You are not registered yet. Please click here to register!


 
 
plc storereviewsdownloads
This board is for PLC Related Q&A ONLY. Please DON'T use it for advertising, etc.
 
Try our online PLC Simulator- FREE.  Click here now to try it.

---------->>>>>Get FREE PLC Programming Tips

New Here? Please read this important info!!!


Go Back   PLCS.net - Interactive Q & A > PLCS.net - Interactive Q & A > LIVE PLC Questions And Answers

PLC training tools sale

Reply
 
Thread Tools Display Modes
Old June 21st, 2016, 07:44 PM   #1
Ken Roach
Lifetime Supporting Member + Moderator
United States

Ken Roach is offline
 
Ken Roach's Avatar
 
Join Date: Apr 2002
Location: Seattle, WA
Posts: 13,530
Slightly OT: Overspeed and Zero Speed detection

I have an application where I have to detect the start of motion (non-zero-speed) quickly, and also be able to detect overspeed of around 3000 RPM.

The sensor is a simple 60 pulse per revolution quadrature output encoder.

I've found devices that give me zero speed detection, and devices that give me overspeed detection. The IFM DD110S (overspeed) and DA102S (zero speed) and Rockwell MSR75 (zero and safe speed zone) have all been used by my co-workers.

But as far as I can tell, all of those have either zero-speed or over-speed or safe-speed-range detection. They don't do both zero-speed detection and overspeed detection in the same module.

And it doesn't really need to be a safety device; the functions are to protect well-guarded machine elements, not to protect people.

I can run these encoders into a motion controller, or into a MicroLogix 1400's high speed counter, if I'm willing to expand the budget. But my boss would prefer the simplicity of a dedicated purpose relay.

Any suggestions ?
  Reply With Quote
Old June 21st, 2016, 09:09 PM   #2
jdbrandt
Lifetime Supporting Member
United States

jdbrandt is offline
 
jdbrandt's Avatar
 
Join Date: Oct 2002
Location: Pennsylvania
Posts: 1,008
Quote:
Originally Posted by Ken Roach View Post
I have an application where I have to detect the start of motion (non-zero-speed) quickly, and also be able to detect overspeed of around 3000 RPM.

The sensor is a simple 60 pulse per revolution quadrature output encoder.

I've found devices that give me zero speed detection, and devices that give me overspeed detection. The IFM DD110S (overspeed) and DA102S (zero speed) and Rockwell MSR75 (zero and safe speed zone) have all been used by my co-workers.

But as far as I can tell, all of those have either zero-speed or over-speed or safe-speed-range detection. They don't do both zero-speed detection and overspeed detection in the same module.

And it doesn't really need to be a safety device; the functions are to protect well-guarded machine elements, not to protect people.

I can run these encoders into a motion controller, or into a MicroLogix 1400's high speed counter, if I'm willing to expand the budget. But my boss would prefer the simplicity of a dedicated purpose relay.

Any suggestions ?
Milltronics?
Anti-plugging switch?
__________________
Jeffrey D.Brandt
  Reply With Quote
Old June 21st, 2016, 09:16 PM   #3
gmferg
Lifetime Supporting Member + Moderator
United States

gmferg is offline
 
gmferg's Avatar
 
Join Date: Feb 2008
Location: Modesto, CA
Posts: 333
Pepperl+Fuchs brand, model: Frequency Converter with Trip Values KFD2-UFC-1.D I think this will do what you want. It accepts a pulse input and calculates a speed and provides an analog output representing the speed and has 2 programmable relay outputs that can be configured to trigger on a max speed and min speed. There are a lot more options that it can be programmed for.

Here is a link: http://www.pepperl-fuchs.us/usa/en/c...ystem-jumper-0
  Reply With Quote
Old June 21st, 2016, 10:22 PM   #4
Peter Nachtwey
Member
United States

Peter Nachtwey is offline
 
Peter Nachtwey's Avatar
 
Join Date: Apr 2002
Location: Vancouver, WA, US
Posts: 6,575
How fast is quickly? How accurate does this need to be? How fast is the speed changing? I have "mathemagical" equations.
__________________
"Living is easy with eyes closed, misunderstanding all you see...." Strawberry Fields Forever, John Lennon
  Reply With Quote
Old June 21st, 2016, 11:11 PM   #5
Ken Roach
Lifetime Supporting Member + Moderator
United States

Ken Roach is offline
 
Ken Roach's Avatar
 
Join Date: Apr 2002
Location: Seattle, WA
Posts: 13,530
I need to detect motion starting within about 100 milliseconds. It doesn't have to be very accurate; this is a torque control application that will be running a couple hundred RPM at the most, unless a coupling or mechanism breaks.

The main controller is a Delta Computer Systems RMC150, but it's handling six axes (analog command, analog feedback) already so I can't add enough encoder inputs to also handle this feature (I need six) using "Q" or "U" modules.

The Banner Safe Speed Monitor device ticks most of the boxes but I'm not sure it can respond quickly enough... I'll have to take a close look at the precision that's really required.
  Reply With Quote
Old June 21st, 2016, 11:27 PM   #6
sthompson
Lifetime Supporting Member + Moderator
Canada

sthompson is offline
 
sthompson's Avatar
 
Join Date: Jan 2007
Location: Vernon, BC
Posts: 1,816
Hi Ken:

Would something like this work for you?

https://www.phoenixcontact.com/onlin...01-03-01&tab=1

Stu....
__________________
There's never time to do it right, but there is always time to do it over!
No trees were killed in the creation of this message.
However, many electrons were terribly inconvenienced.
  Reply With Quote
Old June 27th, 2016, 12:15 PM   #7
schui
Member
Canada

schui is offline
 
Join Date: Sep 2011
Location: Toronto
Posts: 51
Hi,

Pilz S30 Relay and Safety Encoder

See Link below:
https://www.google.ie/?gws_rd=ssl#q=pilz+s30
https://www.pilz.com/en-INT/eshop/00...rotary-encoder
  Reply With Quote
Old June 27th, 2016, 02:07 PM   #8
Peter Nachtwey
Member
United States

Peter Nachtwey is offline
 
Peter Nachtwey's Avatar
 
Join Date: Apr 2002
Location: Vancouver, WA, US
Posts: 6,575
Quote:
Originally Posted by Ken Roach View Post
I need to detect motion starting within about 100 milliseconds. It doesn't have to be very accurate; this is a torque control application that will be running a couple hundred RPM at the most, unless a coupling or mechanism breaks.

The main controller is a Delta Computer Systems RMC150, but it's handling six axes (analog command, analog feedback) already so I can't add enough encoder inputs to also handle this feature (I need six) using "Q" or "U" modules.

The Banner Safe Speed Monitor device ticks most of the boxes but I'm not sure it can respond quickly enough... I'll have to take a close look at the precision that's really required.
Sorry for the delay. I was out of the office last week.
I am confused. The 6 axes provide velocities and accelerations every millisecond. There is even a stopped bit and a parameter for how "stopped" the axis must be before the stopped bit is set.
Are you talking about a 7th input? Configure it as a half axis so the same position, velocity and acceleration information is available for that axis.
You need to write a user program to detect the high speed. There is already a stopped bit feature included as part of the firmware.
Do you have a torque input? If so we have a speed or position with force, pressure or torque limiting modes.
The best thing to do is call us so we get get the best solution.
__________________
"Living is easy with eyes closed, misunderstanding all you see...." Strawberry Fields Forever, John Lennon
  Reply With Quote
Reply
Jump to Live PLC Question and Answer Forum

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 12:57 AM.


.