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Showing results 1 to 18 of 18 Search took 0.00 seconds. Search: Posts Made By: Peter Nachtwey

Forum: LIVE PLC Questions And Answers February 8th, 2023, 10:10 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey Yes, I was sloppy. OK we agree. 0.2085... Yes, I was sloppy. OK we agree. 0.2085 cnts/250 microseconds. The problem is that most of the time the controller doesn't think it is moving and when it does, there is a huge output spike due the...

Forum: LIVE PLC Questions And Answers February 8th, 2023, 03:34 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey I am still confused. If an SSI encoder has 22... I am still confused. If an SSI encoder has 22 bits then it gets 2^22 counts per revolution. Next we need to know how many inches travel per revolution. From this we calculate the number of counts...

Forum: LIVE PLC Questions And Answers February 8th, 2023, 12:40 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey No! fewer! 41.7 cnts/inch / 20 inch/sec =... No! fewer! 41.7 cnts/inch / 20 inch/sec = 2.085 cnts/sec. This means that most of the time, the controller doesn't see the motor turning. When it does, the derivative term provides a big...

Forum: LIVE PLC Questions And Answers February 7th, 2023, 09:25 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey I 'be got a new topic for a Peter ponders pic... I 'be got a new topic for a Peter ponders pic video. Resolution.

Forum: LIVE PLC Questions And Answers February 6th, 2023, 09:55 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey The spikes are not really noise. They are due to... The spikes are not really noise. They are due to poor feedback resolution and the derivative gain. The controller has a scan time of 250 microseconds. Going slow will not help. I bet there...

Forum: LIVE PLC Questions And Answers February 5th, 2023, 11:43 AM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey What do you mean by control curve? The green... What do you mean by control curve? The green line should be the output to the valve. The valve has an inner control loop that should position the valve to 50% open when a 5 volt signal is applied. ...

Forum: LIVE PLC Questions And Answers February 3rd, 2023, 07:20 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey So the target and actual positions are not on the... So the target and actual positions are not on the same scale? The tracking looks good when moving.

Forum: LIVE PLC Questions And Answers February 2nd, 2023, 10:23 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey A direct output command would not have the spikes... A direct output command would not have the spikes in the control output. A direct output command simply sends a voltage to the valve. You need to be fast to turn the voltage back to 0 to keep it...

Forum: LIVE PLC Questions And Answers February 2nd, 2023, 01:05 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey OK, the trend is helpful but closed loop control... OK, the trend is helpful but closed loop control not open loop. Do you see the spikes in the control output? That happens because your feedback is too coarse. You don't have enough pulses per inch...

Forum: LIVE PLC Questions And Answers February 2nd, 2023, 12:08 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey is there slop in the chain? Also, hydraulic... is there slop in the chain? Also, hydraulic motors have a lot of stiction. You may need to use the dead band eliminator to keep from rocking back and forth. It is cold here too. 28 deg F and I...

Forum: LIVE PLC Questions And Answers February 1st, 2023, 05:01 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey The valve should be good. What you need to do is... The valve should be good. What you need to do is a manual job using the direct output command. This will show if the mechanics are tight. Also, there better not be hose between the valve and the...

Forum: LIVE PLC Questions And Answers May 24th, 2018, 07:54 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey I am not familiar with how the group update... I am not familiar with how the group update works. Seems slow. If this is the PLC scan time then no problem This is the coarse update 2000 microsecond or 2 ms. This is OK considering the...

Forum: LIVE PLC Questions And Answers May 24th, 2018, 05:14 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey That is 0.024 inches/count. That is too high. ... That is 0.024 inches/count. That is too high. If the resolution was 0.001 inches/count the output would change in steps that are 24 time smaller. The output would be smoother. That was one of...

Forum: LIVE PLC Questions And Answers May 23rd, 2018, 07:18 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey I looked at the new data. Look at the control... I looked at the new data. Look at the control output ( green ) notice how it changes in steps? This is due to course feed back but then I see you have a 22 bit SSI encoder that should provide very...

Forum: LIVE PLC Questions And Answers May 23rd, 2018, 12:44 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey Robb, the Rexroth valve you now have ( Bosch... Robb, the Rexroth valve you now have ( Bosch Rexroth is now Rexroth ) isn't satisfactory for motion because there is no spool feed back. The flow forces move the spool around. Page5/16 shows the...

Forum: LIVE PLC Questions And Answers May 22nd, 2018, 07:58 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey I don't have a lot of time to look at it right... I don't have a lot of time to look at it right now but the valve is garbage. If there is no Bode plot, the valve should not be used for servo applications. More on this later. I can't make out...

Forum: LIVE PLC Questions And Answers May 19th, 2018, 10:38 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey You need to ask others about how to get a trend. ... You need to ask others about how to get a trend. I know it can be done because I have seen it done in person. I haven't touched RSLogix software in 15 years. The screen display says units...

Forum: LIVE PLC Questions And Answers May 18th, 2018, 07:18 PM

Replies: 45 RS5000 and M02AS hydraulic servo motor Views: 10,179 Posted By Peter Nachtwey If the motor oscillates back and forth with... If the motor oscillates back and forth with stopped it could be from excessive static friction or a dead band in the valve. In these cases the actual position can not reach the command position so...

Showing results 1 to 18 of 18

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