Strange resistance from contact sensor?

[Mrjollyjoe]

So ive moved and changed alarm panel, not far!


all up and working however im connecting to some agricultural buildings which the old panel was connected to and for the first few days all was well,

there's an expander in there which my old panel connected to so the feed just goes to the new panel,

2 contact and 1 pir, all eol,

1 eol contact has started playing up, i checked in wintex and it was giving weird readings that dance around not stable, i swapped the sensor for a new one (std door contact decent brand) still the same, so as its only a 4m run of cable i even replaced that still the same even swapped channel in the expander still the same! its giving 8.95k resistance when closed in wintex?

all new contacts in house eol giving stable resistance as to be expected

Any ideas what could cause such as issue, it worked fine for years prior, and did work fine for nearly a week upon installing new panel. never encountered anything like it, the pir on the same expander is perfectly stable in wintex and does perfect reading for detection, although the roller shutter contact is a bit fluctuating but works.

 

[secureiam]

What resistor values are you using?
Did you test the cable rather than using wintex to verify?

What’s the power at expander, trying to understand the layout.

 

[Mrjollyjoe]

sorry for late reply i was busy last night,

im using a std setup with i believe 2k2 and 4k4 resistors supplied with texecom (or used to!) units.

ive not tested the voltage at the expander can you see this in wintex?

so alarm>expander 1 with
pir
door sensor (one with wierd resistance
Roller shutter sensor

rest if unused but the date out goes to another expander

i removed it from alarm for now so i don't have to omit it, just been to check it in wintex and the resistance is still floating around, that with a new sensor and new resistors!

 

[secureiam]

Have you measured this with a meter?
How is it wired in the expander?

The roller shutter is the issue, what roller shutter.

There are few different types, some with more than two cables and you have to use them in a certain way to get the right combo.

If your using the resistors as supplied.

4.k7 2k2 and 3.3k were supplied from memory they have supplied any for many years now.

4.k7 4k7 is around 9k.

You say fluctuating between what ?

 

[secureiam]

If you twist the cables together that go directly to the zone what do you get showing back at the panel end (expander end).

If your using 2k2 and 4k7 then you are looking for 2k2 closed door and 6k9 open door.