I wonder if the six wire one is single ended and there are just 5v, 0v, A, B and Index and the extra wire is the shield?

If not then it could be it does not have the Index either connected or it has no index at all. Often the code number of the encoder will give you info on its signals etc, what is it?

Really a dual trace scope is the way to find out what is what.
Hood

Sadly nobody local to me that I know has a scope here is an image of the encoder showing the numbers. Does this give you any info?

That tells me it has an index pulse so I suspect it is just a single ended encoder. It is the ABZ part that tells me that, ie A channel, B channel and Z channel, the Z being the Index.
Also it looks like it may just be a 254 line encoder.
How many encoders did you get from Forbes in total?
Hood

Ok I just found some info from BEI that looks similar and also rings a bell with what I scoped when I tested that encoder.
Red is +5V
Black is 0V
Green is case Ground

So if that checks out then

Yellow looks like its channel A
Blue looks like its channel B
Orange looks like its channel Z.

But as said its a low cound encoder, only having 254 counts per rev or 1016 quadrature.

Hood

I got 4, two this type, the other like this was physically broken. So I only had 3. Is this no good for me then?

Yes it will work, its lower count than I would like but will still be fine. I would put that one on the Z.
It is also single ended so personally I would make up a line driver to make it differential, you can also buy the line drivers, think www.cncdrives.com sell line drivers ready made fairly cheap.

Do the colours check out, well Red Black and Green anyway as without a scope you wont really know the others. However if  they are correct then its likely the others are.
Hood

That's good news. I'll put this on the z axis.
I'm very eager to test and setup the machine. Can I use this encoder without the line driver until it arrives?

I've identified red as 5v and black as ground. Can I damage anything if I connect the rest wrong?

Ok I just found some info from BEI that looks similar and also rings a bell with what I scoped when I tested that encoder.
Red is +5V
Black is 0V
Green is case Ground

So if that checks out then

Yellow looks like its channel A
Blue looks like its channel B
Orange looks like its channel Z.

But as said its a low cound encoder, only having 254 counts per rev or 1016 quadrature.

Hood

Sorry only just noticed you posted this. So 5v and 0v(black) I'll check ground when I head back to workshop in 30 mins.

So how would I connect this to my ip-a without line driver, or can't i??

The green is case ground, so I hope the rest are correct too. The wires inside look very factory with nice connector, so I guess it's original. With less wires, in unsure how to connect these to my ip-a controller?

You would only get a run away situation if they were connected up wrong but the CSMIO is smart enough to sense that and should stop things very quickly.

I am not sure if it will work well without the differential but if you just connect the A B and Z to the  A+ b+ and i+   you will soon know.
Hood