ThomJ Posted May 17, 2005 Share Posted May 17, 2005 This is a stupid question but I cannot find anyone who seems to know How many amps does a single 30w 6v Pin Spot draw. The Normal WAV formula dont work(=5amps), as the unit has a transformer. How do tranformers affect the WAV calculation. :) Link to comment Share on other sites More sharing options...
Mush Posted May 17, 2005 Share Posted May 17, 2005 This is a stupid question but I cannot find anyone who seems to know How many amps does a single 30w 6v Pin Spot draw. The Normal WAV formula dont work(=5amps), as the unit has a transformer. How do tranformers affect the WAV calculation. :)<{POST_SNAPBACK}> Watts is always Watts, is worth remembering, something that pulls 30w at 6V will be pulling 30W at 240V apart from Transformer efficiency. Lets guess the transformer is 90% efficient, so 10% gets lost as heat. so your 30W lamp is effectively drawing 33W from 240V. P =I/V 33/240= 0.1375 A call it 0.14A for handyness or at 110V 33/110 = 0.3A Link to comment Share on other sites More sharing options...
Pete Alcock Posted May 17, 2005 Share Posted May 17, 2005 Thom, For all intents and purposes you can treat a transformer as 100% efficient in a case like this. Power in (Watts) = Power out (Watts). So on the low Voltage side of the transformer you have a 30W bulb on 6V drawing, as you rightly say, 5A. On the mains side it's consuming 30W of power at 230V so the current draw is 30/230 = 0.13A. It'll be a bit higher than this actually because the transformer isn't 100% efficient (it gets warm). Pete. Sorry - Mush must've posted whilst I was still writing. Link to comment Share on other sites More sharing options...
Andrew C Posted May 17, 2005 Share Posted May 17, 2005 You may already know this, but I'll add it just in case... Unless you are sure of your dimmers ability to dim inductive loads - don't. You'll trash the transformers, and while they can be replaced it's a bgr of a job! Link to comment Share on other sites More sharing options...
Flyingwysiwyg Posted May 18, 2005 Share Posted May 18, 2005 You may already know this, but I'll add it just in case... Unless you are sure of your dimmers ability to dim inductive loads - don't. You'll trash the transformers, and while they can be replaced it's a bgr of a job!<{POST_SNAPBACK}> Or if you are unsure, you can add a resistive load (a load lamp) into the circuit (such as a PAR can back stage with some 119 on the front) F - Wyg Link to comment Share on other sites More sharing options...
Andrew C Posted May 18, 2005 Share Posted May 18, 2005 You may already know this, but I'll add it just in case... Unless you are sure of your dimmers ability to dim inductive loads - don't. You'll trash the transformers, and while they can be replaced it's a bgr of a job!<{POST_SNAPBACK}> Or if you are unsure, you can add a resistive load (a load lamp) into the circuit (such as a PAR can back stage with some 119 on the front) F - Wyg<{POST_SNAPBACK}>Tried that, still killed 'em off! May be the JTM dimmers I'm still using! Link to comment Share on other sites More sharing options...
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