SBH

Searching for a complete solution (PLC+SCADA) for "calendar controlled outputs" for building automation

8 posts in this topic

Hi guys,

I just got involved in a small and simple building automation project. (A small mall, in which they are replacing an older system)

It is simple, yet there is a caveat:
There are about 100 digital outputs (Lights, HVAC...) that should be controlled "calendrically".
Moreover, the operation hours could be dependent on sunrise / sunset time.

For example:
1. Light Floor1East should be activated 30 minutes after sunrise each day of the week, except Fridays and Saturdays in which it should be activated at 05:00AM fixed, excluding July & August.
2. Light Floor2West should be activated at 10:00 AM, each day of the week, except on Holidays (the exact holidays dates are preconfigured by the operator)
3. Light Floor3North should be activated at 12:00 AM on Tuesdays, recurring 10 times. (e.g. over period of 10 weeks) starting from specified date (dd/MM/YYYY)
* Please note that I didn't bother to detail the turn-off times, but you obviously got the idea even without it.

The actual programming of each output is going to be performed be the end user (i.e. the operator) and will be modified from time to time according to the changing needs of the facility.
Hence this programming should be simple and intuitive to accomplish by the operator and performed via the main UI.
(Adding in Edit: Subsequently, such "schedule programming" done by the operator should not require the presence of a "development license key")

For example, if there is a set of outputs that works according to a common schedule, it makes sense for the operator to be able to program them together, as a group.

And on top of all that - there is a separate system requirement:
That the actual programs (output scheduling) will reside in the PLCs so that the system will work continuously in the event of a power failure or any other PC failure.
(This implies that the PLCs should internally maintain and track the calendar, including daylight saving and sunset/sunrise time)
 

Although I searched a lot I could not find any system with matching capabilities.
Except for Siemens WinCC / Calendar Scheduler which seems to be relevant, but I could not tell for sure just from reading the datasheet.

I admit this lacking of "calendar controlled IO module" was surprising to me especially in light of the recent flourishing ecosystem in the Home Automation field.
Note: budget is not a concern, but an open source based solution would gain my sincere admiration. (-;

Any hint would be highly appreciated!

Many thanks!

Edited by SBH
Better wording (hopefully...)

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The Schneider Ecostruxure architecture should be able to do what you're looking for, only problem being it's a closed architecture that only their distributors really know and in my experience they're hesitant train end users.

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There are stand-alone single circuit calendar timers that operate on sunset/sunrise that are intended for lighting purposes.  The one I saw fit in electrical wall box.  I saw the electrician messing with the configuration.  It came in a retail box with printing on it.  Sorry, I didn't catch a name, brand or model and since I didn't buy it, I don't its cost.  But maybe the cost of loal timer control would be offset by the extensive wiring needed to do central control. 

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18 hours ago, BobLfoot said:

The Schneider Ecostruxure architecture should be able to do what you're looking for, only problem being it's a closed architecture that only their distributors really know and in my experience they're hesitant train end users.

Thanks @BobLfoot 

I looked a little at the publicly available information about Schneider Ecostruxure architecture that you've mentioned.
As you anticipated, I could not find details elaborating on the "calendar controlled outputs" issue that I am interested in.

Following your input I also found out that Schneider's Citect has a "Time Schedule Add-On".
From inspecting the Time Scheduler Add On documentation however, it was still hard to figure out whether or not this Add On hits the spot.
(For example, lacking sunrise/sunset time would be a significant shortcoming and I could not find any reference to that)

Maybe I should ask:
Would you say it would make sense to post a follow-up question in this forum about the capabilities of Citect Time Schedule Add On?

Meanwhile I am trying to contact Schneider's local distributor to get some details + a demo.

Many thanks again!

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7 hours ago, DanW said:

There are stand-alone single circuit calendar timers that operate on sunset/sunrise that are intended for lighting purposes.  The one I saw fit in electrical wall box.  I saw the electrician messing with the configuration.  It came in a retail box with printing on it.  Sorry, I didn't catch a name, brand or model and since I didn't buy it, I don't its cost.  But maybe the cost of loal timer control would be offset by the extensive wiring needed to do central control. 

Thanks @DanW
The system I am talking about must have a central Command & Control interface.
As mentioned, we're replacing an existing old centralized SCADA system.
And the customer would not settle for anything less than what he is already accustomed to. (and rightfully so)
A lot of the existing wiring from the old system will be reused - so the cost tradeoff justification you mentioned does not hold.

But really, I find it hard to believe there are no "out of the box" software solutions for controlling outputs according to sunrise/sunset time.
You would have to know your geographic location (which for a building is hard coded... so just use your cellphone GPS once) access a relevant web service, specify the relevant geo-location + date, and obtain the time.

Thanks again!

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Some PLC brands keep their internal time in UTC and can synchronize to GPS time devices (AB Logix processors with a Time Machines TM2000B make a good combination).  Knowing UTC and Lat/Long, sunrise and sunset are pure trigonometry.  I don't know of an out-of-the-box solution, but I wouldn't be afraid to make a custom one.  For the right $$, of course.

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33 minutes ago, pturmel said:

Some PLC brands keep their internal time in UTC and can synchronize to GPS time devices (AB Logix processors with a Time Machines TM2000B make a good combination).  Knowing UTC and Lat/Long, sunrise and sunset are pure trigonometry.  I don't know of an out-of-the-box solution, but I wouldn't be afraid to make a custom one.  For the right $$, of course.

Thanks @pturmel
I would emphasize that the requirement here is being able to fully integrate the sunrise / sunset time in the schedule programming of the outputs, not merely calculating this time.
(Please see the original post which includes some concrete scenarios)

Many thanks!

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14 hours ago, SBH said:

not merely calculating this time.

Details.  On a relative scale of difficulty, I would rank the trig as "more difficult" than setting up data types for your desired on-off schedule rules.  Those are just structured data with some logic to compare the elements against various aspects of the current time.  True geeks would call it a "Domain Specific Language" implemented in ladder logic.

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