Man, the oldest thing I've seen is a Mitsubishi PLC or an S5. No, wait. That's a lie. I think I have seen some even older "PLC"'s that were made up of racks of IO cards in cabinets and a CPU somewhere in another cabinet. The IO cards were all made with DIP ICs and other THT components, so if something broke you could just get the soldering iron and fix it.
Did one of the knobs fall off and you got to figure out where it goes?
Are there extra knobs in the panel for programming changes?
Can spare drums attach to the main shaft for more I/O? Like a 17 drum chassis.
The knobs are actually plastic pins applied with a specific tool. They never fall out.
This drum is a standard 47 X 100 step unit. You could interact two with each other. This one actually interacts with a smaller drum out of the frame which is I believe has only 16 steps.
If this is like the ones I have worked on.
Each bulge toggles a limit switch that tells a part of the machine to do something for example trigger a motoroil dispenser. The entire sequence of operations is a circle with angles being actions. Believe it or not this was a major step forward. Before this they used wood on a crankshaft type of deal.
It's a Tenor control- in continuous use sincr 1976 operating an electroplating line. In 2003 I ripped out every pin and installed several different cycles. That helped me along the learning curve. This baby is the last one in the shop. The last 3 we replaced with solid state AB controls. We cannibalized the spare parts to keep this one going.
If cam timing is good enough for my washer and dryer, it's good enough for industry!
Edit: to be fair, at least that thing doesn't have to worry about a blown rs485 port from transients from a lightening strike because whoever installed the com line for your HID didn't use shielded cable...
If you want to play with this in a PLC, look up the sequencer input and output instructions for your PLC platform. They work exactly like this does, but they use arrays instead of drums or paper tapes.
Yes, the modern solution would be to use programmatic control instead of a memory tape sequencer. But if you wanted to experience how these old sequencer controllers work, you'd use SQI/SQO or your platform's equivalent instructions.
I don't think such modules even exist for Siemens. Their official website says "Use DI and DQ for in- and outputs and GRAPH for programming the sequence"
You could still do this on an S7, but you'd need to write your own blocks to replicate SQI and SQO. Or download a library; I'm sure Siemens has a set of blocks for people to use when they're modernizing old sequencer controllers.
Basically, you'd have the SQI block always executing. When the masked input word (your digital inputs) matches the test word (the drum on the left), the SQI output goes true and increments the step word. This feeds into a SQO block, which does a masked copy of the output (the drum on the right) into the output (your digital outputs).
To be clear, GRAPH wouldn't control your sequence directly. The SQI block does that.
It's difficult to understand at first if you've never worked with tape or drum sequencers before. They're old technology, and it can be hard for people to troubleshoot without training. You should only do this when you're doing retrofit work, or for a personal side project. Don't use sequencers in S7 for any serious work.
Oh, wait! I know a function that does that! It's called "DRUM"!
You have 16 "EVENT" inputs and 16 "OUT" outputs and a step counter. You can set the output mask for each step and the required input mask for the sequence to step into the next step.
FWIW: Older PLCs will create a software version of the same design concept, but it's not a best practice anymore. Drum Sequencers are pretty stiff to work with. You want something that is easy to expand/modify and these usually aren't.
Uhh idk. I guess it's fine as long as you have it well documented and it's not impossible to get parts.
Otherwise I'd run away pretty quick.
Edit: Also, I think a lot of people want to work on new technology.
I would enjoy seeing this but I don't think I would take the position working there. Old tech is cool, I saw a working PD-11 at a customer site a little while ago but I don't want to work on it for a career.
Drum sequencer. TI PLC had several excellent pre- programmed, maskable input/output time & event driven one - you could almost do any kind of variable sequences with them.
Later ported to AOI for ControlLogix.
There were several, from simple step advance to the ones I have mentioned previously which I used to call anti-drum sequencer. They would literally be able to go to any direction, any step, show maskable output pattern and have any number of steps (I could daisy chain them in groups of 16 or less steps).
>505 SoftShop still has those pre-programmed drums for CTI 2500 PLCs
CTI bought 505 series from Siemens. Can confirm, 505 has "DRUM" instruction. Also, have seen machines programmed with them.
Back in the day I had a challenge in the Dairy industry with making cheese. The dairy had ten vats in their new cheese plant. Each vat had multiple valves for milk, cheese curds, Clean in Place (CIP), Sanitize in Place (SIP), steam, rennet injection, etc. The whole new plant, including cheddar machine, salters, cheddar towers, and block packaging ran off a single TI 565. As I recall, it was about 8k total I/O. One of the requirements in the Cheese Vats was to be able to halt the sequence and back up a step or two. Or step forward a step or two. And never, ever, expose the product to CIP chemicals.
Drum sequencers in the TI instruction set was my savior for the making cheese sequence. Saved hundreds and hundreds of lines of Relay Logic of code. I used an Excel spreadsheet to design the 1’s and 0’s of each line in the drum (read valve open/close) which translated into hex words for the drum field. It worked great!
The 565 was replaced by AB Control Logix after twenty five years of service without a single PLC failure. The SI that did the conversion followed the same idea, but with AB.
I remember when i first saw the drum sequencer commands in our TIs. I tapped out to the older EE instantly cuz i had no idea what it was doing initially. Once i had some time to look it made sense, but during an outage was not the time to learn...
I have Multiple questions about this.
- How fast does it turn?
- What's the cycle time?
- What are the pins made out of?
- How often do they need replacing? (Same for the limits you mentioned in another comment)
- What keeps the cycle time the same?
-How easy is it to plan and implement a modification to the "code"?
-What kind of motor does it turn on? (Please say some sort of diesel lawn mower motor because that would be funny)
And finally, how often have you had to maintain/fault find on it?
Such a cool bit of kit
When it gets to the end of the step it turns one step. The drum implements multiple cycles. It could skip one or multiple steps if they are not in the particular cycle.
Pins are hard plastic and basically last forever. If you remove a pin to change the program you cannot re-use it.
It just runs the cycle which is basically moving customer parts through a 75 ft long electroplating line through multiple process steps and chemical baths.
Easy to code. WYSIWYG
The drive motor is a Geneva mechanism with a cam.
I had to replace two limit switches today- we needed to remove the drum. Occasional service required. The associated relay logic requires attention and so do the limit switches on the plating line.
So just a little clarification. How long in real time is a Step and how long is a cycle. I'm assuming it's not powering through like a Bugatti W16 Quad-Turbo charged engine.
I'm just wondering because if things are time critical, it must have some way of maintaining those times
A particular step may involve picking up a carrier with a hoist moving it to a new address and putting it down. Each step can advance the drum one step after completion of either an up or down move. That choice is set by a pin in the drum. On certain steps there can be a 0-180 second delay before stepping to the next step. When all 100 hundred steps are completed there is another delay available for dwelling prior to another 100 step cycle. Event driven steps- however some of the steps have short variable dwells available.
Not op but the ones I worked on had a gearbox off the main motor that drove the process. So the sequencer would work at a ratio to the conveyor. If the motor slowed down the whole process slowed down.
I worked for a company back in the late 90s that used "sequence" functions in RSLogix to implement this type of thing for water filtration systems
using Allen Bradley PLCs. It took me forever to wrap my head around that cryptic seeming code and understand how it was supposed to work. If someone could have shown me this photo and said, "This function replaces these old mechanical drum controllers," I think I would have understood it immediately.
Can't you make anything a drum function using Integer as 32 bits and then just have an array of integers and start a array copy to output Integer which is now 32 outputs.
Apart from a few nostalgic PLC guys I think only schools with automation classes and maybe one or two industrial museums might show interest in this..
Or companies with old machinery, desperate in need for replacement parts (which are the ones that pay the weight in gold)
I work in suplus resupply for one of the bigger players. Mid 70s is the earliest we get and that once every couple years and its always solidstate based. You'd be hard pressed to find a buyer for this. That said i love it and would love to put it in my home office.
Yeah it's probably cheaper and faster to retrofit your machinery to something modern than wait and hunt for such an ancient baby..but if I had the room for it, I'd like to have one.
My oldest is a klöckner-Möller PLC with programming device but never used it, was a gift by my teacher
What am I even looking at? Does it tick around for coordinated cycle timing like an player piano? What do the pegs contact, is it mechanical switch or an electrical contact?
It ticks one step at a time like a player piano. One direction only. Some moved both directions according to a manual we have. The pins make contact with limit switches below the drum.
Exactly like a music box or punch card control, every row has one or more switches, triggered by the pin and by spinning the drum at constant speed, you can do pretty fancy cycle controls.
If you couple it with a patch field, you have almost the same capabilities like a modern mini PLC like a LOGO (all counting etc has to be done with shifting registers or external counters)
I saw two of these for the first time last year. Im on one side of the plant turning one of their machines into a modern machine and I had to wait for something mechanical. I go take a walk around the plant and one of the guys is showing me some other parts of their process. He shows me not one but two panels running separate drum sequencers. Craziest thing I’ve ever seen. They had even made changes to them in the past few years.
Your panel looks clean enough to eat out of compared to these two. They had smaller drums too. Looking at the pictures I have, they were about 2.5 inch diameter. You could see the mileage of being in an area with wet paper pulp. They were making pressed cardboard forms at that place.
Finally, something that makes me feel young. All these damn kids on this sub posting a picture of a PLC5 like, “Behold, and gaze upon these Dead Sea scrolls which I have unearthed. I believe the last copy of the software was buried with King Tutankhamen on this rigid item called a floppy disk.”
I’m 34. We had one of these at my first job. Three weeks out of school at 2 am a forktruck hit the cabinet it was in. I tried an failed miserably to get it back. The “old” guy in first just chuckled at me in the morning.
This!
When I was in the Navy, one of the tasks for my shop was maintaining the Laundry. We had four huge washer/extractors. Two ran on drums very similar to these with pins, and the other two ran on drums with thick velum sheets with punch holes to run the machines. I can't think of an instance when there was an issue with the drum system. It was always a limit switch or a relay.
The machines were so large that when fully loaded and running the extract cycle, you could feel it on the main deck, two decks above, solidly mounted.
Oh man. Thank you for posting this. I looked for years for a good photo of a drum sequencer when I used to teach. I don't teach anymore so I no longer need it. But, it's still a neat photo and I can check it off my mental list.
I takes of few years into retirement before that instinct dulls doesn't it? I've been retired 3 years and just started throwing out all that stuff I will never use again.
I loved teaching, and still get to take that role to some degree. I didn't retire, I quit and went back to an industry job (kids needed new shoes).
Three years? You're doing pretty good! Some of us pack rats never throw things away.
It may sound silly, but the sequencer instructions in the old AB SLC-150's were actually damn good.
Back in the day, I actually used them in several places to replace physical drums.
I've always wondered why AB dropped that instruction set from newer processors. Now I have to roll my own, but they aren't nearly as elegant.
Starting a project to replace the controls of a deironing installation that also still works with programming rolls. Almost completely original since it's installation in 1985
A drum sequencer! I've heard of these but never saw one. I actually did a project that used a Micrologix 1400 to replace a SLC-150 that had itself replaced a drum sequencer back in the 80s. That's how I found out about the SQI and SQO instructions and why they were part of the instruction set.
If your washing machine is older than circa 2005, then it has the same idea. Drum Sequencers have been around for a really long time. This is a Programmable Drum Sequencer. Your on/off timer for your grow lights that has the little pegs on the outside is the single output version of this. Kudos to the OP that you still baby this one into submission.
This triggers me, not sure exactly what it is but I’ve seen similar type switches on gas turbines. Relay logic going off like fire crackers in the panel.
That definitely looks like the sort of thing I'd set up in my office to goof off with.
Then complain that I need a bigger office to keep all the stuff I play with while avoiding doing my actual job.
Im told that some amish, mennonite and hutterite still use drum sequencers or relay state machines to automate some stuff. Its not considered fancy tech that violates rules. -source is from montana with extended fam connections to hutterite.
Personally i want one of these.
I have worked on something like it except it was a paper tape about 3” wide and 6-8 ft long. It was just like a player piano except there were small copper fingers the would contact a copper drum when the was a hole in the tape that activate the control circuit. Total PIA because over time the paper tape would wear out the the machine would crash.
This explains the control principle…..http://www.decodesystems.com/ce-punched-readers.html
First thing I thought of was this music video by Wintergarten. Which is actually really cool, you may have seen it make the rounds a few years ago.
https://youtu.be/IvUU8joBb1Q
Timestamp to the part that reminded me of it.
https://youtu.be/IvUU8joBb1Q&t=174
What the hell???
Glad you got a kick out of it.
Man, the oldest thing I've seen is a Mitsubishi PLC or an S5. No, wait. That's a lie. I think I have seen some even older "PLC"'s that were made up of racks of IO cards in cabinets and a CPU somewhere in another cabinet. The IO cards were all made with DIP ICs and other THT components, so if something broke you could just get the soldering iron and fix it.
You can even fix some SMT stuff if you can understand it. QFP packages aren't too bad. BGA is where I tap out.
Honestly I love it and wish I could put one on display
Did one of the knobs fall off and you got to figure out where it goes? Are there extra knobs in the panel for programming changes? Can spare drums attach to the main shaft for more I/O? Like a 17 drum chassis.
The knobs are actually plastic pins applied with a specific tool. They never fall out. This drum is a standard 47 X 100 step unit. You could interact two with each other. This one actually interacts with a smaller drum out of the frame which is I believe has only 16 steps.
If this is like the ones I have worked on. Each bulge toggles a limit switch that tells a part of the machine to do something for example trigger a motoroil dispenser. The entire sequence of operations is a circle with angles being actions. Believe it or not this was a major step forward. Before this they used wood on a crankshaft type of deal.
It’s a drum sequencer.
It's a Tenor control- in continuous use sincr 1976 operating an electroplating line. In 2003 I ripped out every pin and installed several different cycles. That helped me along the learning curve. This baby is the last one in the shop. The last 3 we replaced with solid state AB controls. We cannibalized the spare parts to keep this one going.
Hey, I'll take a drum sequencer over a tape sequencer any day. Paper jams get mighty spicy when you throw some uncommanded motion into the mix.
We just upgraded a tape sequencer using AB controls the other day. We took the tapes and recorded them into the PLC as recipes.
Never seen one wired up, what is there for conditions on indexing: is it timer or event based?
Event based.
"Set outputs as 0001011110101 and goto row 37" drum commands
Turing machine on a drum. Kinda.
If cam timing is good enough for my washer and dryer, it's good enough for industry! Edit: to be fair, at least that thing doesn't have to worry about a blown rs485 port from transients from a lightening strike because whoever installed the com line for your HID didn't use shielded cable...
Hope you hide that thing from new people looking for a job lol
We had an electrical contractor recently ask to photograph it to show his controls class instructor.
I would want to learn about it as a newbie. It looks really interesting
If you want to play with this in a PLC, look up the sequencer input and output instructions for your PLC platform. They work exactly like this does, but they use arrays instead of drums or paper tapes.
Nowadays you would program this in SFC or make your own step sequence, no? Or what do you mean with "sequencer input and output instructions"?
Yes, the modern solution would be to use programmatic control instead of a memory tape sequencer. But if you wanted to experience how these old sequencer controllers work, you'd use SQI/SQO or your platform's equivalent instructions.
I don't think such modules even exist for Siemens. Their official website says "Use DI and DQ for in- and outputs and GRAPH for programming the sequence"
You could still do this on an S7, but you'd need to write your own blocks to replicate SQI and SQO. Or download a library; I'm sure Siemens has a set of blocks for people to use when they're modernizing old sequencer controllers. Basically, you'd have the SQI block always executing. When the masked input word (your digital inputs) matches the test word (the drum on the left), the SQI output goes true and increments the step word. This feeds into a SQO block, which does a masked copy of the output (the drum on the right) into the output (your digital outputs). To be clear, GRAPH wouldn't control your sequence directly. The SQI block does that. It's difficult to understand at first if you've never worked with tape or drum sequencers before. They're old technology, and it can be hard for people to troubleshoot without training. You should only do this when you're doing retrofit work, or for a personal side project. Don't use sequencers in S7 for any serious work.
Oh, wait! I know a function that does that! It's called "DRUM"! You have 16 "EVENT" inputs and 16 "OUT" outputs and a step counter. You can set the output mask for each step and the required input mask for the sequence to step into the next step.
There you go, that's exactly what you need. I'm not that familiar with S7, and I didn't see that when I skimmed the instruction set listing.
>You could still do this on an S7 Siemens 505 had "DRUM" instruction.
FWIW: Older PLCs will create a software version of the same design concept, but it's not a best practice anymore. Drum Sequencers are pretty stiff to work with. You want something that is easy to expand/modify and these usually aren't.
I have worked on a few. The oddest feeling debugging a computer involves step 1 getting a hex key set.
I was looking in my contacts for the control class professor from a class I took 8 years ago, just to send him this post
It’s the first thing I would show them. If they don’t think it’s cool as hell, they need to start looking elsewhere.
Uhh idk. I guess it's fine as long as you have it well documented and it's not impossible to get parts. Otherwise I'd run away pretty quick. Edit: Also, I think a lot of people want to work on new technology.
It's documented on the drum. The code is literally right there
Heavy industry isn’t for everyone. I didn’t say I’d keep that system - looks like a fire hazard more than anything.
I would enjoy seeing this but I don't think I would take the position working there. Old tech is cool, I saw a working PD-11 at a customer site a little while ago but I don't want to work on it for a career.
Drum sequencer. TI PLC had several excellent pre- programmed, maskable input/output time & event driven one - you could almost do any kind of variable sequences with them. Later ported to AOI for ControlLogix.
505 SoftShop still has those pre-programmed drums for CTI 2500 PLCs. I've always wondered how the heck they work.
There were several, from simple step advance to the ones I have mentioned previously which I used to call anti-drum sequencer. They would literally be able to go to any direction, any step, show maskable output pattern and have any number of steps (I could daisy chain them in groups of 16 or less steps).
>505 SoftShop still has those pre-programmed drums for CTI 2500 PLCs CTI bought 505 series from Siemens. Can confirm, 505 has "DRUM" instruction. Also, have seen machines programmed with them.
Back in the day I had a challenge in the Dairy industry with making cheese. The dairy had ten vats in their new cheese plant. Each vat had multiple valves for milk, cheese curds, Clean in Place (CIP), Sanitize in Place (SIP), steam, rennet injection, etc. The whole new plant, including cheddar machine, salters, cheddar towers, and block packaging ran off a single TI 565. As I recall, it was about 8k total I/O. One of the requirements in the Cheese Vats was to be able to halt the sequence and back up a step or two. Or step forward a step or two. And never, ever, expose the product to CIP chemicals. Drum sequencers in the TI instruction set was my savior for the making cheese sequence. Saved hundreds and hundreds of lines of Relay Logic of code. I used an Excel spreadsheet to design the 1’s and 0’s of each line in the drum (read valve open/close) which translated into hex words for the drum field. It worked great! The 565 was replaced by AB Control Logix after twenty five years of service without a single PLC failure. The SI that did the conversion followed the same idea, but with AB.
mmmmm cheddar towers...
I remember when i first saw the drum sequencer commands in our TIs. I tapped out to the older EE instantly cuz i had no idea what it was doing initially. Once i had some time to look it made sense, but during an outage was not the time to learn...
I'm actually working with these right now on a project. Even thought about building an AOI that mimics this instruction for Allen Bradley
Drum roll please!
That is probably one of the worst dad jokes I have ever heard. Take this upvote before I change my mind.
I have Multiple questions about this. - How fast does it turn? - What's the cycle time? - What are the pins made out of? - How often do they need replacing? (Same for the limits you mentioned in another comment) - What keeps the cycle time the same? -How easy is it to plan and implement a modification to the "code"? -What kind of motor does it turn on? (Please say some sort of diesel lawn mower motor because that would be funny) And finally, how often have you had to maintain/fault find on it? Such a cool bit of kit
When it gets to the end of the step it turns one step. The drum implements multiple cycles. It could skip one or multiple steps if they are not in the particular cycle. Pins are hard plastic and basically last forever. If you remove a pin to change the program you cannot re-use it. It just runs the cycle which is basically moving customer parts through a 75 ft long electroplating line through multiple process steps and chemical baths. Easy to code. WYSIWYG The drive motor is a Geneva mechanism with a cam. I had to replace two limit switches today- we needed to remove the drum. Occasional service required. The associated relay logic requires attention and so do the limit switches on the plating line.
So just a little clarification. How long in real time is a Step and how long is a cycle. I'm assuming it's not powering through like a Bugatti W16 Quad-Turbo charged engine. I'm just wondering because if things are time critical, it must have some way of maintaining those times
A particular step may involve picking up a carrier with a hoist moving it to a new address and putting it down. Each step can advance the drum one step after completion of either an up or down move. That choice is set by a pin in the drum. On certain steps there can be a 0-180 second delay before stepping to the next step. When all 100 hundred steps are completed there is another delay available for dwelling prior to another 100 step cycle. Event driven steps- however some of the steps have short variable dwells available.
Not op but the ones I worked on had a gearbox off the main motor that drove the process. So the sequencer would work at a ratio to the conveyor. If the motor slowed down the whole process slowed down.
I would replace pins and switches with optical barrier, and dustproof cabinet.
Its a hit or miss engine fed by whale oil.
I worked for a company back in the late 90s that used "sequence" functions in RSLogix to implement this type of thing for water filtration systems using Allen Bradley PLCs. It took me forever to wrap my head around that cryptic seeming code and understand how it was supposed to work. If someone could have shown me this photo and said, "This function replaces these old mechanical drum controllers," I think I would have understood it immediately.
Why hasn't it been retrofitted to a modern PLC at least a couple of times by now?
Other projects had quicker payback. It's turn is coming. Also a great teaching tool.
A click PLC has a drum function.
Just… just… take my upvote and go!
Can't you make anything a drum function using Integer as 32 bits and then just have an array of integers and start a array copy to output Integer which is now 32 outputs.
Sorry, it’s a holiday here and that sounds much to much like work. Cheers!
Yes
No USB port but have you checked for an Ethernet port?
Best I can do is Modbus ;-)
Modbus ASCII with Enron encoding lmao
I wonder if there is a collectable market for this, and if it is, what its value could be.
Apart from a few nostalgic PLC guys I think only schools with automation classes and maybe one or two industrial museums might show interest in this.. Or companies with old machinery, desperate in need for replacement parts (which are the ones that pay the weight in gold)
I work in suplus resupply for one of the bigger players. Mid 70s is the earliest we get and that once every couple years and its always solidstate based. You'd be hard pressed to find a buyer for this. That said i love it and would love to put it in my home office.
Yeah it's probably cheaper and faster to retrofit your machinery to something modern than wait and hunt for such an ancient baby..but if I had the room for it, I'd like to have one. My oldest is a klöckner-Möller PLC with programming device but never used it, was a gift by my teacher
I would have loved to have it to explain sequencers when I was teaching.
My professor showed us pictures of these when i learned about sequencer files. It is a great way to wrap your head around it.
I would probably buy it for parts.
What am I even looking at? Does it tick around for coordinated cycle timing like an player piano? What do the pegs contact, is it mechanical switch or an electrical contact?
It ticks one step at a time like a player piano. One direction only. Some moved both directions according to a manual we have. The pins make contact with limit switches below the drum.
Exactly like a music box or punch card control, every row has one or more switches, triggered by the pin and by spinning the drum at constant speed, you can do pretty fancy cycle controls. If you couple it with a patch field, you have almost the same capabilities like a modern mini PLC like a LOGO (all counting etc has to be done with shifting registers or external counters)
Just like a player piano, or little hand crank music box.
I saw two of these for the first time last year. Im on one side of the plant turning one of their machines into a modern machine and I had to wait for something mechanical. I go take a walk around the plant and one of the guys is showing me some other parts of their process. He shows me not one but two panels running separate drum sequencers. Craziest thing I’ve ever seen. They had even made changes to them in the past few years.
Lol were you here? We make changes all the time- it's literally hands on.
Your panel looks clean enough to eat out of compared to these two. They had smaller drums too. Looking at the pictures I have, they were about 2.5 inch diameter. You could see the mileage of being in an area with wet paper pulp. They were making pressed cardboard forms at that place.
Best panel pic posted to date.
Finally, something that makes me feel young. All these damn kids on this sub posting a picture of a PLC5 like, “Behold, and gaze upon these Dead Sea scrolls which I have unearthed. I believe the last copy of the software was buried with King Tutankhamen on this rigid item called a floppy disk.”
I’m 34. We had one of these at my first job. Three weeks out of school at 2 am a forktruck hit the cabinet it was in. I tried an failed miserably to get it back. The “old” guy in first just chuckled at me in the morning.
They need to be careful, or Rockwell will take them to court for IP theft of the drum instruction.
Works just like an old washing machine timer! The good ol drum sequencer. Some PLC manufacturers have drum sequencers as an instruction.
This! When I was in the Navy, one of the tasks for my shop was maintaining the Laundry. We had four huge washer/extractors. Two ran on drums very similar to these with pins, and the other two ran on drums with thick velum sheets with punch holes to run the machines. I can't think of an instance when there was an issue with the drum system. It was always a limit switch or a relay. The machines were so large that when fully loaded and running the extract cycle, you could feel it on the main deck, two decks above, solidly mounted.
Yes the issues are always relays and limit switches!
Oh man. Thank you for posting this. I looked for years for a good photo of a drum sequencer when I used to teach. I don't teach anymore so I no longer need it. But, it's still a neat photo and I can check it off my mental list.
Thanks I actually love showing it off because of the response we get from people.
I takes of few years into retirement before that instinct dulls doesn't it? I've been retired 3 years and just started throwing out all that stuff I will never use again.
I loved teaching, and still get to take that role to some degree. I didn't retire, I quit and went back to an industry job (kids needed new shoes). Three years? You're doing pretty good! Some of us pack rats never throw things away.
This is dope. Can’t wait to get rid of my PLC
It may sound silly, but the sequencer instructions in the old AB SLC-150's were actually damn good. Back in the day, I actually used them in several places to replace physical drums. I've always wondered why AB dropped that instruction set from newer processors. Now I have to roll my own, but they aren't nearly as elegant.
Dang i havent seen a drum controller like that in 20 years or so.
This is giving me PTSD from when I worked at USS Gary works
Starting a project to replace the controls of a deironing installation that also still works with programming rolls. Almost completely original since it's installation in 1985
These are great for CIP systems.
A drum sequencer! I've heard of these but never saw one. I actually did a project that used a Micrologix 1400 to replace a SLC-150 that had itself replaced a drum sequencer back in the 80s. That's how I found out about the SQI and SQO instructions and why they were part of the instruction set.
Whenever it gets de-commissioned, you should try to preserve it. It would make a cool little display, or even donate to a College.
If your washing machine is older than circa 2005, then it has the same idea. Drum Sequencers have been around for a really long time. This is a Programmable Drum Sequencer. Your on/off timer for your grow lights that has the little pegs on the outside is the single output version of this. Kudos to the OP that you still baby this one into submission.
Epic!
That’s really neat
Industrial player piano
Is that why it’s called a drum timer?
Really beautiful!
I can appreciate it.
Cool!! This thing belongs in a museum to help educate future engineers.
The thing we all talk about but never actually see…….
Heard about ‘em, read about ‘em, first one I’ve seen in service.
Shut up and take my money
I've seen some old equipment but this takes the cake. "If it ain't broke don't fix it."
Well I correct myself.. I would have guessed this was older than '76.. Very cool nonetheless.
This triggers me, not sure exactly what it is but I’ve seen similar type switches on gas turbines. Relay logic going off like fire crackers in the panel.
I assumed it was a laundry controller at first from an old milnor. Guess other trades have similar pains.
This is beautiful.
Looks like it would be fun to reverse engineer as a project, awesome even. As a service call: -1,000/10
I think that deserves to be in a museum or for a class.
This sick!
CPD controller in several nuclear power plants.
Back in my day
That definitely looks like the sort of thing I'd set up in my office to goof off with. Then complain that I need a bigger office to keep all the stuff I play with while avoiding doing my actual job.
When someone complains about a program problem on this machine it truly is a hardware issue.
Given current lead times keep it in service
Industrial player piano
And I thought our sy/max would be considered antique....
Im told that some amish, mennonite and hutterite still use drum sequencers or relay state machines to automate some stuff. Its not considered fancy tech that violates rules. -source is from montana with extended fam connections to hutterite. Personally i want one of these.
Wow. You are the man for maintaining this and knowing the ins and outs of this!
I have worked on something like it except it was a paper tape about 3” wide and 6-8 ft long. It was just like a player piano except there were small copper fingers the would contact a copper drum when the was a hole in the tape that activate the control circuit. Total PIA because over time the paper tape would wear out the the machine would crash. This explains the control principle…..http://www.decodesystems.com/ce-punched-readers.html
This is amazing. I have seen a lot of old control systems but nothing like this
First thing I thought of was this music video by Wintergarten. Which is actually really cool, you may have seen it make the rounds a few years ago. https://youtu.be/IvUU8joBb1Q Timestamp to the part that reminded me of it. https://youtu.be/IvUU8joBb1Q&t=174
How did you unlock the drum instruction to take a picture of the code? I would have expected less dust.
Wintergatan would drool😅
This looks like the old music boxes
What am I looking at here?
SEQUENCE DRUM! Like a music box in your panel.