Do Most Panels Change Their Circuit Polarity?

[james.wilson]

ive look at an old 9800 manual

It doesnt mention anywhere about circuits changing polarity

It does have individual tampers. Id assume from the panels we use and know that they wouldnt change.

Im not saying it doesnt but i cant see the benefit of having it.

[IAS]

but i cant see the benefit of having it.

before your time (and god forbid it`s Arfurs domain) - panic buttons used to be open circuit. For some reason it was a reg that they were negative bias.

forgot why I asked now LOL

[james.wilson]

was it?

You can still use open circuits with conditions. But i dont know any reg that stipulates polarity. Id suggest that was because panels didnt have PA inputs in those days and it was to cause a tamper?

But once they were closed circuits and you could detect short circuits that wouldnt be relevant anymore.

How sure are you that these things invert (ie lets stay with the 9800 for now). Its not a panel i use or know so i havnt a clue. Id just be surprised due to the complexity required on the board to achieve this.

[IAS]

was it?

How sure are you that these things invert (ie lets stay with the 9800 for now). Its not a panel i use or know so i havnt a clue. Id just be surprised due to the complexity required on the board to achieve this.

pretty sure but we are trying to remember something from 1986 (last time I read a manual) seem to remember it been when proggramable zones became the norm.

honestly it isn`t worth worrying about.

[arfur mo]

Dunno tbo, always do fsl.

Will play on tommorows install.

why not simply phone the tech line?

claiming that linking the 24 hour zone loop to another zone + loop (conventional) prevents setting, is not proof it inverts that 24 hour zone loop to a negative. not saying it don't stop setting but this may be a glitch or 'intelligent' software that causes this.

the earlier G591 could swap the universal tamper to become zone 9 if you programmed zones for EOL (a highly useful trick now dropped) , but that made the tamper zone EOL instead of a loop circuit.

Arfur

[alterEGO]

pretty sure but we are trying to remember something from 1986 (last time I read a manual) seem to remember it been when proggramable zones became the norm.

honestly it isn`t worth worrying about.

9651?

[arfur mo]

before your time (and god forbid it`s Arfurs domain) - panic buttons used to be open circuit. For some reason it was a reg that they were negative bias.

forgot why I asked now LOL

FYI -:

yes they were commonly O/C, as were earlier door contacts and pressure matts,

brings up an annolomy, Chubbs bought Rely-a-Bell and Burgots to get into this game, RAB used hand made 'kerry springs' as door contacts which were closed circuit and o te leading edge, where as Burgots (who i initially trained with - so i do know as fact ) were later on the alarm scene and used O/C contacts in the door jams, when i joined they were changing over to CC contacts but again located in the door jam.

about 2 years after i started all door contacts were CC, and if spotted on a service we had t swap them out

but a REG it had to be - bias?

no, your confused here. the reason they would be on the negative is simple convenience

pab's were not often indicated or zoned separately, so where specified they would be wired into the -VE loop of a zone as that was the 'anti tamper' loop, only on later mains panels was made '24 hour tamper', but that pair would then be wired into a dedicated PA termination, or you installed a relay.

old Panics were O/C because most early systems were totally battery operated, running a Closed Circuit PAB would mean more drain on the panel batteries, or you had to have another circuit added with its own EOL batteries.

multizone panels were the exception back then, usually it was one zone with toggle switches as isolators, so you had to be 'on you game' to sort out false alarms 1st visit in those days , a soundly by the service manager rollocked if you didn't.

Arfur

[hpotter]

Dunno tbo, always do fsl.

Will play on tommorows install.

no it wont.

Had a play & it dont.

What 'every other' panel does this paul? None of the mainstream panels change their polarity, its a hardware thing

try this - take a 9800 and short a panic zone and a normal 12hr zone - see if it sets, it won`t (polarity changed) 959, 9651 - take your pick. Should have said "like every other proper panel does" I suppose.

If you prog scanny ENxx zone as 24hr, then it does become opposite polarity to eg pa or na zone. (can also mix fsl, fsl with various res values or dble pole on different zones.

[IAS]

Had a play & it dont.

If you prog scanny ENxx zone as 24hr, then it does become opposite polarity to eg pa or na zone. (can also mix fsl, fsl with various res values or dble pole on different zones.

is that a yes or a no them?

[hpotter]

if tis set as 24hr, does it not invert same as every other panel does?

no the 9651 does not.

yes the EN85/95 does