Re: [CAD_CAM_EDM_DRO]Major encoder trouble, need advice.

As far as I know US digital uses Agilent read heads which use to be HP.
Dan Mauch
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----- Original Message -----
From: Jon Elson
To: CAD_CAM_EDM_DRO@yahoogroups.com
Sent: Wednesday, November 26, 2008 7:22 PM
Subject: Re: [CAD_CAM_EDM_DRO]Major encoder trouble, need advice.


Henrik Olsson wrote:
> Hi guys,
> Wow, almost two MONTHS have passed... It took a while for the Renco encoders
> to arrive but now they are here and FINALLY this project seems to be back on
> track.
>
> I have mounted one R35i on one of the motors and although I haven't run it
> that much yet I've had zero problems with it. I probably have around 90
> minutes of continous testing in it and there seems to be no sign of the
> problems the USDigital encoders showed.
>
> First I tried with roughly 300mm cable and then went to ~15m (around 50
> feet) and it seems to work just fine. The powersupply and cables are EXACLTY
> the same as with the USDigital encoder and the grounding/shielding scheme is
> also EXACTLY the same.
>
>
Well, without seeing the signals myself, I can't really add much, except
that I was pretty sure your problems WERE due to some weakness in the US
Digital encoders. This is about the 3rd time I have heard of this
problem. They seem to be very sensitive to electrical noise. You'd
think an encoder manufacturer would have some sort of electrical torture
test they subject their new designs to, such as the encoder needs to
operate perfectly with X amount of P-P noise superimposed over 5 V DC
+/- X % variation. Only after proving correct operation over a really
worst-case test should they sell the product. I'm afraid US Digital
just isn't doing that.
> I will continue to test this during the coming days and then I will contact
> USDigital again and see what they have to say about it. Right now they
> aren't one of my favourite companies....
>
> I'd like to thank everybody who contributed to the thread. A special thank
> you goes to Jon Elson for recommending Renco Encoders. Hope I didn't speak
> to soon and jinxed it now..... I'll post more when I've done some more
> tests.
Glad I was able to help.

Jon




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