Forum

Full Version: Problem with on Shahe Scale
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Ideas needed please. 
I have a mini mill with 3 Shahe scales. Copied Andrew Whales UTUBE instruction on fitting the scales. All work nicely. I built the DIY kit and pleased to say that it worked straight off. Problem is with the X axis scale. The display pulses random numbers and does not work. The other scales are stable and work OK. It does not seem to be the DRO board as I have isolated the problem to the scale. The problem scale works with remote scale reader that came with it.
The scales are using the DRO board power which I have measured at 3.03 volts. This is a bit below 3.3v that it should be. Could this be related to the problem?
Hi Ken, I think I recall some users having issues if the read head had been removed from the scale and then accidentally re-installed the wrong way around. Is that a possibility?


Update: here's the link to the earlier post https://forum.yuriystoys.com/showthread.php?tid=767
Ken,
3.03V should not be a problem for the scale. That said, 3.03V is strange. You should be getting 3.3V on the board. That is what the regulator is set for, and there should be no reason to have that drop. What is the power supply voltage?
I haven't heard of this sort of a problem with Shahe scales. To be sure: you have plugged this scale into other inputs and are getting the same behavior, correct? Are there any other differences? Does the scale work with any of the other displays?
Regards
Yuriy
Hi Yuriy,

Thank you for your quick reply.
I am using a variable bench testing power supply and I have played with the voltage around 5v. I noted that the two resisters supplied with the kit were 330 ohm and not 220 ohm as specified in the build instructions. I did use the kit resistors. 
The problem is definitely with the one scale (X on my mill)  as it acts up no matter which input that it is plugs into. It seems to be a pulse of about a couple of seconds of random readings. This repeats. This scale works OK with the rectangular Shahe displays that came with it. 
Over the weekend I will take the offending scale off the mill and see if it is OK on the bench. 

Ken

Hi Norman,

I did not recognise the fact that there is a "right" way to put the scale together! I did shorten the scale and took the reader off when I chopped off a few inches. Thank you and I will try the other way over the weekend when I get back into my shed. 
I really appreciate all the help.

Ken