Need help to build an AC Current Monitor

[Joberr]

Hello, all,

I need to build a circuit to monitor whether a device is working or not.  I need to verify if the device is working through the current that is being consumed, and can not be invasive.  Is like an ac current monitor.

The device consumes about 10A, but I do not need to measure the current, only if it is present or not.

 I'm thinking to use a current transformer as a sensor, I need help to build that current transformer too.

Thank you for your help

[bbarney]

check out these sensors from Allegro

http://www.allegromicro.com/en/Products/Part_Numbers/0752/

[Joberr]

Thank you for the tip bbarney, but I need something non invasive, I cannot open a wire to insert the sensor.

[sphinx]

well was thinking of an idea like a handheld as amp clamp meter it has a openable clamp u can open and measure amps comsumption thruu a wire, u can add electroniccs to that and tell if something comsumes current or not

best regards

[titi]

Hello,

May be, this can help you:
AC Current Monitor Senses high current-flow into power cables No wire-cutting

Web Site: http://www.redcircuits.com/Page62.htm
pdf file : http://www.khatereh.net/electronic/files/62.pdf

Best Regards.

[bbarney]

Have a look here
http://scienceshareware.com/how-to-measure-AC-DC-current-with-a-hall-effect-clamp-.htm

http://www.dentinstruments.com/CurrentTransformers.htm

[lillbear]

Well... i rather use this than CT

http://en.wikipedia.org/wiki/Rogowski_coil

yours

[Joberr]

Thank you all for the sugestions.

Yes bbarney thats what I need , something like that link  http://scienceshareware.com/how-to-measure-AC-DC-current-with-a-hall-effect-clamp-.htm

Titi, that´s a good idea, I will try. Thank you.

[bbarney]

That's what I really wanted to so you in the first place just couldn't find it,I'am pretty sure I've run across some hall-effects like my first post but you just run a wire over top.ONE OTHER THING IS SILCON CHIP-ELEKTOR-EPE have all done homemade current clamp articles at one time but for $10 that one looks pretty cheap to buy

[Joberr]

BBarney,

Do you think that is possible to use the ACS752 hall effect with out using  the leads 4 and 5? just putting the wire near the ACS752?

[bbarney]

It would probably pick up some current but I don't think it would be very accurate.I doe have one some where ? I could try a few experiments if I can find it 
Did you search allegro's site for non-invasive ones cause I'am pretty sure I've seen them somewhere, all you do is run the wire overtop the sensor.it might not have been allegro's site i seen them but look

[bbarney]

heres another link of sensors
http://www.lem.com/hq/en/content/view/270/207/

[Joberr]

Ok Bbarney, I sent an email to Allegro asking for informations, I´ll wait for the answer.

There are very good things in the other link, but I live in Brazil, and it is not so ea$$y to import parts, that is because I would like to build my TC.

I do not need the to be accurate, I only need to make sure my equipment is working, if not, an alarm will sound.

[bbarney]

OK ,so even if the ACS752 hall effect just let you know there was current that would be good enough for you,even if it was 75% off the real reading ? even a homemade clamp like I mentioned in one of the mags could work for that.
http://www.siliconchip.com.au/cms/A_30669/article.html