5TI Sequencer covert to S7

[Johnny T]

Hi,

I'm trying to upgrade an old Texas Instruments 5TI Sequencer to Siemens S7.

I've got a print out of the software but there are a couple of questions that I have.

The sofware refers to CR... such as CR368 or CR364, are these just internal markers. Could I just convert these by making CR368 into M36.8 and CR364 into M36.4 etc?

There is also a block that is labelled as MCR and has a 15 in it. Is that the Master Control Relay, as in S7? If so, what is the 15 for?

On the timers, some have an 'F' in them. Does anyone know what this denotes? Am I right in assuming that the timebase is 0.1 second?

I'd really appreciate any help with any of these questions. You would be saving what little hair I have left !!

 

[Ken M]

Johnny T,

Yes the CRs in the 5TI were just the same as markers (CR = Control Relays). Ms would be the ideal equivalent.

The 5TI MCR instruction was a Master Control Relay, but the number indicated how many following networks were affected by it. So the 15 in this case means the next 15 networks are governed by the MCR.

If memory serves me, I think timers in 5TI could have two timebases : 1.0sec or 0.1sec. A Fast timer (TMRF) had the finer resolution timebase. Be aware, however, be very aware with 5TI timers. The 5TI had no microprocessor. Its basic clock signal came from the incoming mains (yes, I know!!). So in a 50Hz installation a timer with the same apparent value would run slower than in a 60Hz installation. Also timers could vary throughout the day as mains frequency rode up and down. (Ah, kids these days, they wouldn't believe what you had to do to get a machine running. They've all got it too easy nowadays!) Your S7 will have a rock-steady timer chip in there making sure this doesn't happen, so don't worry about translating the preset values too literally - they may have had some free time built in by the original programmer.

Good luck and regards

Ken.

 

[David_Emmerich]

Ah yes the good old days of FLEX Timers...If its not just right now,either wait a while, or add a few dummy rungs that you could turn on and off to fine tune that scan time/time base.
David

 

[bernie_carlton]

The 5TI was my first experience with a PLC. I had never heard of them before. We had to draw out the ladder by hand and enter the instructions one at a time, following logic flow on little LED's. I once had to reenter a 500 instruction program that my partner had somehow dumped by beating on the Timer Counter Access Unit (???). I made it just in time without any errors for a machine startup. Then we finally got the tape backup unit for saving programs. We were in heaven! What a way to learn.

 

[Jay Anthony]

The time base of the 5TI sequencer was only 0.1sec. The long time base 1.0sec came in with 520/530. There was also a limitation of 50 timers per 1K instructions. You had to structure your logic so that the 51st timer was across the 1K boundary and into the 2nd 1K segment of memory.
Boy, that was a long time ago!

 

[Johnny T]

Ken, you are a star mate!

Thanks to David, Bernie and Jay for your help too. Seems like we had a little trip down memory lane there...

"Eeeee ! Those were the days !"

So, the number after the MCR is the amount of rungs governed by it. I'm also assuming then that the number after the JMP instruction is the number of rungs jumped (as there are no labels in the program).

I have another question as well. The hardware for the 5 TI... on the cards it is written what sort of card it is ie. "DC INPUT" or "230V AC OUTPUT", there is one output card that has the following written on it "TTL LAMP DRIVER" ? Is this card +5V for driving Transistor Transistor Logic ? It confused me because the backplane is fed with 24 VDC so, if this is TTL, the card itself must make it's own +5V ?

Can anyone shed any light on this?

Cheers

 

[AndyT]

Johnny T,
That is exactly what that module is for. It operates inside of the 0-5 VDC range. I do not remember if it requires a external 5VDC or the voltage is generated internal to the module. Also onthe 50/60 Hz timer issue the 5TI-103 has a dipswitch on the memory board to select the correct frequency which keeps the timers somewhat accurate.

I thought that road down memory lane had been closed a long time ago.

Andy

 

[Johnny T]

AndyT

Thanks for the prompt reply mate.

Another question which has arisen as I've been translating the code is this...

I have found an output and input that are way outside the range of the 5TI's hardware. The outputs go up to Y43 but in the software there is a rung that has a coil labelled Y117 !!

Similarly, the inputs go up to X67 but in the software listing there is an X100.

I just wondered if this was just an old style of using a dummy contact that will never be used, or if there is something I'm missing.

Has anyone any ideas ?

 

[AndyT]

Johnny T,

Is this system using all 6MT I/O or by some chance is there TI405 I/O in the system also?

Andy

 

[Johnny T]

I'm not 100% sure Andy.

Some of the input units have 6MT13-D05L written on them.
Some of the output units have 6MT12-40BL written on them.

A lot of the others don't have anything on them. I can post a pic if it would help?

Thanks

John

 

[Johnny T]

Update...

All of the input units have 6MT13-D05L written on them, but some have it written slightly differently.

There are some of the output units that are blank though (apart from the four leds etc)

 

[AndyT]

Sorry Johnny, I was off base on that one. Facts Eng. built a 6MT to TI405 converter, I was thinking it was the other way. In that case the I/O numbering would have been in octal and could explain the difference in numbering.

Andy

 

[Jay Anthony]

There were some third parties that made both 5MT and 6MT modules. That maybe where your blank ones are coming from. Might check the side of the module.

If you've got one, post the pic. Might be an education for some of our younger members.

 

[Johnny T]

I've attached a pic of the beast...

Any ideas on the X100 / Y117 thing?

The X100 has been used about four times so far in the listing.

My initial thought was dummy marker but I can't understand why there would be a Y117 ?

 

[Ken M]

Sorry for the long gap in posting - my cycle time only just caught up!

The 'image register' in a 5TI was completely accessible by the program whether there was physical I/O attached or not. The I/O addressing was strictly additive - as you put in another input card or output card, another 4 points would now have real I/O related to them.

Writing to Y117 would be perfectly permissible. If there was no physical output at that address then a bit was set in the image register and nothing further happened. You could treat it as just another non-retentive CR. The potential problem was that if someone had done that, and extra I/O was then added which did now use that address - well, look out the man with his fingers in the clamp!

The other alternative is that X100 / Y117 did previously relate to real I/O which was subsequently removed, but the logic was never modified. It may just be a vestige of previous code.

Hey, and how come no-one has mentioned the predecessor of the 6MT I/O family, the 5MT? One point per module! Still, it meant that you didn't need a jeweller's screwdriver to connect up the wiring like some of these high-density cards today.

Regards

Ken.