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I am using relay circuit for inverter application. It's 12V relay having coil and two contacts for connecting line and neutral respectively.

But, I am not getting closed connection when I am giving 12V to the collector and Logic 1 to the base from dsPIC. Logic 1 from dsPIC is at 2 volts.

Relay is ALA2PF12. I have attached schematic.

Schematic

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  • \$\begingroup\$ Lose R65. While you're at it, fix the schematic to get rid of the "box" above and right of the collector. You should be able to see for yourself that all those lines are connected together, so having them cross over each other makes no sense. \$\endgroup\$ – Olin Lathrop Oct 15 '14 at 12:49
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Put a diode across the coil, cathode to 12V_PV, and as everyone else has told you, get rid of R65.

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Why is R65 in there? Try shorting it out. The relay coil needs 530 mW, which would be 44 mA @ 12 V, and implies that the coil resistance is about 270Ω.

A 100Ω resistor limits the current to 32 mA, and the voltage to 8.75 V. The latter is less than the pick-up voltage of 9 V specified in the datasheet.

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