors are what's monitored to determine the functional state of the fan. A sensor's functional range is determined by the following equation(where *[target]* is current requested target of the fan): * Minimum = ([target] * (100 - [`deviation`](deviation.md)) / 100) * `factor` + `offset` * Maximum = ([target] * (100 + [`deviation`](deviation.md)) / 100) * `factor` + `offset` Therefore, a fan sensor must be above the minimum and less than the maximum to be deemed functional. ## Attribute Value(s) * `name` - string * The name of the fan tach sensors located under the `/xyz/openbmc_project/sensors/fan_tach` D-Bus path. * `has_target` - boolean * Whether this sensor D-Bus object contains the `Target` property or not. * `target_interface` - string (Optional) * The D-Bus interface containing the `Target` property. This defaults to `xyz.openbmc_project.Control.FanSpeed` for RPM controlled fans or can be set to `xyz.openbmc_project.Control.FanPwm` for PWM controlled fans. * `target_path` - string (Optional) * The D-Bus full object path containing the `Target` property. This defaults to `/xyz/openbmc_project/sensors/fan_tach`+`name`. * `factor` - double (Optional) * A value to multiply the current target by to adjust the monitoring of this sensor due to how the hardware works. This sensor attribute is optional and defaults to 1.0. * `offset` - integer (Optional) * A value to shift the current target by to adjust the monitoring of this sensor due to how the hardware works. This sensors attribute is optional and defaults to 0. ## Example
{
"fans": [
{
"inventory": "/system/chassis/motherboard/fan0",
"allowed_out_of_range_time": 30,
"functional_delay": 5,
"deviation": 15,
"num_sensors_nonfunc_for_fan_nonfunc": 1,
"monitor_start_delay": 30,
"fan_missing_error_delay": 20,
"nonfunc_rotor_error_delay": 0,
"sensors": [
{
"name": "fan0_0",
"has_target": true,
"target_interface": "xyz.openbmc_project.Control.FanPwm",
"target_path": "/xyz/openbmc_project/control/fanpwm/PWM0"
},
{
"name": "fan0_1",
"has_target": false,
"factor": 1.45,
"offset": -909
}
]
}
]
}