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Is the Behaviour of this Monitor Familiar ?


Active Member
Hi Guys

I'm hoping for some guidance .. I know nothing about much at all .. .. .. .

We have just taken possession of another business premises in which there are a number of POS systems, all of which have Wincor Nixdorf BA72R-3 TFT monitors .. .. .

The actual POS systems work but are useless because none of the monitors are functional.
I removed one today and into the workshop, fired it up with 12vdc @ 3amps the label says it needs.

It leapt into life immediately, showing the Nixdorf emblem and then a box stating 'No Signal' but then after a few seconds screen dies and that's it, nothing more.

As far as I can ascertain, it's drawing about 500mA when the emblem appears which drops to 200mA when the No Signal appears; When all goes off, it drops to about 20mA, not zero which is what I expected.

I'm not planning on messing with this too much because I know so little about them, but I did just wonder if this monitors' behaviour is familiar to those of you 'in the know' ?

I've attached a picture for the curious .. .. .





Active Member
It looks like the monitor is going into standby because of no video.
My computer monitor does the same thing, although it's powered by AC.

I suspect that the white box at the top of the picture is the inverter for the backlight.


Well-Known Member
Most Helpful Member
monitors will often go into standby mode when you turn them on with no signal. my immediate guess is that the power bricks for the monitors are bad. 20mA in standby mode is normal. if you repeat your test with a computer connected and operating, and the screen stays on, replace the power bricks for the monitors. if it still blacks out soon after being turned on with a video source connected, you are losing your backlight supply, and if you shine a strong flashlight at the screen and see outlines of things on the screen, it's only the backlight that's shutting down. the backlight supply is the board at the top of the picture, and it looks like you have fluorescent tube backlighting (the wires going to the backlight have high voltage insulation). occasionally the backlight wires can get hung up on sharp corners in the aluminum near where they come out of the panel, and arcing to a metal corner can cause the backlight supply to shut down.


Active Member

Thanks for the advice .. .. ..

I did wonder if the lack of a connected signal was the problem and connected a working PC but alas .. .. .. . ..

However, the flashlight trick seems to confirm a backlight problem .. …

At this point, I'm not going to pursue any further because once we have the business back on track we will install the same POS system we have in the other premises.

Thanks again



Well-Known Member
Most Helpful Member
If you google "POS", every one with a POS calls it a POS which does not help find out what it is. POS=POS
"define POS system" did get me to Wikipedia which is for dummies like me.


Active Member
Hi Ron

POS = Point of Sale .. .. .. .. .. . think of the checkout at Safeway or Esh's Discount Groceries .. .. .. .. .

These days, POS equipment has gotten very sophisticated indeed, with barcode scanners, scales, touchscreens, Atm's etc all in one unit. Much of that we don't need or use, but for us the ability to print multiples of a waxed transaction identification label at the press of a button is very important and labour saving.


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