Problem with Arduino hang (Xenon lamp)

Hi!

Sitting here and play around with Arduino Uno R3. But have encountered a strange problem. I have created a simple sketch of a few lines to send data to a PC over USB. Now connected a LM35 temeratursensor to analog pin 0. I also tried with a LDR, and same problem. The data is sent with 100 ms delay, but is the same if i use more delay.

Here’s the problem:
It works fine until I turn on a lamp on my desk. I think it’s a Xenon bulb in it. It is a 12V transformer in the base of the lamp, standing next to USB cable. When I turn on the lamp, transfer to my computer and TX LED on the Arduino will stop blinking when data is being sent. If I dont turn on the lamp it works just fine. Its the same problem when I turn the lamp off if it allready was on. To get it to work again I have to either reboot the computer or reinstall the driver for the Arduino. Nothing else works.

Anybody have any idea what this may be?

HID (Xenon arc) lamps, if not really well made, can radiate a lot of RFI. Maybe that's what's causing it.

Could try using a USB cable with ferrite chokes on either end.

Are you sure the lamp has transformer, or is it a switch mode power supply.

By the sound of it you have switching transients or swmp radiated interference.

Just move the cables apart, try not to let them run parallel to each other.

Tom

It's connected to the same plug socket right?

Simply pull it out and connect the lamp to another socket / seperate circuit, i bet the back emf is hitting everything on your power block...

Sounds weird. Xenon bulbs are the kind you see in a camera flash. The bulbs used in modern cars are HID (High Intensity Discharge) and they are mistakenly called xenon, because: a: it sounds good, b: they contain a small amount of xenon gas to help ignite it when hot

A desk lamp with a HID light source doesn't sound right to me, in any way.

Can you take a picture of the lamp and the bulb and post it here ? - you've got my interest ;-)

HID bulbs are also technically xenon bulbs and there are several types of them. They are what are termed xenon short-arc lamps and the arc is run at high frequency. Flash bulbs are more like xenon long-arc lamps and are generally fired with single shots or at low frequency. The xenon is in there for exactly the same reason it's in a xenon flash bulb as they essentially work using the same principle of electrical gas discharge. Think of HID as little flash bulbs flashing several thousand times a second. They can and do produce EMI/RFI. They are (were) fairly commonly used in desk lamps and accent lighting and used to replace low efficiency halogen units for those that could afford them. Although longer lasting, whiter light and far more efficient than halogen, they are/were far more expensive. Recent developments in high power LEDs make them the choice these days to replace both expensive HID and inefficient halogen lamps in such applications. The most common and sensible uses for xenon short-arc HID lighting now is for theater projection lamps and automotive driving lights. The automotive type typically employ metal-halide for the main light source for greater efficiency and more tunable light temperature. In these units, the HF xenon arc is usually only employed for the first minute or so until the metal-halide salts are up to operating temperature.

As suggested, you should try to move the lamp or Arduino to a different outlet and further away from the lamp.

BillO:
HID bulbs are also technically xenon bulbs and there are several types of them. They are what are termed xenon short-arc lamps and the arc is run at high frequency. Flash bulbs are more like xenon long-arc lamps and are generally fired with single shots or at low frequency. The xenon is in there for exactly the same reason it’s in a xenon flash bulb as they essentially work using the same principle of electrical gas discharge. Think of HID as little flash bulbs flashing several thousand times a second. They can and do produce EMI/RFI. They are (were) fairly commonly used in desk lamps and accent lighting and used to replace low efficiency halogen units for those that could afford them. Although longer lasting, whiter light and far more efficient than halogen, they are/were far more expensive. Recent developments in high power LEDs make them the choice these days to replace both expensive HID and inefficient halogen lamps in such applications. The most common and sensible uses for xenon short-arc HID lighting now is for theater projection lamps and automotive driving lights. The automotive type typically employ metal-halide for the main light source for greater efficiency and more tunable light temperature. In these units, the HF xenon arc is usually only employed for the first minute or so until the metal-halide salts are up to operating temperature.

As suggested, you should try to move the lamp or Arduino to a different outlet and further away from the lamp.

Might be, but the HID UHP lamps used on projectors, headlights etc. are all run on low voltage DC, not high frequency.

The Xenon short-arc lamps, like used in stage lighting and cinema movie projectors run at a low DC voltage as well. 20-30V DC at hundreds of amps. They are ignited with 30Kv, and then it’s pretty much a dead short, so the voltage across the lamp is very low.

// Per.