Inductosyn / Resolver? - Pico's Resolver to Quadrature Converter

I have a question about the Inductosyn positioning system by Farrand Controls. I know the system is similar to a resolver but I wondered if anyone knew how similar. The analog to digital board they sell now has the ability to convert resolver signals as well as their Inductosyn transducers. 

I have a rotary indexer that has one of these systems. It had a "Sense Amplifier" hooked to it but other than that and the name 'Bendix" branded on the board there was no other information(except for the last pot adjustment was noted). The numbers found on the board do not provide any results for me yet.



I was hoping Jon might see this and chime in on his experience with Inductosyn if any. And shed light on whether he thinks his resolver converter might work for me. I have embedded a motor encoder for now but would like to get something back on the rotary itself.

Thanks, Ben

   

I tried to make a version of my resolver converter that would work with linear inductosyns, but could not get it to work. Possibly the 10 KHz excitation of the chip I was using was too high. I also had to drive it with lots of current, so that may have caused a 90 degree phase shift. Anyway, it just didn't work.
Jon

HII have some experience with Farrand inductosyn transducers. I converted a 5 axis Mitsui Seiki machine 2 years ago. It had a dead Fanuc system 9 on it. The fanuc system did the conversion i assume to a digital signal on one of the cards, but i could not figure out that part.In the end i purchased two Farrand 220100 converters on Ebay, read the documents and it worked, but i must say it is not a simple setup. 

Your photo above show the pre-amplifier. it amplifies the (very small) analog sin/cos signal before going to the converter board. there should be two of them if you want to use the 220100 converter. I met an experienced guy locally earlier this year who have been doing Fanuc and Siemens retrofits for 40 years,  told me that the resolver converters will not work on these because they are "low inductance" I cannot say more about that though, a bit beyond my knowledge base.....

Attached is the manual for the Farrand 220100 i used. Note that you need to buy the connector card as well, not sure what the number is for that, there are some on Ebay, as well as 220100 cards. You also need a very stable 15, 0, -15V power supply for this.The 220100 card provides a 10KHz excitation signal, reads the amplified sin/cos feedback and interpolates them to provide a quad signal with z pulse.

Regards
Henk

Answered my question and got me pointed in the right direction. I couldn't ask for more.

Mr. Elson and Henk, Thank you

Ben

This one might be worth looking at.
Farrand rotary systems are very accurate and work well. I don't remember how much trouble the slip ring units are, but  the transformer coupled units ere bulletproof.

I love this editor.