Analogue inputs

[chris_j_hunter]

we've some QAIs around the house, and most have only one or two of their four inputs used (for thermistors) ...

so, wondered if anyone had any ideas for uses for the unused ones ....

an obvious thing to add to them might be a simple potentiometer - to give a variable input, for controlling something ...

eg: for light-dimmer control (single or multiple) - 'though doing that's covered by other means, so there’d be no need !

any thoughts ?

[neilhooper]

Hi Chris,

I don't know if you'd have a use for some extra temperature measurement. I'm thinking of maybe using some Danfoss Randall TS-2's (http://danfoss-randall.co.uk/xxTypex...U17434841.html) for temperature measurement in bathrooms. I've been testing one that we had left over from a recent heating system install and it works perfectly with the standard settings of a QAI. They are quite small, unobtrusive, cheap and widely available. Also, there is a complete absence of anything electronic inside the box apart from the thermistor making them, I think, ideal for humid environments.

- Neil

[Karam]

On the other hand it might be quite useful to measure humidity in a bathroom . A while back there was a person who fitted piezo resistive pressure sensors under the toilet. Don't know how well these worked.

[chris_j_hunter]

>extra temperature measurement ...

we're already doing something like that ... indeed, that's how the situation arose ... ie: our QAIs with three spare channels are the ones we're using to provide Black Bulb temperature readings that augment PLH temperature & humidity sensing in those zones ...

http://www.titanproducts.com/categories/1_134_16/Room_Temperature_Sensor_Black_Bulb.html

[neilhooper]

Chris,

Just a question, are you not using a centralised wiring system? I'm purposely putting most of my Idratek hardware at node 0 and running wiring out to wherever it's needed. It has taken some very careful planning. That way I believe that I'm getting maximum use out of the hardware.

- Neil

[chris_j_hunter]

Hi Neil -

yep, not easy to choose ...

for the electrics, power & signal, and HA, we went fully radial - no rings, no trees !

and for the modules we went for a distributed approach, rather than central ...

our Node0 has the Cortex PC & PCA & IPSs and a number of modules for local functions, and all cables run out radially from it - pretty literally, too ...

a normal house has cables run to well over a hundred different locations, but we thought it through and concentrated everything electrical into something over forty, to help manage complexity & costs - power & signal & HA ...

Node0 is one of those locations, but also has the breakers & patch-panels, too ... apart from the few it made sense to put elsewhere (eg: plant-room) ...

modules in each location are simply daisy-chained together ...

apart from the IPSs, all our DIN-rail modules are in the satellite locations, not Node0 - when we used them, it was generally for compactness and/or compatibility with IP65 enclosure requirements ...

our module-count has inevitably grown along the way, and the distributed approach has made this quite easy to accommodate ...

Chris