9.11 Circadian Curves via the Portal
9.11.1 Introduction
Circadian curves are 24-hour cycles that a human’s body follows as part of its regular daily operation. In terms of lighting, this can mean gradually changing the colour temperature of a luminaire between warmer and cooler outputs throughout the day.
Circadian curves via the Response Portal aim to better align the lighting conditions with a human’s internal body clock. Done by enabling users to create 24-hour schedules of colour temperature and light intensity. Thereby creating a more natural environment indoors which enables alertness during the daytime and helps calm closer to sunset.
9.11.1.1. How to Enable
You can enable the Circadian Curves for your building if you have administrator access to the roles menu. If you don’t have access contact your administrator to enable the permission for your role. If you have permission follow the steps below,
Navigate to building administration page.
Check the option “Circadian Curve“ for the specific role that you want to enable circadian curve for.
Log out and log back and you will see an icon for circadian curve appear next to building administration icon.
9.11.2 Pre-requisites
It is important to realise here that circadian curves are a step further in tunable white technology and hence have same requirements as those that are required for tunable white in Organic Response System. You would require the following to be fulfilled for both nodes and installation,
DT8 drivers
Compatible PIC firmware version (v184 or higher)
Response Portal connected installation
It is recommended that you revisit tunable white chapter by clicking here in order to see more details on whether you installation support tunable white.
While circadian curve would also be applicable on DT6 devices if tagged, they would simply follow dim value changes as these devices do not support color change.
9.11.3. How It Works
The way circadian curve works in Organic Response System is through simultaneous changes in colour temperature and light output of tunable white luminaires. When a user applies a desired curve through the Response Portal the Response Nodes for the whole building or floor will adjust its current colour temperature & light output based upon current time of the Response Portal and its timezone. See some keys steps and considerations before we delve into the how we use the curve,
The curves are sent through the Response Portal to the Response Nodes either to
the whole building or
to a whole floor or
Selected tags including tenant tags and standard tags.
When a curve is sent through the Response Portal it is sent to all the Response Nodes, however, it will only be implemented by the Response Nodes that have the required firmware version.
The Response Nodes check every minute and make adjustments according to the values on the curve.
A curve is only sent as a whole to the Response Node. The Response Node will, based upon the time it is sent from the Response Portal, calculate where it needs to be in the curve over the period of 24 hours.
Upon storing the curve received from the Response Portal the Response Nodes will continue to follow that unless someone disables the curve or sends another curve to override the currently saved curve.
9.11.3.1 Order of Priority
As a result of recent release the curves are now following the order of priority based upon their place in the hierarchy. The curve at the top will have higher priority than the curve lower than itself.
Operational Example: As an example shown above “Standard Curve” (curve 1) will take precedence over “Floor Curve“ (curve 2). The way it will operate is as below,
Curve 1 or higher curve if have tags specified e.g. “Meeting Room“ in the above example all Response Nodes with that tag will follow curve 1.
Curve 2 or lower curve will be applied for the remaining Response Nodes on specified level. From example above all the remaining Response Nodes other that the tag specified in the higher curve will be the only ones that will follow the second curve.
The above example can give you an insight into use cases where multiple curves are created for the same floors and building or some common areas. If multiple curves are specified for the same tags and floors, the Response Portal will ignore all lower curves and will only apply the first curve if they are conflicting curves for the same set of Response Nodes.
Please note that the higher the schedule, the higher the priority. If you set up a building-wide schedule at the top, all the lower schedules will be ignored. See the steps explained below in heading 9.11.4.5 on adjusting a curve's priority.
No Longer Applicable: Due to the above implementation, a floor-level curve will no longer take precedence over the building-wide curve.
It is also recommended to not enable daylight dimming for nodes which are meant to follow Circadian Curve. Since they both offer different automation, thus affecting the behavior of sensor nodes. It can result in unwanted behavior
9.11.4 How to Deploy
In order to understand how you can use Circardian Curves, let's go through a process detailed below, along with the key concepts and logic explained throughout. In order to access the circadian curve menu, first navigate to the Response Portal (click here to access the Response Portal). If Circadian Curves have been enabled for your building and account, you will notice that a new icon is appearing in the Response Portal, as highlighted below,
The circadian curves are only deployed through the Response Portal, which requires mapping all tunable white Response Nodes in the Response Portal prior to setting up curves.
Once you have navigated to the page, you will see that the window is empty, with a message saying “No circadian curve found.”
9.11.4.1 Create a Circadian Curve
Once in the page click on the blue icon on top left corner saying “+ Create new circadian curve“.
A “standard curve“ with default colour temperature and light levels will appear.
Here, you can change
The curve name
You can choose the relevant tag; it could be a tenant tag or a standard tag.
The floors where it will be applied (leave blank if you want the curve to be applied to the whole building)
The colour temperature and maximum light level that will be applied throughout the 24-hour period
As building admin you can only choose one tenant tag in a curve. When a tenant tag is selected, all other tenant tags will disappear. This is done to allow individual curve control for each tenancy.
To ensure security a building admin can’t see/choose tenant created tags. (click here to read more)
As building admin you can view, edit, delete and re-rank the curves which are created by tenants. In doing so you can also delete any curves for tenant created tags as shown below.
The standard curve 3 in the above image is created by the tenant by choosing tenant created tag called ‘Testing tenant krish’. As a building manager, you can still edit/delete that tag and curve. Head over to “being a tenant“ if you are manager of your tenancy.
Let's now have a look at both setting the colour temperature and max light level curves for the Response Nodes separately below. Although it would be important to note that at each given hour the Response Nodes will take both colour temperature and light output levels simultaneously.
9.11.4.2 Setting colour Temperature Curve
A colour temperature curve is displayed in the form of a graph with time in hours shown on an X-axis against colour temperature values (in Kelvin) on the Y-axis. The numbers on the X-axis represent hours of the day, with 0 representing midnight and 23 representing 11pm.
The curve can be edited easily by clicking on a dot that appears for all hours, starting from “0“ and going up to “23“ and dragging it vertically to choose the desired colour temperature for the hour. The increments are made vertically in ~100 kelvin each step up or down. See an example of a colour temperature curve that appears as a standard curve.
The highlighted circle above shows a dot that you can click and drag. As an example, the dot indicates that your desired colour temperature for when the time reaches 07 am is approx. 6000 Kelvin. If this curve is applied, then the colour temperature will transition as below,
From the start of the day until 5 am, it will take the warm colour, for example 2700K from the above figure
From 5 am onwards, the tunable white luminaires will start to get cooler with colour temperature ramping up until it reaches 4000K at 6 am.
From 6 am, it will continue to ramp up to cooler white colour with colour temperature reaching 6000K at 7 am.
From 7 am the lights will start to get warmer with colour temperature that reaches a little over 5000K so on and so forth throughout the day.
A few important mentions here,
The colour temperature values taken by the luminaire are entirely dependent upon the capability of driver to set the temperature values.
If the driver doesn’t support the exact value set by the curve the luminaire will take the closest round off value to set the colour temperature.
If you hover your mouse over any dot it will show the current temperature value as a pop up along with the hour.
9.11.4.3 Setting Max Light Level Curve
A light level curve is functionally similar to colour temperature curve with the curve representing light levels in percentages over the same period of 24 hours as the colour temperature curve. See the example below,
It’s important to remember that light levels from a curve can change the maximum light level that a luminaire can reach. Upon presence detection the light level that luminaire will produce will take the value which is lower out of maxlight or the light level set by curve at any particular time. A couple of example to help explain this better,
If the maxlight level configured for a Response Node is 50% and the curve sets the value to 80% then the Response Node will take 50% light output upon detecting presence.
If the maxlight is 80% and the curve sets dim to 50% then the light output will be 50% upon detecting presence.
If no presence is detected under the Response Node then it will either be at minlight, or in a state of waiting to go to minlight. At any particular time upon presence detection the dim levels set by the curve is limited between the maxlight and minlight value.
Here you can see the light levels are shown on Y-axis and X-axis representing the time in hours. The highlighted circle above shows an example of the dot that you can drag vertically. Here the resolution of each step change is 10% for change in light output values. To understand the transition,
From the start of the day till 5 am the light levels will be set to reach 20% until 5 am
From 5 am to 6 am the light will continue to ramp up with light output level reaching 80% at 6 am.
From here on the light stays at 80% until 5 pm at which point it starts to ramp down, so on and so forth
9.11.4.4 Applying A Curve
Once you are happy with the desired configuration you can use the green button to save the curve. Upon saving a curve the editing window will shrink such that it will now show you both curves,
The first curve from the left is a representation of rising and falling in the colour temperature.
Second curve is a representation of rising and fall in the light output level.
In addition a dot will appear is both curves which is representative of the current time and where the colour temperature and light output values should be.
Another useful indication will be the text shown at the the bottom of the curve to indicate what the current desired values are for colour temperature and light output.
Once you are happy with the curve hover your mouse over the “Play button“ highlighted in the above snapshot and click “Play“. As soon as you click play the name banner of the curve will turn blue to indicate that a curve is applied.
9.11.4.5. Setting Priority of the Curve
When you create a curve they will automatically follow the order in which they are created. In order to adjust or to increase or decrease their priority you can use the up/down arrow as shown in the figure below,
Hover your mouse over the play or pause option as it currently shows next to a newly create curve
Press up to increase the priority of the curve which will shift up one spot
Press the down arrow to reduce the priority of the curve that will shift the curve down one spot.
Once you are happy with the priority click on "Save rank changes" to save the new priority of curve.
9.11.5 Events and Maintenance
9.11.5.1 What happens in Background
In the examples provided above when you press play and as indicated by the dots the following actions will take place,
The complete curves for both colour temperature and light output will be broadcasted through the gateways to your relevant selection e.g. floor, tags, tenancy or the whole building.
For example, if a floor is selected the message will be sent to all the nodes to their individual addresses on the floor through all the gateways in that building.
All nodes that have supported firmware will store the curve and take current desired value as representative of the dot displayed on the curve.
The curve once sent will automatically be estimated by the nodes to ramp up or down dynamically to reach target values indicated with the next arriving hour on the last sent curve.
9.11.5.3 Maintenance
Now a few notes on maintenance of curves,
A curve is only sent at the time of playing the curve while the nodes that have received the curve will continue to make adjustments automatically throughout the day
If you edit an active curve you will need to save it again, however, you do not need to pause and play the curve again.
Please note that when you edit an active curve and save it a pop up will appear as shown below
It is important to understand that granular schedules such as those on a floor take precedence over the building wide schedule so always remember to check the correct schedule when trying to establish the correct colour and light values.
If you wish for the nodes to stop following a curve press on the pause icon that appears as you take your mouse over the play button.
As soon as you click on pause the nodes will go back to the default operation mode based upon their configured parameters.
The nodes can stay in the last received curve for 2 hours after a disable curve command is issued from the Response Portal
It is important to note that you can’t delete a curve without pausing it first. This is so that you don’t lose the current curve sent to the nodes without first clearing it for the nodes to stop following.
Transition across next day - The nodes depending upon variations between the last hour of the day i.e. “23” and start of the day i.e. “0”. The luminaires will ramp up or down from the colour temperature and light output values at hour “23” to reach the values set at “0“.
9.11.5.4 How Does Occupancy Work with Circadian Curve
The occupancy information sensed by the Response Nodes will work as it does in “auto” operation. A circadian curve based control is checked by the Response Nodes periodically, however, in order for the nodes to implement the nodes have to be triggered by occupancy. This is so that the Response Nodes can stay off or at their configured min-light output in the absence of any occupants in the space. As soon as the Response nodes detect occupancy they will start exhibiting the colour temperature and light output based on the current time of the day in the curve.
9.11.5.5 Manual override
If the Response Nodes are overridden by a manual control the Response Nodes will implement the control as they would in normal operating condition i.e. the newly implemented temporary control will take precedence.
As an example, if someone implements a scene on the Response Node that is supposed to follow a curve through a switch or app. The scene will be implemented immediately to the Response Nodes until it naturally exits a scene e.g. if in default configuration the nodes will exit the scene on absence.
9.11.5.6 Curve Query and Change Frequency
Once a curve is sent to the Response Nodes through the Response Portal, the curves are actually stored on the Response Nodes. However, the Response Nodes send a query message every hour to the gateway to get details of the curve and the current time. Since the response nodes are not equipped with any time clock, they will need to obtain the time information from the gateway through this curve query. The frequency of the curve is different depending on the current state of the Response Nodes,
On Response Node startup, if the circadian curve is enabled, the curve would be queried once every 15 minutes for an hour or until a curve is received.
If no curve is received after the first hour, a query from the node will be sent every hour.
When a curve is received, the node should wait 1.5 hours to query the curve and then query every hour until a curve is received. And when the curve is received, it will repeat this
Once the nodes have received the curve message from the gateway and stored it locally, they will check and decide whether to take the next step change every minute.
An example of this would be if, by the next hour, the light output needs to change from 0% to 100%, the nodes will distribute and calculate locally as time goes by to make step changes every minute.
9.11.5.7 Mapping Nodes after a Curve is Applied
Circadian Curves will only be applied to mapped Response Nodes, therefore please make sure that all mapping is completed before activating a curve.
If a Response Node needs to be mapped to a building after a Circadian Curve has been applied, then that Node or Nodes will not receive and begin to use the intended curve. To make sure that the active curve is applied to newly mapped or re-mapped nodes, please deactivate the curve and then activate it again after all mapping is completed.
9.11.5.8 Disabling the Curve
When a curve is disabled, the current firmware will take up to 2 hours before the Response Node will stop following the previously configured curve changes. This means that it will continue to follow the changes as preset by the curve for up to 2 hours after the curve has been disabled before it can revert to its auto-operation mode.