Weird problem today lol...

[Darkwood]

Went to solve an issue on a lathe which is just part of my daily routine but while their i was ask to look at an issue in the calibration room.

Scenario:-

Ring main has numerous measuring and balancing equipment plugged in - all small power item.
Computer stack that is linked to dual monitors and then data linked to a high resolution camera inspection microscope... within this microscope is a ring of led lights around the camera lens so far nothing out of the ordinary well! until while the led and camera are on and the computer software is relating the picture from the camera... all works fine until one other item of equipment is switch on in the lab 'a small magnifying glass with a circular florescent lamp' the minute the lamp is switch on the led's and camera on the microscope switch off and the computer gives a warning tone the same as when a USB is unplugged.

This is not coincidence!.. I repeated the scenario a few times and the computer program requires rebooting to gets things back to normal.

The are 5m apart on same ring main.
The flourescent lamp is small prob 18w ish but switch start.
Using a filter on the sockets does not rectify the issue.


My conclusion is RF signal interference matching the switching commands on an exposed PCB board at the camera/led position that is housed in a clear plastic cover...

Im going to return with a PCB starter for the magnifying lamp and going to glue a RF shield to the plastic cover housing the PCB control card for the camera and LED lights...


Im on top of it as most will know I don't often get stumped but just an interesting fault and wandered if anyone else had had similar freaky issues.

Note ring main test out fully and no issues with plugs etc...all common tests and observations were done and satisfactory.

 

[NickD]

What happens if the fluoro is already on and then the camera/LED set up is fired up after?

Can you see what happens if you power the fluoro off another final circuit via a long extension lead say?

What happens if you power the fluoro off a 12V lead acid and a car inverter?

 

[Pete999]

Went to solve an issue on a lathe which is just part of my daily routine but while their i was ask to look at an issue in the calibration room.

Scenario:-

Ring main has numerous measuring and balancing equipment plugged in - all small power item.
Computer stack that is linked to dual monitors and then data linked to a high resolution camera inspection microscope... within this microscope is a ring of led lights around the camera lens so far nothing out of the ordinary well! until while the led and camera are on and the computer software is relating the picture from the camera... all works fine until one other item of equipment is switch on in the lab 'a small magnifying glass with a circular florescent lamp' the minute the lamp is switch on the led's and camera on the microscope switch off and the computer gives a warning tone the same as when a USB is unplugged.

This is not coincidence!.. I repeated the scenario a few times and the computer program requires rebooting to gets things back to normal.

The are 5m apart on same ring main.
The flourescent lamp is small prob 18w ish but switch start.
Using a filter on the sockets does not rectify the issue.


My conclusion is RF signal interference matching the switching commands on an exposed PCB board at the camera/led position that is housed in a clear plastic cover...

Im going to return with a PCB starter for the magnifying lamp and going to glue a RF shield to the plastic cover housing the PCB control card for the camera and LED lights...


Im on top of it as most will know I don't often get stumped but just an interesting fault and wandered if anyone else had had similar freaky issues.

Note ring main test out fully and no issues with plugs etc...all common tests and observations were done and satisfactory.

When you say it switched off, what exactly switches off, cb rcbo or rcd

 

[Darkwood]

Its the switch start that causes it ...you can run the inspection camera after turning the mag' lamp on no issue but turn it off then back on again while switch striking the lamp it always takes the camera and LED's out.... RF interference ...Ill confirm this and did run the camera and computer from a different source and still same result so not circuit related.

As I said im on top of it but just a weird one ...been in the business 25+ yrs and still get the curve balls.

 

[Brightspark2]

When you say it switched off, what exactly switches off, cb rcbo or rcd

Think he means just the equipment itself switches off...

 

[Darkwood]

When you say it switched off, what exactly switches off, cb rcbo or rcd

The LED lamp and camera on the inspection machine - the computer program running it still working and the power still present but it has seen a switch off signal like the computer has told it to turn off hence the computer also reacts as though it has been disconnected too.

No power issues or loss occurs its a PCB control board that receives a spurious command to turn the LED and camera off whenever this unrelated magnifying lamp is turned on.

 

[NickD]

did run the camera and computer from a different source and still same result so not circuit related.

How different? 12V lead acid and car inverter, go on, you know you want to....

been in the business 25+ yrs and still get the curve balls.

Maybe change your underpant brand.

Place I used to work, the guards' walkie talkies used to trip the lab bench RCDs, but obviously that's orders of magnitude more radiated power.

 

[NickD]

Ooh, hang on, how are the camera and LEDs supplied, via the USB or via external power source? If the latter...ground loop?

 

[Darkwood]

Alternative source was a power socket on different phase not a lot i could do in the time scope and I've bigger fish to fry like getting their machines working so will pop back at a more convenient time.

 

[R G]

Its a possibility , but with the switch start this cases a momentary loss of neutral , this maybe whats affecting the supply to the computer , is there any chance the capacitor in the fitting is faulty , some of these Florries affect RCDs with a similar effect with loss of neutral , so its a possibility . just a thought like,,

IMHO ,I don't think I would consider putting floury fittings on the same circuit as computer equipment if I could help it myself,,

 

[Darkwood]

As stated earlier on original post all circuit testing done all plugs and power leads fine - any other item switched on anywhere in room has no effect its just solely the switch start of the inspection lamp - the RF exposed PCB next to the camera was the first thing I saw and as its not housed in a metal enclosure its exposed to any airborn radiation and only requires a frequency match to tell send a off commad.

 

[stevethesparks]

I would suggest that any relevant leads to be wrapped around within a ferrite ring, the more windings the better.
Although its a totally different scenario, I once put an alarm system in for a radio ham, and every time he keyed his mic, the alarm system locked up. It was his idea and expertise in his field that we introduced a ferrite ring at each end on the keypad wiring, and this done the trick. The problem never replicated itself again.
So if you have some rings handy, it could be worth a try.

 

[Darkwood]

The cables already have ferrite rings on them as above I'm not asking for solutions although appreciate the input...I'm well educated as most may tell you on here (not trying to be big headed either) .. I was merely asking of similar experiences out there..


My day today ....

Job 1- Loss of controls on a lathe - blowing fuse wire when TX secondary fuse replaced - traced to collapsed full wave bridge rectifier.
Job 2- as above thread post.
Job 3- 2m saw blade carriage motor has speed issues at a certain point and was sometimes stopping - faulted it as a 2mm variation in track alignment and the drive running at 6hz lacked the torque to carry it further, drive did multiple motors so didn't trip as separate overloads and as it also forced vented didn't exceed OL rating - Advised customer of the dis-alignment issue and gave a temp' solution to give a voltage boost at low speed, this solved it and will not need further works unless the alignment issue increases.
Job 4- Generator tripped out ... sourced 37Kw motor giving pulsating current ramps due to nature of duty ...meaning the generator was revving every 2 seconds an extra 80 amps well within its current limits but not in its supply design so tripping...

3 of the above had had other Engineers out on site before me as a cheaper option but they learn the hard way ...(now im been big headed lol)

So a RF interference issue is a tad background to my normal run of the mill fault finding when I solve screening issues etc on everything from POT's to Encoders, In precision engineering you would be surprised what can corrupt your data cables and control cables.

 

[Engineer54]

Its the switch start that causes it ...you can run the inspection camera after turning the mag' lamp on no issue but turn it off then back on again while switch striking the lamp it always takes the camera and LED's out.... RF interference ...Ill confirm this and did run the camera and computer from a different source and still same result so not circuit related.

As I said im on top of it but just a weird one ...been in the business 25+ yrs and still get the curve balls.

Eliminating suspected RF interference would be the first course of action i'd take too...

 

[NickD]

Eliminating suspected RF interference would be the first course of action i'd take too...

Question is, be it airborne or be it copperborne...we shall see!

 

[Hawkmoon]

Maybe worth trying an electronic starter? Perhaps the em effect would be reduced

 

[Engineer54]

Question is, be it airborne or be it copperborne...we shall see!

It may well be, but eliminating/reducing any RF is a good place to start!!...

 

[Darkwood]

Maybe worth trying an electronic starter? Perhaps the em effect would be reduced

As in my opening post ...Im going to fit a PCB starter as part of the plan attack to change the RF frequency hopefully.

 

[Hawkmoon]

Didn't read properly - again lol

 

[Eddiesparks]

This one sounds a lot like witchcraft.

Call the elders to the ducking stool!!

 

[NickD]

Only if darkwood weighs the same as a duck. Which means.....he's made of (dark) wood.