System Upgrade - First Issue

[ChipMonk]

FAO hpotter

I've done the sums again in more detail for the entire system I'm planning and it's definitely going to be well over 750mA - so an additional PSU IS called for. I have in mind an RGL 1201EMC PSU to provide an additional 1A capacity, primarily to power the external and internal sounders.

I'd therefore be grateful if you would clarify exactly what you meant by "link the 0v between the two" as I queried in post #19.

For those of you mystified by my references to a Scantronic 5651 Panel above - it should of course be Scantronic 9651. Apologies! Old age is catching up with me.

Once again thanks.

Chip

[djrock]

Hello, No the cqr’s TWM only requires the 1k resistors. It’s the scanny panel that needs the 2k2 resistor for the tamper return.

A few months ago I fitted the cequra and it came with two 1k resistors. I know the cequra has twm on the strobe trigger because the strobe trigger wire came out and the strobe started to flash. I don’t have the install manual for the protecta so can’t say if the strobe has twm. So see if the manual shows it needs one or two 1k resistors.

I agree with IAS, On paper they will draw in sab mode 700ma in total. But in the real world this could be much less.

djrock

[hpotter]

The only way to be certain what the panel draws in full alarm is to meter it - in full alarm (as per commissioning). I agree manufacturers info tends to give exagerated expectations. However, you can get a pretty good idea on paper.

EN panel max 750mA

Panel uses 130mA in standby 220mA max in full alarm - say 175mA

Keypads x 2 will use 60mA (unless you have back lights on permenantly then 140mA) - say 60mA

Digi 75mA in alarm - say 70mA

PIRs say 6 x 10mA (quiscent) = 60mA

Leaves you with 385mA to run sounders/strobes/spkrs.

Allow say 80mA ea for strobes - 160mA

Say 1 spkr @ 40mA

Leaves 185mA to run sounders.

Possible in SCB mode. But not how I'd fit it tbo.

If you prefer SAB (louder of course & I assume this is what you prefer hence 2 sounders?), then I would power them from a seperate psu using a couple of relays on op1 & 2. You can still sort the trigger wire monitoring by using 1k resistors in psu but you would need to bring the tamper wire back to the TR terminal in the panel via the 2k2 resistor as posted before.

In doing the above you will need to reference the two supplies by connecting the 0v of the panel to the 0v of the psu.

[ChipMonk]

Family bereavement has caused a drastic change in priorities. I'll provide some feedback at a later date.

Many thanks for all contributions in answer to my many questions.

Chip