Thanks for the quick response Neale, I did read the original question some time ago on the em/am drives but didn't see the one from last week (still doesn't answer the question really except it's just better or an improvement [product development])

Jazzcnc thanks very much perfect answer (just 882 or 806 decision now and as it's direct drive may end up 806 with your write up)

I guess I'm asking as there are a fair few 882's on ebay but not the 806's and the 882's can be got for about £60 inc p&p but can't find the 806's less than £90 per drive hence £120 on 4 drives is a fair premium for the new model that appears the same as the old one.

No disrespect to zapp, but they are not listed as a distributor hence probably have a modest second tier profit margin after buying from a distributor (although there costs are not actually that high considering you get them in a few days not 4-6 weeks). I'll probably buy them from them after the christmas break but thought I'd sound out on here before taking the plunge and learn something.

With regards to the current yes I'd expect some variance given the meter (fluke 88) was set on dc amps and although the the drive signal is pwm if it's a 50% duty cycle over the two stepper coils (a & b) then I would expect the primary current to the drive to be fairly close to the demand. I'd also expect the switching frequency to be quite high so almost akin to peak given the rms value will

I tried to put the scope (fluke scopemeter 97) across the current sense resistors of the tb6600 drives but did not get a good reading in the time I had available (this is a hobby at home)

Not trying to be a smart a{#%^ just hoping to learn something and dispell some of the conflicting info out there as every tom dick and Harry seems to have a cnc of some sort these days as I know little thought I'd learn something too thanks for your time