Hooking up a transformer

grendel54

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I am using a transformer from 120V to 60VA 30a. The load side I would assume is considered class 2. Would I be able to run CAT5 cable on the load side? I am running it in the walls from the Plenum where the transformer will be installed.
 

Teken

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I am using a transformer from 120V to 60VA 30a. The load side I would assume is considered class 2. Would I be able to run CAT5 cable on the load side? I am running it in the walls from the Plenum where the transformer will be installed.
If this cable is running through any air ducts you must use CMP rated wire. Any cable that runs through walls or floors must use CMR.
 
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With that kind of power capability I'd run romex, probably 14 gauge assuming AC, just to be on the safe side. You have a nominal 1800 watt power source there. CAT cable, 23 gauge, would act like a big resistor and easily overheat under dead short conditions. Even if you ran two CAT cables and used all the conductors of each for each side of the output of your transformer I wouldn't be comfortable with it, if it were me.

Looking at the thread area, I assume that you meant to say 30VA not 30A. A very large difference but you'd still need to use multiple conductors to be safe. Nominal wire size for a doorbell is 18 gauge. Why not use some 18/2 thermostat wire and be done with it. You could pull a CAT cable along with it to future proof for a PoE doorbell in the future.
 

grendel54

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30VA is correct. Standard cat5 is 24 gauge. "Doorbell" wire bought at Lowes or home depot is generally 20 or 18 gauge. Just wondering since CAT 5 is so readily available. I have some spare 12Gauge romex laying around but know this is overkill.
 

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If this cable is running through any air ducts you must use CMP rated wire. Any cable that runs through walls or floors must use CMR.
For the record (and I concur with @sebastiantombs on conductor recommendations above), you are correct in stating CMP must be used in plenums or air ducts BUT you can also run CMP where CMR is required but you should not run CMR where CMP is required.
 
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