Standalone Motion sensors

Hi friends!

I was dealing with a customer site where I found a standalone sensor '753'(360 dg Indoor PIR) installed in the toilet.
There I came to know that it's not an occupancy sensor but a motion sensor which triggers the load when movement is detected.
Now customer wants an occupancy sensor with standalone feature. There is no way that I can break the false ceiling and run a CAT5 through it.

Is there any way to come out?

Can I increase sensetivity of the sensor so that it can apparntly behave like an occupancy sensor? How?

 

PIR "??" detector

Hi Manas
Assuming you are not playing on the pun, They tend to be call occupancy detectors / sensors because motions in locations you mention refer are a different thing altogether......
Both the C-Bus & Stand alone versions use the same principles of operation so changing it will make little difference. Often PIR's are poorly placed or commissioned leading to in-effective operation.
First understand the principle of operation, that the PIR detects heat movement (relevant to ambient) moving from one of it's detection segments to another. Therefore it will detect grose body movement (not minor movement, such as typing or wiping) in it's direct line of sight, between it's segments.
Second, once it has "detected" something moving it uses a timer to keep the load on for the preset period of time.
If a PIR is installed in a toilet airlock it will detect and turn on the lights when a person enters and will turn off when the timer period expires. It has no idea of what someone may be doing on the otherside of the door. Likewise if it is installed in the toilet area it cannot detect in the stalls.
Check the location & settings of your PIR to get it working properly, Classic pitfalls are:
1, Location, is it right? is there line of sight? will movement typical of the area be across the detection area? (see the instructions for a detection pattern picture)
2, Day/Night setting? check that for an internal application that it is set to detect in Day & Night conditions (When lights are on & off)
3, Timer setting? Clipsal 751 & 753 PIR's have a maximum timer period of 20 minutes and it is a log scale, not linear. (if they need more than 20 minutes in a stall they have serious problems, beyond the capabilities of the PIR!). Worst case turn up the timer, but then this tends to defeat the purpose of the installation (to turn the lights off) as when a person leaves, they retrigger the timer to start again.
Changing it to a C-Bus one will give you more possibilities, but if it's not appropriately installed to start with it will not make a difference!
We installed over 150 of them in toilets on a campus, placement is critical.
Cheers
Matthew

 

Thanks Matthew.

Actually, the little difference in C-Bus and Standalone feature is the "Programming of Long Press and long releasr", which makes that sensor occupancy detector.

Anyways, I checked the location. It is perfect. No issue regarding detection. It's working ok with increase in timer value... But it defeats the purpose of energy saving. It doesn't detect minor body moves.

Thanks for your reply!

 

I am still trying to understand the difference between a presence sensor and motion sensor...but anyway, I think you mean the standalone 753 is not sensitive enough and the light goes off even when there is a person with little movement in range...

With the cost to think about any C-Bus sensor (if it is not a C-Bus site), it would be better to go for the standalone Dual Tech Sensor, i.e. PIR+Ultrasonic sensor. There are more options using the dip switch and all you need is to hide the transformer inside the false ceiling and install the new sensor. Well, they look different and it is much bigger but doing a much better job....

BTW, I am not very good at programming C-Bus sensor. How does the programming of "long press and Long release" help in C-Bus sensor?

 

I am also confused about motion and presence sensor definition. Anyway, I have seen them working differrent, practically.

Motion sensor will require 'considerable' movement to rettrigger the timer.
Presence sensor continuously detects the person and will remain triggered.

For Short Press, trigger the lighting group.
(i.e. Momentary thermal emission detected by sensor)
For short release, program the sensor to remain ideal
(i.e. Momentary absence of thermal emission)
For long press, 'trigger the light group.'
(i.e. Long presence of thermal body. This is where, I think, occupancy sensors are different)
For long release, call the 'off' function for resp. lighting group.
(i.e. Long absence of thermal body)
This is how we programmed an occupancy sensor. And It worked well. It practically detects thermal body, without considerable movements required.

 

I think you are very confused Manas. A PIR is a PIR, ie something that detects movement it doesn't detect if a room is occupied per se, it detects movement. Sure you can change the sensitivity to make it more sensitive, but that IIRC is done by the screw on the unit not in software. You may have configured something in software that does what you would like, but that doesn't change the fact that a PIR detects movement. Changing long press/short press settings etc, changes how the load is switched based on the movement detected by the PIR.

There are different types of motion sensors that are more sensitive, ultra sonic as somone else mentioned for example, but Clipsal don't as far as I am aware offer an ultra sonic C-BUS sensor. Even if you did have one as the other poster pointed out it wouldn't work through stalls , you would need one over every cubicle and in the hand basin area.

Now the question is what are you trying to acheive. Others might have a simple and better answer to your problem.

 

Gee, I had to comment on this. A motion detector by any other name is an occupancy detector. As a rule of thumb the timer setting in toilets should be between 8-12 minutes (ie a reasonable time for the task at hand), if the sensor triggers when you first walk in great, adjusting the sensitivity will not do much unless you have a tendancy to move around alot while on the job. Funny how simple things become complicated.

 

[/QUOTE] Funny how simple things become complicated.[/QUOTE]

That's important. As a rule of thumb.. I will now change the timer to 10 min.

 

Funny how simple things become complicated.[/QUOTE]

That's important. As a rule of thumb.. I will now change the timer to 10 min. [/QUOTE]

Maybe it would be simpler if you would say what you want to acheive rather then using mixed up terms.

 

Ashley, I don't think that English is Manas's first language, so cut him some slack, there is no need to have a go at him.