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 November 14th, 2006, 10:13 AM   #1
Stauby
Member
United States

Stauby is offline
 
Join Date: Jan 2005
Posts: 3
ML 1100 High Speed counter- 1 or 4?

Hi all, I have a simple application that I intend to design around a Micrologix 1100. The hitch is that I have two 5khz inputs that I wish to count. I am confused on the wording in the selection guide- it states theat there is 'one embedded 20khz high-speed counter' on one page, but later states under 'High-Speed Inputs (pulse catch)' that there are four @ 20khz. I am not familiar with the pulse catch inputs; can I use any combination of the 4 to consistently see the two 5khz channels?

If this won't fly, any leads on remote high speed cards that will interface with the 1100 will be greatly appreciated.
  Reply With Quote
Old November 14th, 2006, 11:53 AM   #2
pimpim32
Member
Romania

pimpim32 is offline
 
Join Date: Mar 2003
Posts: 115
if you want to use them simultaneously it is 1. you have four inputs to use them as you wish, but when comes to counting if you count in same time they will overlap resulting in losing counts.
that's why they are saying you have only HSC.

I might be wrong for 5Khz, but I tested for 10Khz on ML1500 who has 8 high speed inputs but only 2HSC files by default, and with a good reason. when I tried to count 4 HSC in same time for arount 10Khz I lost counts.

If you won't use them in same time is ok.

You have HSC module for ML1500 but the problem with it is if loses power loses counts. it is not battery backed-up.
1769-HSC High-speed Counter Module
  Reply With Quote
Old November 15th, 2006, 07:50 AM   #3
Stauby
Member
United States

Stauby is offline
 
Join Date: Jan 2005
Posts: 3
I did buy the 1769 HSC card but it is a different form factor and according to AB is not compatible. Is there a way to use it as a remote device? I just need to do some simple switching - for example, count 6000 pulses and turn off a motor- so if there is a simple logic device that could handle it internally that would be fine. I looked extensively and am surprised there isn't a Red Lion or similar counter that can accept a preset from a remote device, that would be about perfect for the job.

Thanks again for any advice.
  Reply With Quote
Old November 15th, 2006, 08:27 AM   #4
Ken Roach
Lifetime Supporting Member + Moderator
United States

Ken Roach is offline
 
Ken Roach's Avatar
 
Join Date: Apr 2002
Location: Seattle, WA
Posts: 8,563
The MicroLogix 1000, 1100, and 1200 have only one hardware high-speed counter.

The MicroLogix 1500 has two.

I think you need the MicroLogix 1500 controller for this application. Ordinary counters or fast pulse-catch inputs won't successfully read a 5 kHz signal, but the hardware HSC circuits will.
__________________
"Intelligence is the capacity to know what we are doing and instinct is just instinct. The results are about the same."
  Reply With Quote
Old November 15th, 2006, 10:00 AM   #5
pimpim32
Member
Romania

pimpim32 is offline
 
Join Date: Mar 2003
Posts: 115
If you bought the 1769-HSC I guess you can by the ML1500 to go with and you are set.

Is far as i know 1769-HSC goes only on backplane for ML1500 and Compactlogix

So, if your inputs are not in same time, you can use ML1100 - one HSC file and one EII file.

If you use them in same time i will go with ML1500 - two HSC
(not to mention that you already have the 1769-HSC module)

I do not understood what you mean RedLion counters do not accept preset from a remote device.

From what you said till now looks like the C48C will be good for you.
  Reply With Quote
Old November 15th, 2006, 10:18 AM   #6
Ken Moore
Member
United States

Ken Moore is offline
 
Ken Moore's Avatar
 
Join Date: May 2004
Location: Upstate South Carolina
Posts: 2,325
Quote:
Originally Posted by Stauby
I did buy the 1769 HSC card but it is a different form factor and according to AB is not compatible. Is there a way to use it as a remote device? I just need to do some simple switching - for example, count 6000 pulses and turn off a motor- so if there is a simple logic device that could handle it internally that would be fine. I looked extensively and am surprised there isn't a Red Lion or similar counter that can accept a preset from a remote device, that would be about perfect for the job.

Thanks again for any advice.
Take a look at Durant, I have a few installed, where the PLC sends an ASCII message to the Druant for the preset and source.
__________________
"To give real service you must add something that cannot be bought or measured with money; and that is sincerity and integrity."
- Donald A. Adams

  Reply With Quote
Old November 15th, 2006, 01:28 PM   #7
Sergei Troizky
Member
Canada

Sergei Troizky is offline
 
Join Date: Oct 2004
Location: Montreal
Posts: 522
There are four input interrupts available on top of the HSC in ML1100.
They may be configured for inputs 4 to 7 and user programmed for counting.
But I am not sure about ability to count 5kHz without lost interrupts.
I would arrange a diagnostic loopback on the ML1100 and count PTO pulses by the interrupt, in order to find the top frequency limit without lost counts.
It will also somewhat depend on the main program size and organization.
Try to keep rungs short and increase the watchdog timer setting to acceptable maximum.
  Reply With Quote
Old November 20th, 2006, 06:48 AM   #8
Stauby
Member
United States

Stauby is offline
 
Join Date: Jan 2005
Posts: 3
Great tips. My program will be small and primarily error handling. It looks tight but I may be able to swing reading the pulses.

I'll look more into the ascii and RS-485 options in case the timing doesn't work out.
  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

Similar Topics
Thread Thread Starter Forum Replies Last Post
Micrologics 1100 High Speed Counter (HSC) 46swimmer LIVE PLC Questions And Answers 8 March 29th, 2012 03:39 AM
Shaft speed counting with Micrologix 1100 high speed counter. tribologist LIVE PLC Questions And Answers 5 October 23rd, 2006 02:12 PM
High Speed Counter on FX0S sara LIVE PLC Questions And Answers 2 November 11th, 2004 09:15 AM
AB Micro High Speed Counter Trouble Rocky Cortis LIVE PLC Questions And Answers 2 September 19th, 2004 01:09 PM
high speed counter confusion schick LIVE PLC Questions And Answers 6 July 24th, 2002 06:00 PM


All times are GMT -5. The time now is 09:24 AM.


.