When looking at a used DRO, just the display with no scales attached, if it displays any digits other than 0's does that indicate there is something wrong?
It's impossible to say. My experience with the Acu-Rite readouts is that they'll display an error message if they were powered off then back on - this to keep you from thinking that they are really at the same 0,0 as before the power failure; I'd think that any other manufacturer would have a similar feature.
The ones we use on the mills at school, when you turn them on you have to hit "enter, clear" and then move the table a bit in the x and y axis before the dro starts working.
This website or its third-party tools process personal data (e.g. browsing data or IP addresses) and use cookies or other identifiers, which are necessary for its functioning and required to achieve the purposes illustrated in the cookie policy. To learn more, please refer to the cookie policy. In case of sale of your personal information, you may opt out by sending us an email via our Contact Us page. To find out more about the categories of personal information collected and the purposes for which such information will be used, please refer to our privacy policy. You accept the use of cookies or other identifiers by closing or dismissing this notice, by scrolling this page, by clicking a link or button or by continuing to browse otherwise.