Hi,
I use 750W Delta B2 series servos on my machine, and a number of retrofits that I've done.
https://www.fasttobuy.com/flange-80mm-239nm-ac-motor-driver-kits-with-3m-cable-220v-075kw-cnc-servo-motor-for-cnc-router_p28084.htmlThey have a 160,000 count/rev encoder, 2.4Nm(rated), 7.1Nm(overload),3000rpm(rated), 5000rpm(max). They are AC servos, so all the bells and whistles. Delta
provide free setup and tuning software, which is a must have if you've had little or no exposure to modern servos. They are $438USD per kit (servo, drive and cables).
They do not require a power supply, they hook direct to the 230VAC line, easy.
You might like to consider that replacing the entire servo and drive might be an easier way to go. Many people have tried to get old school DC servos to run using all manner of different
drives and often encounter either compatibility issues or tuning issues. Buying a new and matching servo and drive obviates those sorts of issues.
Before you spend big dollars on the drives and/or braking units you really need to answer the question ' what is the likelihood that this purchase will adequately drive these servos?'
If the answer is not 100% confident then there is a risk that you'll end up with a sub-standard result....and after spending good money would be extremely disappointing.
I do recognise that its likely more expensive to replace the servo and drive, but the certainty of the outcome is appealing. You may also find some other 'twat' who wants to buy
the old servos and defray the extra spent on AC servos, there is a 'twat' born every minute!
Craig