What exactly am I using the Amp for? 100Vdc only or do I still need tach input?

You will be using the amps to control the motors exactly as they are/were used. With the original setup the Bandit received the resplver signal from the motor which allowed it to know the position of the motor and thus it could send out a voltage to the amp to move the motor one way or the other. What you need for the Kanalog is an encoder signal so you need to replace the resolver with one but it will do just the same as the bandit did, ie monitor where the motor is and send out a voltage to the amp to make it move to where it is meant to be.
I would imagine your amp requires a tach signal so you will have to keep that.
Hood

Ok so I figured out how to explain my previous post a little better:


That label is describing the terminal strip below.
Signal 1-6
1,2 X 2.25VDC
3,4 Y 2.13VDC
5,6 Z 2.39VDC

Tach 8-13
8,9 X -1.19VDC
10,11 Y 1.17VDC
12,13 Z -1.32VDC

Enable 14,15
-0.01

Signal wires are where the control sends the +-10v to control the axis, it will depend on feedback and position as to what voltage is being sent.
Tach is the voltage from the tach and will be so many volts per 1000rpm, if the motor is stationary you sould not get any voltage between pairs.
Enable is a voltage from your control to enable the power stage of your drives, I would imagine it would be 24v but you would need to check the manual. You should not get anything there unless the control is powered up and in a ready state.
Hood

When I power on everything the motors are all just running constantly. I'm wondering if it would be cheaper to maybe buy a better replacement instead of having them repaired. I saw some advanced motion control 12a8 4 for 400 and that would be enough for my x y z and 4th axis. What do u think? http://item.mobileweb.ebay.com/viewitem;PdsSession=1c6123421380a47a1213e1a3fffc6293?itemId=130583622486&index=2&nav=SEARCH&nid=56905275030

http://www.artisan-scientific.com/info/Advanced_Motion_Control_12A8_Datasheet.pdf

You really need to get things hooked up to the new controller before you can tell. It is very likely that the Bandit is screwed and thus your amps are reacting to signals from it.
Sad thing is you have resolvers on the motors so you will first have to replace them with encoders as although the Kanalog can take resolver signals the reply from Dynomotion on the effectiveness of resolvers didnt sound too promising.
The contraves amps are decent amps, I had the NC700's on the Beaver mill when I got it and the reason I went with different motors/drives was mainly because at that time (23 or 4 yrs back) there were not the options for devices that could control analogue amps and work with Mach. Things have changed and there are at least 4 options now, you have one of them so you should be fine. The only other thing that I disliked about the Contraves amps was they whistled loudly, it seems to be at a frequency that either you get driven daft by or you hardly hear it, I was the former.

You could hook up a battery box to the amps to test them out, what that entails is disconnecting the signal wires from the amps then hooking up a 9v battery that goes through a pot, you can then make sure the amp is enabled and then increase or decrease the battery voltage via the pot and the motor connected to that signal should react according to the voltage.



Hood

I found some encoders but they r $230 a piece is that overkill. What is a pot?

Potentiometer ?

Yes pot is a potentiometer, basically you are just wanting to supply a voltage to the drives that you can vary from zero to 10v (or 9v if using a battery) to test them out. I made up a battery box a while back out of 2 x  9v batteries and a pot, this allowed me to get 0v at centre of pot rotation and -9v fully one way and +9v the other. That way I could test out the amp in both directions. I now use that amp on the spindle of a manual lathe. The headstock on that lathe was extremely noisy so I used a servo direct to the spindle to bypass the noisy gears and just use a pot for spindle speed.

The encoders for you is a problem as you require the tach for your amps. Most people go the route of using Step/Dir capable drives and thus they dont need the tach so can replace that with an encoder. As you have the original amps then you will need to keep the tach.If you can get a belt and pulley mounted on the shaft you could drive a cheaper encoder that way and still keep the tach on the other end or if you could mount the encoder on the opposite end of the ballscrew that would also work, if not then the encoder you found that is compatible with the resolver mounts may be the only way unless you wish to first try the resolver inputs on the Kanalog to see if they are any use.

Hood

So I just went to Fry's electronics and bought 3 pots cuz they were so cheap and I didn't know which to buy 1k 10k and 50k ohms and a 9V