Mitutoyo DRO problems

[stevec]

I had a bit of a scare yesterday when I turned on the DRO on my mill.
The display started it`s normal blinking of 8s that it does before it stabilizes and then I normally zero each scale and I`m good to go.
Yesterday it wouldn`t zero and the decimal point just sorta flickered.
After pushing the on/off button a couple of times it started to work but didn't last.
I removed the cover after checking the power cord and fuse, I was expecting it might be a bit of corrosion on contacts eventually I jumpered the on off switch and the DRO stabilized and started to work properly. Before taking out the double pole on/off switch I decided to jumper a load across the poles on the DRO side of the switch. I chose a 13W CFL bulb for lack of a more suitable light load.
After that every time I turned the DRO on it lit the light and worked as it had in the past.



I'm suspecting the switch contacts are a bit corroded or coated and because the DRO draws so little current the contact(s) were unstable.
With the added load of the light the contact seems to be more definite.
Does anyone have a different diagnosis?

I suppose I should change the switch but I doubt if I'll be able to get an exact replacement so it'll require a bit of modification. But then,
I can always use more light in the shop so the light bulb may just stay there.

   

[f350ca]

Sounds like you narrowed down the problem, at least it has an actual switch, my Fagor uses push buttons on the pad. (turns itself on every time there's a power outage). Can you get into the switch with spray contact cleaner, or a bit redneck but maybe jumper the internal one and instal an inline switch.

[EdK]

Steve,

If you can get a good closeup picture of the switch, I might be able to find one for you.

Ed

[stevec]

Thanks for the offer Ed.
Here are the first pics.
           

I didn't caption the pics because I went a bit further.

and took the switch out.
           

Don't go to any great lengths to source a new switch ED I jumpered it out of necessity and now my DRO turns on when I turn on the control circuits and lights for the mill. It just means I'm less apt to leave the DRO on when I leave the shop.

I got carried away jumpering out the switch at the receptacle where the switch used to plug in, put the covers on and re-attached the DRO to it's bracket on the mill without taking pics.

I doubt if the switch is even available, if it is it'll prolly be ridiculously expensive.

[EdK]

Any brand name on that switch Steve? I'll bet there's a switch still available. Those industrial type switches have some degree of standards as to size.

Ed

[stevec]

Thanks again ED but please don't waste any time on it. I doubt if I'd even bother putting in a new one even if I got it for free.

[EdK]

Steve,

Just in case you change your mind, I've found some that would likely fit and they're about 2-3 dollars.

Ed