Im wiring lights in series, and have come to a part where I can only have 2 lamps. The bulbs I am using are 60v 10w, what is the best resistor to use to make the circuit 240v so the two lamps will work on the circuit. Thanks
I would recommed the use of a transformer.
A transformer from 240 to 120 Volts (if the lams are in series) or 240 to 60 Volts (if the lamps are paralel).
A resistor would "burn" the also 20 Watts (the same as the 2 10 Watt lamps), wich is not economical.
My question was,,, Has anyone got a recommendation what they have used with regards a resistor to complete a series circuit when I need to complete a circuit with just two lamps.. I can use 4 lamps and place two of them them out of sight, alternatively I can get two 110v lamps and wire a twin series or two 230v lamps and wire the last two in paralell, or I can place a resistor or resistors in the series circuit.
A transformer isn't an option for two lamps, and LEDs are fantastic, but expensive, and I have the 60v 10w system wired and working except the last 4 on the series circuit.
All things being perfect, what you will need is a 720 ohm resistor which will dissipate at least 20 watts. I'd go wtih a higher wattage rating because running at the peak rating of any component is asking for it to fail fairly quickly. Oh, and expect it to get spit-sizzlin hot. I'd use a 25 watt rating at the least. Here is a link to what a 25 watt resistor looks like. http://www.electronicplus.com/images/products/L25J700.jpg DO NOT use your standard 1/2 or 1/4 watt resistor from radio shack. Those just won't hack it. You can use a value that's close, like 700 ohms, which will make the lights burn a tad brighter, which shouldn't be a problem. Or go with a little higher like a 750 ohms, which will make the lights just a touch dimmer. Neither deviations should be noticeable.