PIR logic

Hi All,

Just wanted some advice. I have a load of the basic 360 deg internal pirs (and a couple of external ones come to think of it) and wanted some help with the logic.

I am trying to avoid having to fiddle with the light adjust screws on them all and do that another way. I have both a PAC and a outdoor light sensor.

At the moment the PIRS day/night/sunset programming is the same. Recall 1 (to allow dimming to 30%) then retrigger timer to turn off after 5 mins. I also have a (unique per PIR) disable group set up which gets triggered by the local DLT so the PIR doesn't dim the lights when someone has just turned them to full. An all off from the DLT resets the disable group and allows the PIR to function.

All this works very well except the lights come on in the day!

The only solution I can think of is to have the PAC send out (say every minute) an On to the PIR disable groups in the day time and similarly send a single off when it gets dark ? I presume the PAC can access sunset / sunrise ?

I must admit I don't know how the sunset sunrise thing works on the pir - maybve that would do it.

I am very keen not to have to rely on the the light adjusting screw to get the behaivour right though.

Any ideas / help much appreciated.

Oh and for the first time last night we really / really apreciated just how cool cbus is. We have about a 100 channels and 20 odd DLTs working fantatically well together. Its all nolw very nicely programmed providing gorgeous mood lighting at all times of the day. Cool!!!

Ta
Chris

 

Chris

The light adjusting screw is exactly intended for this kind of job.

If the Key Functions are all per default and the light level is below the threshold, as set by the adjustment screw, then the PIR's will turn on the Group when they detect movement and then run a timer. You can change the Onkey function to Recall 1 @ 30% to get your desired lighting level without affecting this behaviour.

If the light level is above the threshold when movement is detected then the PIR will not turn the Group on. It will however re-initialise the timer every time it detects movement so that the load stays on if it is already on.

If you replace 360 degree PIR's with Multisensors then you can set the Threshold from the Toolkit software but the other PIR products will require you to adjust the threshold via the adjusting screw.

The Sunset function allows you to perform a function when the ambient light level drops below the level as set by the adjusting screw, like run a timer for a few hours to turn on some garden lights etc.

Sounds to me like you're nearly there, just need to check your Day time programming settings and set the light adjusting screw so that the PIR's don't turn the Groups on during the day.

 

I was really trying to avoid using the screw as its a long painful process to adjust 9 of them.

Think I will at least try some PAC code based on time of day / sunset - sunrise times.

I will have 9 lockout groups (one for each PIR) controlled by the PAC based on sunset/sunrise/lightlevel that are used to enable/disable the PIRs as usual.

There will be 9 sub-lockout groups that can be enabled/disabled by local DLTs to stop the PIRs overiding them at night (e.g when someone is having a bath - the bath "mood scene" will turn the sub-lockout on until the mood-scene is switched off).

The PAC will "OR" the lockout and sublockout to turn enavble/disable the PIRs . If it checks the OR every minute that should be sufficient.

Would something like that work? I would prbably use sunset - 2hrs and sunrise +1 hr or something for the period during which the PIRs will be allowed to function.

Chris