Mick

Sounds like the repair is your cheapest option, at least in the short term.

I'm not sure if you realise that ac servo drives would typically be mains powered, so would not require a complex power chassis like the one you currently use.  You would only need a +24V logic supply for the CSMIO and the drive logic circuits. Drives can be programmed for either analogue +/-10V or step and direction inputs. The former would allow you to use the CSMIO that you already have. I personally prefer the screened construction and 24V logic of the CSMIO to the bare board presentation and 5V levels of the cheaper alternatives.

Allan

Hi Allan

 Thanks for that info and great to know I can still use the CSMIO. I have emailed Norwin and asked them to repair the drive anyway. I can't sell a drive that doesn't work. Yes, I agree that the CSMIO is an industry standard 24v controller that is not open to the elements which is another reason I liked it.

If I decided to go down the AC route what drivers and motors would be a good choice? Craig has mentioned some possibilities in previous posts and I will look into those over the next few days.

Cheers
Mick

Mick

If you ultimately switch to ac drives, one thing is very important: use matched drives and motors from the same manufacturer. In that way, the drive will be pre-programmed with all of the salient motor parameters.

I have found the Chinese Kinko drives to be of good quality, well designed and reliable. I use their CD422A drives, which can be paired with servos up to 750W. Motors are equipped with decent circular connectors and good quality cables of 3m and 5m lengths are available for this connection. These drives are very flexible and can be programmed either from their panel or via a free PC application. One caveat: you need to be adept at fine soldering as there is a minature 36 pin I/O connector that needs to be soldered.

Allan

Hi,

If you ultimately switch to ac drives, one thing is very important: use matched drives and motors from the same manufacturer. In that way, the drive will be pre-programmed with all of the salient motor parameters.

So true, my Allen Bradley servo has a PC apllication that loads the servo data straight into the drive, it has all the
usual resistances and inductances but also has a peicewise linear approximation to the magnetic hysteresis properties
and also includes a thermal model......just brill! They are SO FAR AHEAD of brushed servos it just has to be experienced to
be believed.

Craig

Hi,
if you are going to continue to use the CSMIO-A as controller then the CSMIO MUST read the encoder
to close the position loop, therefore any servo that has a serial encoder will not work with the CSMIO.

As it turns out there are still plenty of servos with quadrature incremental encoders out there, 2500 line
or 10,000 count is entry level these days. The DMM's I alluded to have a 16 bit incremental and would work
with the CSMIO. Not sure about the Delta 17 bit encoders and even less sure about Delta's 20 bit absolute
encoders. Quite frankly the trend to serial  multi turn encoders is already underway...I think in ten years time you'll
only find incremental encoders on old plant.

As I have already said in this thread; servo drives are becoming increasingly sophisticated and closed loop
capable motion controllers are falling by the wayside.

Craig

Hi Both

Thanks for all the info. I will work some costing out for both drives. As far as sizing the motors to what I have. The specs in the manual for the Sem motors doesn't give any KW rating. If I go off the motor plate its states at 130v the motor will turn at 4000rpm and demand 37amp.
This works out to 4.8kw??? Surely my calculations are not right. When the motors we are talking about are around 700 watts.

Allan

Where did you buy the Kinko drives.? Are you using Kinko Motors?

Cheers

Mick

Hi Mick,

Where did you buy the Kinko drives.? Are you using Kinko Motors?

That is exactly what Allan commented about....the desirability that the servo and drive be from the same manufacturer and matched.

There are drives, Granite Drives for one, that are intended to be applied to a range of servos and they do a good job. I doubt they could ever match
a drive and motor from the same manufacturer/ design team.

Craig

Hi,
I suspect that the peak power might be 4.8kW but a continuous power of 1/4 or less, about 900W.
A 750W or 1kW AC servo would be a good match.

Craig

Hi Craig

Are you using an Allen Bradley motor to match your drive?

Cheers
Mick

Mick

I purchased the Kinco drives and motors from Zap Automation in the UK.

Allan