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[SOLVED] Relay Circuit to Power Light Bulbs

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May 13, 2015
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i want to know how to control the voltage of light bulb 220V using relay ?

if i want to use 1 relay with 12V DC, that means if i give 12V DC, the light bulb is on and when 0V, the light bulb is off.

the questions :
1. if i want to create so much output to light bulb like 50V,60V,70V......220V, how the circuit should be ? can you teach me how ? thanks
2. if i give 8V DC as an TRIGGER on relay, is the light bulb will ON ?

Thanks if you can teach me more.

When you meet Vmin on coil, it is guaranteed to switch but will switch slower perhaps with more contact bounce.

Since light bulb has cold R 10x lower than hot the surge current is up to 10x higher when turned on which can derate power capability or lifetime of relay contacts.

To choose different voltages on contacts involves your voltage source design, which may be AC, DC or PWM DC or SMPS DC-DC etc.

See OMRON site for everything you wanted to know about Relay characteristics and reliability ratings or reduced power ratings or contact switch life or MTBF vs load from like surge currents of HP rated motors or tungsten bulbs or DC limits with inductive loads ( arc) or best case resistive loads.
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