how to use an external programmable timer switch as a PLC input??

hello, am doing my FYP using the PLC, am automating some process, so i want to use an external programmable timer as an input. so at the specific time the timer will triggle the input and therefore activating the desired output.
so far most of the timers switch that i found in the shops are AC timers, so i need any help about this i juz need a timer that work as an input for the plc, rather than the internal plc timer which is not synchronous.
i would appropriated any help as soon as possible

You need to tell us more about the PLC you plan to use, as well as the timer. We like part numbers here.

What do you mean when you say the "internal plc timer which is not synchronous". Synchronous with what?

am using omron plc to simulate my prototype,,
i want to control 4 elecronics valves that release water from a tank
i want the valves work on a specific time evry day without any manual operation
that why i want to use a programmable timer switch, not the plugg-in timer but the timer with input and output wires that can be connected to the plc input section and com.
what i mean from "internal plc timer which is not synchronous" that it is not synchronous with our real life time, it does nt has a built in watch.
so how i can solve this??
thanx for your reply

sharif ba'asher said:

am using omron plc to simulate my prototype,,
i want to control 4 elecronics valves that release water from a tank
i want the valves work on a specific time evry day without any manual operation
that why i want to use a programmable timer switch, not the plugg-in timer but the timer with input and output wires that can be connected to the plc input section and com.
what i mean from "internal plc timer which is not synchronous" that it is not synchronous with our real life time, it does nt has a built in watch.
so how i can solve this??
thanx for your reply

Click to expand...

Pretty well all Omron PLCs have a descent Reat Time Clock. So, I am not sure why you would want External Timers. In any case, as requested by OkiePC, we would need more specific information. Which Omron PLC, and which Timers are you planning to use? Exact part number please.

Good information and clear questions are required for good answers.

Stu....

Okay, so you are using an external real time clock to send a pulse to the Omron PLC so that your sequence is triggered daily and the time set by the user on the real time clock relay. This makes good sense.

What is the part number of your Omron PLC?

What is the mfg and part number of your timer?

Yes, "reading your plc's real time clock and setting an output in desired time" is better idea.

@Sharif

Look at these:
Moeller EASY or Siemens LOGO. Invented as timers and developed to small PLCs.

Perhaps they can do the whole job.

http://www.klocknermoeller.com/easy.control/index.htm

http://www.automation.siemens.com/m...oller/en/logic-module-logo/Pages/Default.aspx

Kalle

right now am not sure of my PLC specifications, but i guess it is omron CPM2*,
first it has no real time clock as my supervisor told me
so my idea to use an external timer switch came from there.
MR Okie i have not find a suitable timer yet, and this is the problem now
At first i though that i need some timers that send signals to the plc at specific time but i found that i juz need a wire that connected from the input to the com through the timer switch, so the timer is connecting(at the preset time) and disconnecting the connection betwen the input and the com. plc input is jus need a contact to be on.
i found many timers which is ac timers ( Hager timer switch 230v ac~) am nt sure whether it can work or not, i guess it need to be powered, but for my case i jus need something that make the contact between the input and the com without any ac or dc power,, so i really dnt knw, am nt experienced with this stuffs and i need your help in solving the timer prb, my time is too short, i should finish and simulate my prototype this this week. thanx

if u're sure that plc doesnot have clock.
u can use several "on delay timer".strange way but, u can use 12 on delay timer each of them 2 hours. do u want one output in one day? u can set it once, 24 hours later it'll set again,24hours later again....

Hello Mr. Sharif Ba'ashar, I assume your PLC runs on electricity?? So why can't you source an external timer that has the same input voltage as the PLC's power supply ?? Then as you mention use the 'dry' contacts for you application.....

I would not even consider using the CPM2 - use the CP1L.

@ peanutz
further explanation pls,, how am goin to use a 230v~ as input for my plc, i want the connection to be from the input to the com through the timer so i guess the 230 v will go to the plc as a load for the timer!!!

For daily operation, use a time switch instead of a standard timer. See this one from Omron.
As you can see, it has a separate contact for the output. For both timers and time switches, you don't have to worry about the voltage of the power source. The power source is just the power source. It has nothing to do with the output.

Sharif, use 230V to supply the timer only. Then use the timer's contacts to switch the PLC common rail to your input.

thank to all of you all your ideas was great an useful,
@ keithkyll i saw that product and i ve found it here in malaysia, but it is a bit expensive( its over the project budget) @peanutz so i found another time which am goin to buy tomorrow. but am still not sure wheter it can work with my PLC or not
this the timer i found , pls feed me back, can i use the output as a volt-free contact??
the connection of the output to the same input's neutral (N)vis confusing me!!
http://www.theben.de/en/Home/Products/TIME/Analogue-time-switches/DIN-rail/Daily-program/SUL-181-d