Seeking low-current (<10A) clamp-on DC current probe

[davidd31415]

I'm looking for a low-current clamp-on DC current meter to use as a
current indicator; anything else that might work as a
current/no-current check device would be great as well. The quicker a
single check can be performed the better as I'll be checking 30 wires
on a regular basis.

I've thought about using LEDs in series but two problems arise. The
wires will be moved regularly so I would need wires and strain relief
to ensure the LED legs do not break off and more importantly, the
voltage across the loads is changed dynamically and is measured inside
the power supply. Using one load for sensing is not an option in case
of a single failure and approximating the voltage drop will only be
okay if all LEDs are guaranteed to be within +/- .1V of each other and
have a constant voltage drop throughout use at slightly varying room
temperatures and humidities.

 

[mike]

I'm looking for a low-current clamp-on DC current meter to use as a
current indicator; anything else that might work as a
current/no-current check device would be great as well. The quicker a
single check can be performed the better as I'll be checking 30 wires
on a regular basis.

I've thought about using LEDs in series but two problems arise. The
wires will be moved regularly so I would need wires and strain relief
to ensure the LED legs do not break off and more importantly, the
voltage across the loads is changed dynamically and is measured inside
the power supply. Using one load for sensing is not an option in case
of a single failure and approximating the voltage drop will only be
okay if all LEDs are guaranteed to be within +/- .1V of each other and
have a constant voltage drop throughout use at slightly varying room
temperatures and humidities.

Not sure exactly what you're doing, but a compass laid on the wire will
tell if there's any current in it. You can get one with a "calibrated"
dial on it at an auto parts store. Or you can pay as much as you desire
for a non-contact DC current meter.
I've got a FW Bell CG-100A clamp-on DC current probe I'll sell for $50.
Needs external voltmeter for readout.
mike

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[Jasen Betts]

I'm looking for a low-current clamp-on DC current meter to use as a
current indicator; anything else that might work as a
current/no-current check device would be great as well. The quicker a
single check can be performed the better as I'll be checking 30 wires
on a regular basis.

I've thought about using LEDs in series but two problems arise. The
wires will be moved regularly so I would need wires and strain relief
to ensure the LED legs do not break off and more importantly, the
voltage across the loads is changed dynamically and is measured inside
the power supply. Using one load for sensing is not an option in case
of a single failure and approximating the voltage drop will only be
okay if all LEDs are guaranteed to be within +/- .1V of each other and
have a constant voltage drop throughout use at slightly varying room
temperatures and humidities.

A regular clamp probe issn't sensitive enough, (I can buy a kitset one
with 100ma sensitivity) jayccar.com.au catalogue number 5368, it'd need
some (but probably not much) modification to drive a LED indicator
directly.

you can put a loop with ten turns in each wire (which will multiply the
current sensed by the clamp probe by 10 if it's clamped on the loop.

Bye.
Jasen