Pir Placement Query

[CarlG]

Hi Guys,

I've about finalised the layout for my new system (Texecom Premier 48) but I'm a bit unsure on best placement for the PIR in the hallway and would be appreciate any views on the possible locations shown in the image.

My current and soon to be removed alarm (B&Q wireless jobbie) has a PIR in position A set with a pulse count of 2 and that's worked perfectly over the last few years but given the location faces the door and side windows I couldn't use a pulse count of 1 without false alarms from the post coming through the letter box. I'm not sure how the sensitivity of the current sensor compares to the Texecom wired units though.

Of the options shown: -

A - Covers all the hall but potential for false alarms

B - No chance of false alarms from the post but leaves the front section of the hall unprotected

C - Less chance of false alarm but it would be located where the ceiling drops and therefore it will give limited coverage of the front section of the hall

D - Covers all of the hall but would post coming through the door cause false alarms given it's going across the path of the sensor?

E - I'm guessing there's less chance of a false alarm but again, is it likely to pick up post coming through the door?

I have a Texecom Prestige Dual Tec PIR for this room and will spend time setting the microwave sensitivity correctly. Also, I'm keen if possible for the PIR to be visible to a certain extent to deter any little ***** looking through the letterbox. The other option (although a bit overkill) would be to put 1 Dual Tec sensor in position A with double knock set and another IR PIR in position B just in case the first didn't trigger, or is that a daft idea?

I'd be very grateful for any thoughts on this.

,

Carl

[hpotter]

A or D will be fine (providing as you say - set up m/w correctly, dont want postie triggering m/w element as he approaches, or might aswell go for a quad)

If your cheapo B&Q job has worked without any probs at A, I cant see why a better Q detector wont do the same.

[james.wilson]

Technically id for D but depends how close to the post you are. Larger items may cause an issue.

But with any movement sensor if you introduce movement you have the potential for a false alarm

James

[CarlG]

Thanks for the responses, A & D seemed like the most likely to me. As an alternative, would a Pet immune PIR be a better bet for position D to get around the post issue?

,

Carl

[james.wilson]

Id say no, as its pet immune not post immune.

In reality if your going to introduce movement of cold items into a warm room then id expect problems. You could adjust your sensor around this, blank out the areas or move the sensor, but without actually seeing it, id struggle to say. I have had issues with post and it does depend on the size of the area, size of post, distance post thrown by postie, distance from sensor and the quality of the sensor. Only way to be sure is to test it. But again you put things in an area that move then its likly a movement detector will alarm..... just as its supposed too.

I have an intellisense DT 7550 above left of my own front door and do not have a problem with post. Cant speak for the texecom sensors as ive never used em.

James

[hpotter]

Pet immune wont make any difference, unless those letters are red hot bills?

As James said, air turbulance can cause issues (if postie dont push the post through eg), but ime on a bog standard letterbox with quality equipment you wont have a problem.

[CarlG]

Pet immune wont make any difference, unless those letters are red hot bills?

Ain't that the truth!

Thanks again for the replies. I can cable fairly easily to both A & D so I'll give them a both a try on soak test and see what happens.

,

Carl