Need Instruction Set Reference for Symax Model 300 PLC

Hello everybody! I am working on upgrading an exisiting PLC system comprising of a Symax Model 300 PLC. I am replacing it with an Allen-Bradley ControlLogix. I have a print out of the old program (thanks to OZEE) and there are a few instructions in it that I cannot understand completely. For example there is a timer which has some input logic conditions to start the timing (like all other timers) but it also has the line connected directly to its "clear" input. There is another timer that has similar connections where the only difference is that it has some logic to trigger the "clear" bit. I have no clue about how these timers are operating.
It would immensely help to have an instruction set reference for the Symax PLC. If anyone has anything please share it with me. I would not mind paying shipping charges for a hardcopy.

Thanks fellas,

I appreciate any help I can get.

All SY/Max timers have two control lines. The top line (HOLD) can be used for strt/stop control with out clearing the timer. The second line (CLEAR) clears and resets the timer.

For standard timing (maybe 90%+ of the time) the top line is a direct short to the power rail and all of the control is done on the middle line.

Square D has a tech library with most of the old Sy/Max literature.

puravdagli said:

Hello everybody! I am working on upgrading an exisiting PLC system comprising of a Symax Model 300 PLC. I am replacing it with an Allen-Bradley ControlLogix. I have a print out of the old program (thanks to OZEE) and there are a few instructions in it that I cannot understand completely. For example there is a timer which has some input logic conditions to start the timing (like all other timers) but it also has the line connected directly to its "clear" input. There is another timer that has similar connections where the only difference is that it has some logic to trigger the "clear" bit. I have no clue about how these timers are operating.
It would immensely help to have an instruction set reference for the Symax PLC. If anyone has anything please share it with me. I would not mind paying shipping charges for a hardcopy.

Thanks fellas,



I appreciate any help I can get.

Click to expand...

Here is a link to the programming manual. Timers are in Chapter 15
http://ecatalog.squared.com/techlib/docdetail.cfm?oid=090089268010779d

This is really good information Jim. Sadly, I need some more of it. Here is two rungs from the program that are worrying me the most. Can u help me decode them?

|
|
|---][----][--------------------------------------------]TIME |
| | |
| |T6 |
| | |
| | |
| |s0035 |
| | |
| | |
| | |
|-------------------------------------------------------] |
| | |
| | |
| |0.1M |
| | |
| | |
| |=9999 |
| | |
| | |
| |T6 |
| | |
| |0104 |
| |--()--|
| *--06--*

The next rung is,

| T6 T6
| OUT
|
|+--------------------+ 0022
[]IF S0035 >S0085 [-------------------------------------()----
|+--------------------+ 06

What do these mean in Allen Bradley terms?

I cannot find the address S0035 (nor S0085) in the cross reference or the tag list. What do these addresses mean?

The manual has instruction set for the models 300, 400, and 600 processor. It references SFW472 programming software, but the timers are the same for SFW472 or SFW374 programming software.

****...it took all the spaces out......i shall retype it in word and attach the file...

Peal you are a life saver man!

Sy/Max uses a single set of memory locations (they are called storage registers and abbreviated S) for all timers, counters, and math operations.

So your timer is using register S35 to keep track of the accumulated time. Because the timer block can only reference a fixed value (in your case 999.9 minutes) it was common practice to use a dummy output (in your case 104-06) and then add a second rung to provide the actual control function. Your second rung says that if the accumulated timer value (S35) is greater than or equal to a memory location (S85) then turn on the coil 22-06. Register S85 may not be contained elswhere in the program, it may be written to from an HMI.

Symax Timer

I realize this is an old thread, but I've run across an old SY/Max PLC and need to upgrade it to an AB ControlLogix. The timer function is a bit confusing to me as well. After reading this post, it is a little clearer, but am I still unsure of some things. The bit that is a coil at the bottom of the timer in my timer it is 0411 04. Does this bit come on when the timer is done?

So to transfer this to an AB timer, I would use a RTO timer and have it run all the time. The bit that is connected to the CLEAR line on the Sy/Max timer would reset the timer in AB and the done bit would turn on the output 0411 04? Is that correct?

barbarawhite said:

I realize this is an old thread, but I've run across an old SY/Max PLC and need to upgrade it to an AB ControlLogix. The timer function is a bit confusing to me as well. After reading this post, it is a little clearer, but am I still unsure of some things. The bit that is a coil at the bottom of the timer in my timer it is 0411 04. Does this bit come on when the timer is done?

So to transfer this to an AB timer, I would use a RTO timer and have it run all the time. The bit that is connected to the CLEAR line on the Sy/Max timer would reset the timer in AB and the done bit would turn on the output 0411 04? Is that correct?

Click to expand...

I'm in the midst of similar project! I'm trying to figure out the SyMax timer function too, and converting to AB Control Logix. Maybe we can share notes/information? I've not been able to locate any instructions manual for programming, only for the physical controller itself. Find it here: https://www.schneider-electric.com/...e/FAQS/242000/FA242875/en_US/30598-503-01.pdf

Symax manual

I did find the manual, but I can't upload it. I tried to just upload the chapter on the timers and counters, but it's still too big.