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+# zones.json
+
+Zones are groups of fans that are set to the same values and have the same
+properties like `default_floor` and `poweron_target`.  The events in
+[events.json](events.md) are then configured to operate on specific or all
+zones.
+
+## JSON Example
+
+```
+{
+  "name": "0",
+  "poweron_target": 18000,
+  "default_floor": 18000,
+  "increase_delay": 5,
+  "decrease_interval": 30
+}
+```
+
+## Attributes
+
+### name
+The zone name.  Required.
+
+### poweron_target
+The fan target value set immediately after the power state changes to on.
+This is also the ceiling unless `default_ceiling` is specified.  Required.
+
+### default_floor
+The default fan floor value to use for the zone, if necessary.  Possibly an
+action will be configured to be in charge of the floor so this isn't
+necessary.  Optional.
+
+### increase_delay
+This throttles fan increases to the specified delay.
+
+The delay, in seconds, between fan target increases, when an action such as
+NetTargetIncrease requests an increase.  All increases requested
+inside of this interval are analyzed and if the highest requested target is
+greater than the current target, this new target is set when the delay expires.
+
+Some actions may set the fan target directly, such as one that increases the
+target when a fan is removed, and this does not apply then.
+
+Optional with a default of zero, meaning increases are immediately requested.
+
+### decrease_interval
+This throttles fan decreases to the specified delay.
+
+The delay, in seconds, between fan target decreases, when an action such as
+NetTargetDecrease requests a decrease.  All increases and decreases requested
+inside of this interval are analyzed and if the highest requested target is
+lower than the current target, this new target is set when the delay expires.
+
+Optional with a default of zero, meaning decreases are immediately requested.
+
+### default_ceiling
+The ceiling of the zone, i.e. the highest target that can be set.
+
+This is optional and if not specified it defaults to the `poweron_target`
+value.