The Sequel - Oh Blimey I bought a CNC Lathe (Beaver TC 20)

[cnc-it]

Yes I haven't gone that deep into pp editing..I know just enough to alter a standard post for 3 or 4 axis.

[awemawson]

These may help

[cnc-it]

Great..I hadn't realized these manuals were out there..now I can learn properly and not by my usual method of trial and error 

[PekkaNF]

Siemens Simatic S5 PG 675

Pekka that's EXACTLY the device with Step5 software that I need to read my Symatic 820T PLC ladder

We had least 20 extra PG675/685 in the storage, probably few left after premises were downsized. Engineers still have access to S5 with modern laptops (serial to current-loop adapter + programming program). That program is proverbial to install and update.

Old PG.s were pretty much bulletproof. Only problem was that cooling fan was not good enenough on some models and if you were in hot environment, the filter had to be removed or PG would die. Removing the filter has it's own set of complications - you don't want the PG to sit on dirty floor.

There was a luggable PG, used it anly a little time, never needed to touch the OS or S5 programming program. When we swiched to laptops there were more to worry about, starting from the physical connection (RS-232 to curren-tloop converter) and Siemens changing "sopy protect bit" and such too often and needed a certified excorcist to banish gremlings out of systems I lost interest and stopped working on them. Although S5 did beat the contemporary A-B, Telemecanique, AEG and ABB systems if you had over 2000 discrete I/O:s and some high speed counter/analog controls. Even simple timer functions were pretty advanced compared to other system. FB:s were black magick even when you have source code if you had no idea what they were trying to accomplish.

System was that plentiful, that I would imagine they are available e-bay.

Pekka

[awemawson]

Pekka,

I reckon it's time that you came over for a Holiday in the UK, I'm sure we can find a slot in the calendar for our holiday cottages. Borrow a colleagues STEP5 laptop and come and have a play

Objective: get a hard copy of the PLC ladder
Bonus: a free holiday for you and yours

A true win win solution   

https://www.cottages.com/cottages/lower-marley-farm-apple-cottage-27442

https://www.cottages.com/cottages/lower-marley-farm-quince-cottage-27443

[PekkaNF]

Nowadays I am next to useless on S5/S7 et.al. I should send a colleque. She is younger, smarter and she has S5 on laptop, but she has two teens, another is a rally driver and another is pricess....should be a lot of fun.

Pekka

[awemawson]

At least you have done it in the past, I've never even seen it running 

Looking on eBay you are right there are several on offer, but I'm not sure what I'm looking at as not a German speaker. The extra programmer unit is also available. I don't mind buying one so long as I don't choose the wrong thing in my ignorance. Any tips appreciated.

Were they all CP/M 86 based. I cut my teeth on CP/M with home brew Z80 / S100 systems and 8" floppy drives 

An alternative is somehow to get STEP5 on a laptop. I revived a Toughbook running XP only yesterday to see if it's battery was any good, as it has a proper serial port.

But all my attempts so far to source a working and enabled STEP5 have come to nothing, all very frustrating.

[PekkaNF]

I used program and start machines, mostly with S5/S7 and mostly in ladder. But that was long time ago and there was always someone to call, beacuse there were leasto of 20 of us at any given time. Therefore my knowledge is very limited and spesific. But I could ask some pointers from the new blood.

You are right, the old ones were CP/M, but OS was used mainly to copy discs, BU-files and very basic stuff. Everything to do with Siemes was on that all encopasing programing program. Maybe here is one obsolote, but operational unit floating somewhere. Have to ask, hopefully my mailbox is not litterd with URGENT-messages on Monday - I might even remember it until lunch:)

Pekka

[awemawson]

Pekka that would be very kind.   


Presumably with the right software PG 675 / 685 / 720 or 740 would work ?

[David Jupp]

Where I used to work we had S5 PLCs controlling some plastic compounding equipment.


Our process control guy had a luggable Siemens PC (yes I mean an IBM PS2 compatible) to talk to the PLC- I don't remember clearly, but i suspect it was DOS based (1990s).  3.5" floppy drive.

[PekkaNF]

Uhh. it is actually now bigger problem than it used to be. I asked the SW engineers and they all said that it is nearly impossible to get any of the S5 application program running on modern/latest laptop.

1: First problem is the physical: The current loop dongle works only with real RS-232 serial port, docking stations do not support it. There is a rumour that one USB-dongle worked with it, but newer models don't. Even when they state they do.

2: Windows version. S5 aplication programs are very old. Basically if you need to program EEproms (or even Eproms) for cumminacion cards etc. it's nearly no-go. They have one ancient PC from someone's home that runs with all those programs. There were some laptops that run the old programs and were used, but I.T. tries to hunt them down and confiscate (security risk, old operating system, danger of connecting them into internal network......). Situation has got worse from 2013 after big downsizing/move.

Do you have the cables and serial to current-loop converter + all  the cables?

I'm going to ask someone I'll meet later this week what are they useing to connect obsolote S5, I know we have the projects and least some of them would benefit greatly if there were a way to connect to live PLC and see what is actually running and what I/O is being adressed (after 20 years of use and countless rebuilds mills tend to add some aux controlls to closest available PLC and much joy if the sump pump or extreaction fan is disconnected permanently).

I am sorry about the bad news. I wish I had stached some of the stuff they trashed 5 years ago.

Pekka

[awemawson]

Pekka, I have a working Panasonic Toughbook CF-50 running XP with a real RS232 port - in fact I loaded OPERA browser on it only this morning as  Chrome, Firefox etc no longer support XP

What i don't have is the software, the dongle, or the cable. No doubt the RS232 to current loop can be sorted relatively easily.

As an alternative I am watching this on eBay :

https://www.ebay.co.uk/itm/Siemens-6ES5675-0UA11-Simatic-S5-PG675-Programmierger%C3%A4t/113100786538?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

But I'm not sure if those two floppies represent all the software that is needed.

Also I am following this programmer, which I think is the correct one:

https://www.ebay.co.uk/itm/Siemens-6ES5985-2AA11-MEP-Module-Eprom-Programmer-for-PG-675-E-Stand-2/391926287016?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649


BTW thanks for remembering 

[PekkaNF]

For serial communication, we needed
1: Cable from PC RR-232 to converter
2: Wall wart for converter and converter
3: Cable from converter to PLC, there were least two types one D15 and one D25

Something like these:
https://www.ibhsoftec.com/epages/63444704.sf/en_GB/?ObjectPath=/Shops/63444704/Products/2042

I remember working with U115, U135, and U155 CPUs. Sometimes we had to solder the cables, when they got lost, broken or worn. I think the currentloop converter was internaly fairly simple affair like two optocouplers, resistors to set the current and constant current source. Something like this:


*bit more google, I don't rememenber seeing these, but I could be the right thing*
https://www.ebay.co.uk/itm/New-6ES5-734-1BD20-Programming-Cable-For-PC-TTY-PCTTY-Siemens-S5-PLC-/141723080984


I am not sure if the floppies are reliable after all these years, least I can't open the files from the floppies I had from that time. Still more reliable than 3.5".

This is how the boot looks like:

PG 685 would have a HD and all programs on that one. Darn. Now when I think of it, I have forgot most of it. There some other like PG 740/750.

You really have a knack of finding a challenge.

Pekka

[awemawson]

I spent some more time today trying to investigate why I can't get the Renishaw optically coupled probing system working.

It consists of four elements:

An MI12 'Machine Interface' - (A box that talks to the Siemens control and the OMM )

An OMM (Optical Module Machine - machine mounted infra red sender receiver )

An LT02 (Tool Turret mounted infra red sender receiver)

An LP2 that mounts on the LT02 (a sensitive switch operated by a probe touch)

What is supposed to happen, is that the MI12 tells the OMM to 'wake up' the LT02 as it has an internal battery that needs preserving. Once awake, if the ruby probe tip trips the LP2 switch element, the LT02 transmits a signal to the OMM,  which passes it to the MI12, which gives a signal to the Siemens controller that we are in contact.

[awemawson]

Now from previous work I had proved that the OMM is transmitting an IR 'wake up' signal, comprising a 250 millisecond burst of 125 uSec period pulses every second. I did this by cobbling together my own IR receiver.

Now there was no apparent response from an LT02 held in range and triggered. So maybe the LT02 is faulty, or maybe the OMM is not receiving ?

So today's task was to dismount the OMM and have a look at it's electronics and see if I could glean any further information. Not the easiest thing to get at, being behind the machine sliding door, but just possible.

The wires are pretty delicate and extremely short making the job an utter joy !

First the outside glass cover has to come off, and a shroud, giving access to the wiring terminals. To get a bit more space to move, I took the OMM off it's mounting bracket.

[awemawson]

So the next job was to remove the electronics and power them up on the bench. The MI12 supplies 10 volts to the OMM so that's what I gave it. To my surprise although the power LED came on, the Yellow 'wake up' LED didn't. (it had in the machine) Investigating further showed me that the 1 second / 250 millisecond / 125 microsecond bursts were actually formed in the MI12 - the OMM just passes them on as IR - (this fact becomes relevant later)

Now what I wanted to do was prove that the IR receiver part of the OMM was (or was not) working. Using a remote control from an LED Floodlight, I clamped one button 'pressed' , arranged it to point at the OMM IR sensor, and poked about in the circuitry with my 'scope probe. Now much of the electronics near the IR sensor is covered by screening cans that are not easy to remove, and it's all a bit tiny being surface mount. However I did find responses to the IR signals that I was sending, so the IR diode must be working.

I then went to the other end of the electronics, where a DS8921M differential line driver talks to the MI12 - no output, and also no input. Now between where I found the response, and this chip, there is more hidden circuitry that I can't get at. But  I don't think that there is anything sophisticated enough to be decoding signals, just buffering and level shifting. This is where the relevance of that wake up signal comes in. If the designer put the clever bit of the wake up signal back in the MI12 unit, he probably did the same for the touch received signal (maybe !!!!)

On the board are two miniature LM7805 5 volt regulators (that are working) and an ICL7660 switching voltage converter that is producing a -3.5 volt negative rail, but I have no idea if this the the 'right' voltage of course.

So in conclusion, it's inconclusive  The IR diode is working but I still don't know if the OMM or the LT02 is the actual fault !

Really I need to find another machine equipped with this system and wave my LT02 at it's OMM!!

In the end I put it all back together and took the dogs for a walk !

[PK]

The ICL7660 is a switched capacitor circuit, it's commonly used to produce a negative rail for op amps. The output voltage should be a negative mirror of the input voltage, so measure pin 8 vs pin 5 (with pin 3 as your reference) the voltage on 5 should be the negative equivalent of pin 8.... If it's not then you have a cap or over current problem.

PK

[awemawson]

Thanks for that PK.

Your response has prompted me to look very closely at the photos I took at the time.

I've spotted what looks to me to be an exploded surface mount capacitor - if it's the same as others on the board it should be 33uF at 16 volts - certainly  doesn't look healthy

Of course it's all back together now 

[PK]

Yeah, that looks like the bulk cap for the input to the 7805, look for ripple on the little output ceramic in that picture.
Anything more than a few hundred mV is bad.

[cnc-it]

Looks promising..if that capacitor is blown chances are it's something on the circuit that has gone out of spec and blown the capacitor rather than it failing all by its self.

[PK]

IMO, input caps for regulators tend to blow when they see voltage spikes, so I wouldn't be too concerned about root cause..... Just replace it and trust in Jesus......
PK

[awemawson]

I've got an SMD capacitor on order, and I won't pull the OMM again until it's to hand. But if it is the input cap for the 5 volt regulators then I doubt that it's the fault, just 'a fault' as both 5 volts regs measured ok on the Fluke - this thing takes in 10 volts from the MI12 which is itself regulated (I'd assume) so as PK says - just change it !

The cabling for this device is ridiculous. The MI12 sits in the hydraulic cupboard under the controller where there is a 24 volt supply, but the MI12 takes it's 24 volts from a cabinet at the diagonally opposite (rear) corner, with the cable draping all over the place and passing through ungrometed holes. The MI12 to OMM cable goes round three sides of the machine to join front right to front left, with the same draping cables. When it's working (if?) there will be a re-routing exercise.

It was obviously an 'upgrade on site' and of course although I have all the panels off at the moment, the chap who installed this didn't, so it's easy to be critical unjustly. 

[awemawson]

The ordered SMD capacitor arrived by post this morning, so I braced myself for some VERY tiny soldering. But when I opened the envelope I thought - 'by heck those ARE small'

So rather than dis-mount the OMM and find that I'd cocked up the order I thought I'd try and scale the size from the photographs knowing the size of an 8 pin SOIC IC (which was in the same frame)

Turns out these 33 uF caps need to be between 6.7 and 8.5 mm long, whereas the ones I ordered are only 4 mm long 

Never mind, better to find out now rather than when the thing is in bits on the desk stopping everything else while waiting for parts. So another order sent off, and this time (plonker before didn't!) I checked the physical size - 7.3 mm long in this case - should arrive tomorrow

. . . hey ho . . onwards and upwards

[PK]

If the voltage rating is adequate, then just solder them in. 7805's aren't particular about input  caps.

[awemawson]

PK at that scale I don't fancy putting in wire extensions - it's about the limit of my soldering dexterity to get them off and on, never mind extra floating bits of wire 

(Although I do have a hot blower as part of my de-soldering iron I suspect I'll just use a very fine tip for this capacitor)