double ended 360 degree pot sources.

It's probably worth asking Honeywell directly. There is a pretty good chance that they will tell you either "no" or "we will restart the production line for a million bucks", but there's a small chance they'll say "yeah, we don't make those anymore, but our other customers have changed over to the 123 series from Acme".

They also could be small quantities of surplus or new old stock units. Some vendors will price them that way, especially if they have any idea that the part was ever used in a highly regulated design (aerospace, military). Buying a $500 pot might make sense for low-volume repairs of a device that there is a contractual obligation to support; $500 wouldn't even begin to cover the engineering time and paperwork to certify a different part.

Hollow shaft pots exist; you could install your own shaft in the configuration needed. Finding hollow shaft 360 degree pots is a little harder but there are least datasheets for some of them:

Expensive *looking* one with 355 degrees:

One with continuous mechanical and 340 degree electrical:

More from the same company here:

One with 360 degree mechanical and either 330 or 360 degree electrical (note the handy 1200 piece minimum):

Inexpensive *looking* one with 270 degrees:

I don't know if any of these parts suck or not; I just Googled them up.

Standard disclaimers apply; I don't get money or other consideration from any companies mentioned.

Matt Roberds

Rather hard to make huge profits on a one-off $500 custom order, in fact it's almost guaranteed to lose money. They're pretty much telling you to get lost.

Have you tried using a search engine, such as Google?

Surplus 2K pots for only $50: (dual 1/8 OD x 1/4" shafts)

New Indian ones, probably not too expensive (6mm shafts)

Surplus 1K CT pots withy dual shafts (6 available, it says)

(resent with correct subject line)

Rather hard to make huge profits on a one-off $500 custom order, in fact it's almost guaranteed to lose money. They're pretty much telling you to get lost.

Have you tried using a search engine, such as Google?

Surplus 2K pots for only $50: (dual 1/8 OD x 1/4" shafts)

New Indian ones, probably not too expensive (6mm shafts)

Surplus 1K CT pots withy dual shafts (6 available, it says)

our problem is we need to source these to be able to get these later..

For a couple of service jobs, getting someone's old stash from E-Bay or where ever would be ok.

I would rather say away from ganged pots, the space where this must fit is tight. But that was a good fine however, you did better than I did..

Thanks. Jamie

yes, I found many of those when I was doing my search. We need one that is designed for industrial use, since it is going to take a little beating..

Many of them are plastic resistors and I've found those to lose their linearity over use, way before they actually get mechanically worn out.

I've look around some more today and called some people, it looks like we may need to rethink that section and employ a different technique.

So, we experimented with a linear inductive prox and a eccentric cam wheel that can be mounted on a shaft. The problem with this is, this section of the equipment must be very accurate and maintain to prevent erratic sensing.

After looking at absolute encoders, it was determined that machine vibration in this section may be short lived.

Thanks

jamie

There are lots of linear and angular displacement sensors that are suitable for use on machines, vibration al all, with very high accuracy. What are you trying to do? How good does it need to be?

Joe Gwinn

I guess I need to recalibrate my approach, here.

There seem to be two kinds of "component selection" posts lately. One is where someone seems to be aware of all the major alternatives, and is asking just to see what is popular, or to make sure they haven't left something out or not heard about a new part, or is looking for "gotchas" with a specific approach. It looks to me like these kinds of posts result in more useful information, more quickly, for the original poster.

The other kind is where someone wants help selecting a specific part number, but only puts about 25% of their requirements in the first post. When people respond with suggestions and ideas, the response is "that won't work because of additional requirement X". I can understand not wanting to spill *all* the beans for commercial reasons, but defining requirements via "20 Questions" is not so much fun if somebody is working for free.

Matt Roberds

This might be a job for a synchro or resolver, though not cheap. They work even as propeller pitch sensors on big radial engines.

ok, I really didn't understand the bulk of what you were trying to convey, but what ever..

An alternate design has been agreed on. We're going to use a analog inductive prox with a 5 mm range and a eccentric target. Total cost for the prox is under $100 if we buy 10 or more and this technology does not appear like it's going to be obsolete any time soon. Plus it gives us a better results over all including life expectancy.

Thanks to all that that helped out.

Jamie

It's an Avago metal code wheel for a 1/4 inch - 6.35mm - shaft with a three channel encoder that sits on one side of the code wheel. One of the channels detects an index slot, once per revolution.

Less messy than a cam and a linear displacement measuring system for finding out where the cam is.

channel encoder that sits on one side of the code wheel. One of the channels detects an index slot, once per revolution.

out where the cam is.

if I was to do that, we would be using an enclosed unit with hollow shaft, which we can get all day long from many places. Dynapar, redlion are some examples. The problem with the one you suggested is, that it's open frame, that would never work. Plus it is too low of PPR count.

We have gone with the 5 mm distance analog prox with an eccentric disc on the through shaft. Environmentally happier..

Jamie

they'll

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up.

Maybe you should look for rotary variable differential transformer (the rotary cousin to a LVDT). Or perhaps a resolver (see synchro as well).

?-)

I have a couple of Penny and Giles conductive plastic 360' servo pots with 1/4" double ended shaft. These are old, but maybe they still make them or similar.

Cheers