Re: how to torture an engineer [jokes]


<mrdarrett@xxxxxxxxx> skrev i en meddelelse
news:1154722838.268810.292430@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Q: How do you torture an engineer?

.... Have him fix his own damn product!

I just stripped down a single-phase UPS bought cheap* at an auction to see
why the sucker would not start - turned out that the control voltage comes
from the batteries which sort of makes sense because if the batteries are
flat then they probably will go "poof" when charged at the usual high rate.
Hmm.

Now, to charge the damn batteries one has to *dissect* the bloody thing to
get each battery out and charge it indívidually.

The wires one has to take off are not labelled so one has to label.

Then i notice that they used about 80 chips (LM324 and "classic" CMOS) to
make up the control section ....

Then I finally notice that the heavy power section and the control unit are
joined so wisely that one must be on top of the other so that one cannot
really test the thing as a unit on the workbench.

Now I probably recycle the batteries and some of the components - that thing
sucks - yet obviously the product was successful because the manufacturer
still exists.

To stop the control section from bleeding the batteries dry there is a
mechanical switch. Thus it is probably a normal case that the switch is left
ON and the unit has to go back for vivisection. Bit like the Citroen 2CV
when changing points or spark plugs!

* Paid USD 15.


.

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