Hall effect current module oddity

Using Arduino General Electronics
#1

I'm using a hall effect current module to measure the current and AH consumption of a pair of LED lights and fan on our trailer tent. It's a bit of overkill, but I'm doing it to avoid running the car battery too low.

It worked OK running the LED lighting directly, but when I installed a couple of wireless controllers to remotely control on/off and dimming the lights I encountered problems.

The problem is that with the hall effect device in series, the controllers don't work and remain on at full brightness. Also the fan doesn't work. If I remove the hall effect device, all works as it should.

I'm puzzled! The hall effect device shouldn't affect the current flowing through it - but it appears to be. I'm running the device well within its ratings .

This is the dimmer for the lights: http://www.ebay.co.uk/itm/12V-24V-8A-LED-Wireless-Dimmer-RF-Remote-Controller-for-Led-Strip-Lamp-Light-New-/261288063384?pt=UK_Home_Garden_Lighting_Parts&hash=item3cd5fb7198

This is the hall effect module: http://www.ebay.co.uk/itm/ACS712-current-sensor-module-5A-range-arduino-PIC-LONDON-CITY-UK-FREE-POST-/121182465805?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item1c3709af0d

Any ideas as to what the problem might be, please?

Jim

#2

Schematic?

#3

Odd - what frequency wireless control? Are you inserting the hall sensor in the positive supply or the ground return ? Those particular sensors introduce a little stray capacitance to the sensing circuit, but shouldn't have any other effect, since the sensor consists of a copper ribbon in the chip passing over an insulated hall chip - its basically no different to a copper wire.

However if there is some radio-frequency interaction going on it will be hard to track down (I would expect the current monitoring to go haywire, not the device to stop working though).

Perhaps there is a dodgy connection somewhere?

#4

MarkT: shouldn't have any other effect, since the sensor consists of a copper ribbon in the chip passing over an insulated hall chip - its basically no different to a copper wire.

Yes, that's what I thought.

would expect the current monitoring to go haywire, not the device to stop working though{/quote]

It was not the current monitoring that stopped working, but the two dimmers and fan it was monitoring. The dimmers stayed on and wouldn't turn off or dim, and the fan (a 12V computer one) didn't work.

I'll do a bit more digging into the problem.

Thanks for the reply.

Jim

Perhaps there is a dodgy connection somewhere?

#5