Object Crossing Zones A-B vs AB

[bob2000]

Hi,

Can anyone explain the difference between zone crossing triggers; AB and A-B ?

From the manual:

(1) "AB Object must have entered both zones A and B, overlapping or not

When two zone letters are used together, this is an and condition. The object must have existed in both zones (not necessary simultaneously)"

(2) "A-B Object must travel between zones A and B in either direction"

It seems to me that AB; and object in A and B although not simultaneously is the same as an object that moves from A>B or B>A ?

Is this something to do with the center of the object boxes instead of the box overlap?

It's a bit confusing, can anyone explain the difference.

thanks a lot!

[Thixotropic]

I'd love to hear someone that understands this explain it because it's a bit confusing to me too.

For example, is there a time period in which these events must occur? Is there a "cool down" time that applies, after which the initial trigger is reset, or...??

For example, in the "A-B" scenario, could an object exist in zone A for an hour, and then cross into zone B without triggering, or will it happen no matter what?

Or, in the "AB" (no dash) scenario, does BI 'remember' something as previously being in one of the two, non-overlapping zones? So if I step into zone A, and then exit the area and enter zone B from another direction and NOT crossing the zones, will BI 'recognize' me from when I was in zone A?

For example, I have a cam viewing the back of the house (zone A) and one in front (zone B).
I step into zone A, then I leave zone A and walk around the house, and enter zone B. Does that cause a trigger?

[MikeBwca]

Hi,

Can anyone explain the difference between zone crossing triggers; AB and A-B ?
...

Essentially, your correct. AB would be about the same as A-B or A>B, A<B

However, lets say you have a third zone... C. They are lined up, A B C left to right. AB-C would mean that motion would need to be detected in both A & B zones, then trigger when crossing to C (and vice vera). This is different than A-B, B-C. Lets say you only want a trigger when crossing from B to C, BUT, there's a lot of shadow movement in the B zone causing lots of false triggers when the shadow moved between B & C zones.

AB-C would reduce/eliminate those false triggers by requiring motion to be in both A & B, before triggering to C. This would work if the shadow movement does appear in zone A.

Or, Am I talking nonsense? lol

[MikeBwca]

...
For example, is there a time period in which these events must occur? Is there a "cool down" time that applies, after which the initial trigger is reset, or...??

Yes, Make Time & Break Time.

For example, in the "A-B" scenario, could an object exist in zone A for an hour, and then cross into zone B without triggering, or will it happen no matter what?

Again, Make Time & Break time.

Or, in the "AB" (no dash) scenario, does BI 'remember' something as previously being in one of the two, non-overlapping zones? So if I step into zone A, and then exit the area and enter zone B from another direction and NOT crossing the zones, will BI 'recognize' me from when I was in zone A?

I don't think so. But, if you include another zone that includes zones A & B, then yes (I think), if it also meets the Make & Break times. The extra connecting zone does not have to be in any other setting.