If your drives/amplifiers are connected to a Heidenhain 150B then I will presume that the encoders will be sinusoidal and thus no use.
 If however your control is  a 150BR then it will have square wave output encoders, whether differential or single ended I cant say.
Regarding +/- 10v, then yes that will be the control signal they take.
I dont know what drives/amps you have so cant really say whether they have encoder outputs but I would guess that they dont as it is really only AC Servo drives that tend to have them.

Hood

Thanks again for getting back to me on this. Would I be correct in thinking it's the role of the encoder to report back the current position of an axis to the controller? Can the encoders be replaced for the correct type for a modern controller.

If you were me, ( or is it my only option) to replace my servo drivers too?

Sorry for all the questions.

Thanks

Jim

I forgot to say its deffo the 150B controller which I have.

Yes you can replace the encoders with suitable ones.
The amplifiers will likely require a tach signal from your motors and if it is the type of DC servos I have seen that will be built into the motor (second set of brushes) So keep the tach and fit new encoders and you would be fine.

What make/model are the amps/drives?
Hood

Sorry to be so lame, I assume the drivers and the amp are on the same board? I also guess these are the devices at the bottom of the cabinet? I'll take the side off an have a look in the morning

Yes thats correct, amps are what the older drives are, basically just amplifiers, ie they receive a voltage signal and amplify it to send a higher voltage to the motors.


Hood

I've just took the side of the machine and the servo drivers are

Bosch Servo Drive Heidenhain Controller PN Z15-1-240V

Does this help at all?

Do you have any documentation on the drives at all?
Hood

Sadly nothing

There doesnt seem to be much info around about them but I did find an extract from the manual which has some info.
http://www.pennineuk.com/library/pdf/boschZ15Manual.pdf

Hood