# Current sensing device

#### ian.blue

Joined Jul 12, 2011
31
I am looking for a way of sensing current flow in an 2 wire 250volt AC circuit.
the flow would be about 30amps and I would need a digital signal when current flows.
I do not want to tap into the live conductors but could this current be detected through the insulation?

#### thatoneguy

Joined Feb 19, 2009
6,359
Yes, A Hall effect type sensor can be used.

Is this a temporary or permanent installation?

Clamp ammeters that can measure DC use the hall effect for measurements, or you can order current sensors that are literally snapped around one wire and you get a tap out, usually 0.01-.1V/amp or less.

#### ian.blue

Joined Jul 12, 2011
31
This is intended as permanent arrangement merely to indicate digitally that the 30amp current is flowing.
You wouldn't have a ref no for a Hall effect sensor would you?

#### strantor

Joined Oct 3, 2010
5,187
when you say digitally, do you need the signal to go to a PLC or what? is just an LED ok? Check these out; I use them to indicate if my heater elements are in tact. its just a little deal you slip over the wire and the LED comes on if current is flowing. super simple

#### ian.blue

Joined Jul 12, 2011
31
Well thank you. These are so cute! What a great little product. I would never have found these in a month of Sundays. I love them.
Unfortunately I need an output which I can use to switch on a small load.
But I will order a couple of these for other uses anyway.

#### wmodavis

Joined Oct 23, 2010
739
You might also look at the
Allegro
® ACS714.

#### hgmjr

Joined Jan 28, 2005
9,029
You might also look at the
Allegro
® ACS714.
This device requires that the conductor carrying the current to be monitored be directly connected to the device. That requirement is counter to the poster's request for a solution that does not involve placing the monitoring device in-line with the current path. The poster is looking for a non-invasive current monitor technique.

hgmjr

#### wmodavis

Joined Oct 23, 2010
739
I guess I overlooked that part. It is an interesting chip however for several projects I'm thinking of.

#### thatoneguy

Joined Feb 19, 2009
6,359
Here is a panel mount 0-500A permanent mount meter (needs power supply), uses inductive pickup.