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Amps drawn by devices from Power supply

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djranis

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I have been told by my power supply maker that my power supply has a limit to 3 Amps. He explained that collection of devices that draw more than 3 amps will damage my power supply. Can anyone suggest me how to calculate power drawn by a device ? I am confused over the fact if it has anything to do with Resistance or Gain of the device.
 

kak111

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Best way is put a current meter in series with one device and check current value.
Do same to all devices.

Then all connected devices take sum of their currents from power supply.

KAK
 

Syncopator

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It sounds as if your supply has no protection at all at the output. If this is so, you might like to consider wiring a 3A fuse in series with the output. It could be in a panel-mounted holder, or in an in-line fuseholder.
 

djranis

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Thank you all for replying. SO basically the whole circuit with multiple devices can be imagined as multiple devices connected parallel to a source and upon dividing source voltage by overall parallel resistance the amps can calculated. Therefore if amps > 3 amps only then is it hazardous to my power supply? Syncopator thanks for your concern about the fuse and yes my power supply does have a fuse.
 

Syncopator

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Thank you all for replying. SO basically the whole circuit with multiple devices can be imagined as multiple devices connected parallel to a source and upon dividing source voltage by overall parallel resistance the amps can calculated. Therefore if amps > 3 amps only then is it hazardous to my power supply?
Yes, that's correct.

Syncopator thanks for your concern about the fuse and yes my power supply does have a fuse.
Is the fuse in the primary, i.e. the mains supply? If so, I would like to see an additional one in series with the output.
 

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