OK we have wired a house to have 230 volt LED lights but the owner has now changed her mind as she doesn't like the light output, she has now seen some ELV lights she likes, but the only way it can be done is to put 1 transformer for more than 1 light. So can find out volt drop from the BRB for AC voltage but how do you calculate volt drop for DC voltage thanks CJS
DC volt drop
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DC and AC volt drop is calculated in exactly the same way. ohms law applies to both DC and AC
But it will be more of an issue with DC as generally you are talking about low voltage, so the current will be higher, and the tolerable volt drop will be lower.
So unless you are lucky, cables sized for 230V ac lighting are likely to be too small for DC lighting.
But it will be more of an issue with DC as generally you are talking about low voltage, so the current will be higher, and the tolerable volt drop will be lower.
So unless you are lucky, cables sized for 230V ac lighting are likely to be too small for DC lighting.
sparkytim
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Normally you need to keep the 12 Volt wiring to a minimum 1.5 mtrs or so with 1mm
If you wire several fittings from a Torodial Transformer then you can reduce Volt drop by wiring a 2.5mm Ring main type circuit to feed the fittings (Max load to suit transformer rating) I have coverd large reception areas with no problem using this method.
If you wire several fittings from a Torodial Transformer then you can reduce Volt drop by wiring a 2.5mm Ring main type circuit to feed the fittings (Max load to suit transformer rating) I have coverd large reception areas with no problem using this method.
PC Electrics
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Look at the units: mV/A/m
Volt drop is proportional to amps. AC or DC don't matter.
If you're talking 12V DC, then you will get 20x the volt drop of 240V AC as the current is 20x. So your cables need to be larger csa and much shorter.
Volt drop is proportional to amps. AC or DC don't matter.
If you're talking 12V DC, then you will get 20x the volt drop of 240V AC as the current is 20x. So your cables need to be larger csa and much shorter.
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The rule of thumb for low volt fittings is keep the cables a short as possible!!!
some transformers recommend 2m or 3m top's from bulb to tranny.
If you are running multiple bulbs off one transformer, (say 3 for example),
no matter how far away the bulbs are it is good to keep ALL low voltage leads the same length the the volt drop is equal!
or you can have a situation where one bulb looks visibly dimmer than the rest
e.g.
Transformer
bulb#1 0.5m away
bulb#2 1m away
bulb#3 2m away
with some fittings the extra 1.5m between the nearest and the furthest can be visibly dimmer!
so do all leads at 2m keep volt drop and dimming effect the same!
HTH
SL :x
GuinnessGuinnessGuinnessGuinness
some transformers recommend 2m or 3m top's from bulb to tranny.
If you are running multiple bulbs off one transformer, (say 3 for example),
no matter how far away the bulbs are it is good to keep ALL low voltage leads the same length the the volt drop is equal!
or you can have a situation where one bulb looks visibly dimmer than the rest
e.g.
Transformer
bulb#1 0.5m away
bulb#2 1m away
bulb#3 2m away
with some fittings the extra 1.5m between the nearest and the furthest can be visibly dimmer!
so do all leads at 2m keep volt drop and dimming effect the same!
HTH
SL :x
GuinnessGuinnessGuinnessGuinness
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