Can I replace one stepper with a servo?
The Z stepper on my 4X8' machine is going bad. I want to upgrade all of the steppers to servos but that's a big cost and I'd like to get back up and running quickly. Is it a problem to replace just the bad Z stepper with a ClearPath Servo and related power accessories to drive it? I'm already getting ready to make the switch from Mach3 to Mach4 and replacing my current controller with a ESS & BM3 combo so I've got some work to do anyway. I know doing them all at once would probably be one less headache in the long run.
Re: Can I replace one stepper with a servo?
Hi,
yes. Modern AC servos with Step/Dir position control behave almost identically to steppers. You will have noted the Clearpath have called their servos
'Stepper Killers' and their parts numbers are SDSKxxxxx etc to reflect the fact that that are drop in replacements for steppers.
There are a few differences between steppers and servos so there will be a learning curve.
Permit me to comment that Clearpath servos are expensive for what they are. I cast no aspersions to their quality but Teknics have made some very severe compromises
to get a servo that 'looks and feels like a stepper'. In particular Clearpath servos have only one digital output, whereas competing servos will have six, eight or more.
Additionally Clearpath has no auxilliary encoder output, unlike Delta and DMM, nor does Clearpath have an analog input for velocity or torque modes whereas Delta an DMM do.
Clearpath have low resolution (800 cpr) encoders as standard and 6000cpr encoders at special order. Even the basic Delta B2 series has a 160,000 cpr encoder and the A2 and B3 series
much MUCH more again. The last thing is that they are expensive. A 400W Clearpath is abut $517USD whereas a 750W Delta B2 series kit (servo motor, servo driver and cables) costs $438USD,
so twice the power for less and vastly better encoder and IO. Remember also that Delta drives and DYN4 DMM drives are direct off-line, ie 230VAC input, no power supply required.
Delta is a Taiwanese brand made in China. DMM is a Canadian brand made in China. Both are good quality, good support, good documentation and most importanly free set-up and tuning
software at fair prices. For your first foray into servos you'll want and need that set-up software.
I have five of these (750W Delta B2 series) plus others I'v bought for other machine retrofits, they kick arse!!
https://www.fasttobuy.com/flange-80m...er_p28084.html
Craig