7 day timer

thecliffman · Nov 7, 2002

I am new to plc programing and I want to run a 7 day timer to control 2 pumps, first 1 pump for 7 days then switch to the other pump for 7 days and so on. Can anybody help

PLucas · Nov 7, 2002

Thecliffman

What PLC are you planning to use?

What coding, if any have you done so far?

A bit more information would be helpful

Paul

Allen Nelson · Nov 7, 2002

Oh no, not again.....

Search for "FLIP FLOP" in this forum and the archives, and you'll find some code that will get you started. Just change "PB" for a seven-day timer, and you're in business.

You might want to add logic that checks that the lead pump has not failed to start, and to start the lag pump if it has.

"LEAD LAG" might also be a useful search.

labingtone · Nov 8, 2002

I have done a 7day timer before using PLC but it does not give a accurate 7 day. For Example I want to turn ON the pump at exactly 7 am every monday. The result is there is a delay in turn ON the pump and the delay become longer every time that the pump turn ON. What I did Is used solid state timer with 1 day duration and input this to the PLC. I used counter in my program to come up with 7 days time.

Mr. Allen Bradley · Nov 8, 2002

Witch plc's is used? plc5, slc, controllogix?

I suggest you using a 14 days counter. It's more easier for your application.

Your counter must count 0 to 13 days

0 = first sunday //// 6 = saterday
7 = second sunday //// 13 = second saterday

Programmed with a LIMITTEST instruction

First pump run's at days 1 to 5 and the second at days 8 to 12

It makes a Flip Flop

I wish help you

DRThorne · Nov 8, 2002

Keep it simple

Sounds like a simple control scheme, I wouldn't use a programmable controller for this. Theben http://www.theben.de.com makes a 2 output 7 day programmable timer for about $200.00 (CDN) and it's very easy to program and change your times. I think Luminite Control is the distributor in the US

Tom Jenkins · Nov 8, 2002

Most PLCs that have a real time clock have a day of the week register you can access. For the A-B SLC-500 and MicroLogix, for example it is S:53. Check your documentation.

Roy Robbins · Jan 5, 2003

Why not use a Siemens LOGO? It was designed for exactly what you are asking. For a few hundred bucks, you get the display and multiple cams and multiple clocks. It's modular and uses add-on I/O and standard programming. It can have analog I/O also. Any Siemens Automation distributor can help.

ricacorral · May 29, 2012

Thanx

Lancie1 · May 29, 2012

Thanx

A thank-you delayed 9 years is still better than none at all!

7 day timer

thecliffman

Member

PLucas

Member

Allen Nelson

Member

labingtone

Member

Mr. Allen Bradley

Member

DRThorne

Member

Tom Jenkins

Lifetime Supporting Member

Roy Robbins

Guest

ricacorral

Member

Lancie1

Lifetime Supporting Member

Similar Topics