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I have been reading your articles on power supply in readiness for starting to build a home automation system using Loxone equipment.
I feel confident in the project but the power supply situation leaves me a bit perplexed.
I am intending to use 8 TDK Lambda (DRF240-24-1) power packs to drive the 24V DC LED lighting in my new house.
Each power pack has a rated input of 100 – 240 VAC 2.7A. The output is 24 – 28 V DC 10 – 8.6A.
So that is a power requirement of 648W for an output of 240W.
My first question is where is the missing 408W? I realise that the pack itself will require some energy to work, but I would have thought that would be around 20% of the input.
Secondly; if the input is rated at 2.7A x 8 power packs then I will need an RCB in the consumer unit rated at over 21.6A, - or more likely several lower rated RCBs to split the load into zones.
Am I missing something here?
From the 8 Power packs there is a total power available at 24V DC x 80 A = almost 2,000W whereas to provide this I have to supply 21.6A x 240VAC = over 5,000W. Am I going wrong somewhere?
Any observations would be appreciated especially if I am completely failing to understand this issue.
Thanks in anticipation.