24 pulse rotary encoder with push switch

[Rob Sims]

Hi,

Anybody know where I can find high quality 24 pulse rotary encoders with push switch?? I have a Tekpower TP3005T power supply and the rotary encoders for voltage and current miss sometime when turning the knobs, especially when turning them a little fast. It's not super bad, but a bit irritating and frustrating. I want to change them as soon as possible.

[MosherIV]

Is this any good ?

http://cpc.farnell.com/alps/ec12e2424407/encoder-vertical-24-det-24ppr/dp/RE04233

[Rob Sims]

It looks a bit plasticy. I don't know. The ones I have are a plasticy and bit flimsy and also plasticy Hope someone who had to work with a one of decent good quality can reply.

[alanb]

On a couple of projects that I have built I have had problems with the encoders missing when turned. In both cases the problem has been due to firmware rather than the quality of the encoders and was improved by a firmware redesign. Because of that better encoders may not solve your problem.

[Rob Sims]

Ok, so I need to check the encoders on the unit first. If they are in good shape, then it's the firmware. If it is the firmware I can throw the unit away because there won't be any firmware updates for these cheap Chinese power supplies. I think the analog controls with potentiometers are still the best way to control current and voltage on a power supply.

[alanb]

Ok, so I need to check the encoders on the unit first. If they are in good shape, then it's the firmware. If it is the firmware I can throw the unit away because there won't be any firmware updates for these cheap Chinese power supplies. I think the analog controls with potentiometers are still the best way to control current and voltage on a power supply.

There are two areas of concern with the encoders. Firstly there is contact bounce this may be handled by the firmware but if not you may be able to improve matters with a capacitor across the contacts. The second is if the changes are being detected by repeatedly checking the contact state in a loop, this is subject to timing and the microcontroller having to do other tasks in the loop can cause it to miss changes when the encoder is turned rapidly. This can only be rectified with a firmware re-design.

If you cant resolve the encoder issue you have most of the parts to rebuild the power supply using analog controls.

[Rob Sims]

Thanks for the advice alanb.

[Tomorokoshi]

If possible, take apart the encoder and clean off the grease that made its way to the contacts. Then spray it off with 3M Novec cleaner if you can get it.

[Rob Sims]

Thank you, very helpful. I'll try this first.

[C]

Ok, so I need to check the encoders on the unit first. If they are in good shape, then it's the firmware. If it is the firmware I can throw the unit away because there won't be any firmware updates for these cheap Chinese power supplies. I think the analog controls with potentiometers are still the best way to control current and voltage on a power supply.

You could replace existing firmware with firmware you create.

You could make existing firmware by better encoder input.
 You could read the encoders with your own micro controller and then output a de-bounced & speed limited encoder output to existing encoder input.

Using an optical encoder does some of the de-bounced part above.

[Rob Sims]

Thanks C. The big question is how can I replace or upgrade the existing firmware. How do I program the micro controller. Where can I find information. I have a schematic of the power supply. If someone is willing to help I can email it.

[C]

Thanks C. The big question is how can I replace or upgrade the existing firmware. How do I program the micro controller. Where can I find information. I have a schematic of the power supply. If someone is willing to help I can email it.

Think that is to large of a first step for you. If you do much in electronics these days, you use a micro controller in some way at times, good thing to learn. 

First you learn now to use and work with micro controllers.
Part of the learning is to learn how to program the micro controller.
Firmware is just a program loaded into the micro controller.

You break a huge program into small steps. When all the needed small steps work properly you have the huge program.

A program to read an encoder is not a huge first step past the blink an led program.

Do some searching on the web.
 

[Rob Sims]

Thanks C, yes I've started researching.