Computer control Rollermatic or 1-18

[fltcoils]

If you could choose, which would be a better base unit for computer control, a 1-18 or a rollermatic?

Assuming one can redesign the pulleys to boost the spin speed of a 1-18, making that equivalent, is the overflowing rinse ability of the solid drum machines the way to go for really good wash/rinse?

 

[Unimatic1140]

Assuming one can redesign the pulleys to boost the spin speed of a 1-18,
You would also be increasing the agitation speed as well then which might not always be desirable. It would be much easier to research and implement changing the motor to a variable speed DC motor which would be controlled by the same computer (with a DC motor controller board installed in addition to the power relay board(s)). It's something I'm thinking about doing (long-term) to the Super Unimatic.

is the overflowing rinse ability of the solid drum machines the way to go for really good wash/rinse?
Yes and in my opinion the solid-basket overflowing filter system is by far the best of any filtering system.

 

[fltcoils]

Thanks Robert,

I like what you've done on the Super-Unimatic, that got me to this site some months ago.

That idea was based on running the motor at reduced speed for the agitation, to keep that correct, and only run full speed for the spin. But better yet..

I think I found a variable frequency drive for the AC motor. Control Resources sells one rated for 1hp, called the Stratus. See their pdf sheet. Even has a 9600/8N1 RS485 interface.

Now that might allow one to get whatever rotation speed one wishes, within some reason, without changing pulleys or anything. I like that. Get a Rollermatic or 1-18 to spin fast, and be able to get a very gentle agitation.

 

[fltcoils]

Here's a pic of the stratus.

I don't know the price but it certainly is more compact than a lot of the industrial VFDs.

 

[Unimatic1140]

That's very cool bill! One question, would you still need to change the motor to a faster rpm motor? Since the top motor speed in a Rollermatic washer is 1725rpm which translates to a top spin speed of 660rpm in a 1/18 Rollermatic. Does changing the frequency make the motor rotate above its rated speed at 60hz? Now if you changed the motor to a 3450rpm motor your top spin speed in the 1/18 would be 1320 rpm! Now that would be cool to see.

Something else to think about is this controller I found recently. I’m not sure but I think we can use this in other appliance applications instead of hooking up the machine to a whole PC computer. This seems to be a programmable relay that will allow you to use up to 8 possible components. The Super Unimatic has 12 components already so it wont work for that machine, but for less complicated "mosterization" of appliances this might work perfectly. There is a screen to allow you to select what ever cycle you have preprogrammed. You use a PC to design and transmit the cycle programs the relay box with the software that is included. I'm gonna check this out at some point when I tackle computerizing a vintage dishwasher someday.

http://www.factorymation.com/s.nl/it.A/id.44/.f?category=1297

 

[fltcoils]

That's the great part of course, you use the old motor! They run on the same motor, so something going 1800rpm given 0 torque load at 60 hz might go 3600 given 120 hz. The industrial web boards discussing VFDs suggest they can run a single phase motor 20% to 200% easily. Variable frequency is a LOT better than just triacs pulsing like a ceiling fan speed controller.

So just imagine, RS485 control of motor speed. 360 to 3600 RPM. But I don't know the torque load on your unimatic at full spin, or on a multimatic. Obviously it would be less than 3600 rpm given torque load.

I think DC motors came into vogue in the 80s because of analog systems, but with digital one can now go with AC. DC might still be cheaper for OEM mass production, but for tweakers perhaps a $150 for a controller isn't really that steep.

I'm sure the relay box would work like you say. I don't know about feedback for trip sensing ( water flow, temp etc), but the basic cycles, sure it would work. We just installed such a smart relay controller box for our lab.

 

[Unimatic1140]

Fabulous, maybe I wont need to rig up a DC motor inside a Un

Hey Bill, that is quite interesting. I didn't realize that there are AC motor controllers out there that can adjust the frequency of the power going to the motor and speed it up or slow it down. I LOVE THAT! So what I don't understand is how you would interface the Stratus board (that you pictured two posts above) with a PC. What is a "9600/8N1 RS485 interface"???

 

[jeff_adelphi]

Robert, I have been looking at those Teco controllers also, they have expansion modules also that can be attached if you need to controll more then 8 circuits with them.

That variable motor controller looks very interesting !

 

[fltcoils]

PCs used to have a "serial" output called RS232. Yours might also. There's an adapter to change this over to the industrial controller standard RS485 anatona makes it called the ANC-6085

Anyone recall setting serial ports to 8N1? So with that you send ascii strings to the port, and the controller reads them and executes the commands. Just like the old serial modems ..."ATDC 555-1212" etc when dialing up to compuserve.

I'd just assumed that your relay board worked this way.

 

[Unimatic1140]

More ideas and questions...

Fabulous Jeff, I was thinking of you and what you want to do to your Bendix and this Teco controller might be a good way to do it without a lot of computer programming. Might make for a fun dishwasher controller as well

Bill first let me briefly explain how I’m controlling the Super Unimatic. For my 2 relay control boards (each board contains 8 individual relays) I am using two separate parallel ports, one port for each relay board. I send an ASCII number through my visual basic program using the inpout32.dll. Relay board #1 controls the following functions within the washer by assigning the following ASCII number assignments to each individual relay:
Relay #1 is the Motor = 1
Relay #2 is the Spin Solenoid = 2
Relay #3 is the Heater = 4
Relay #4 is the Drain Pump = 8
Relay #5 is the Recirculation Pump = 16
Relay #6 is the Cold Water Solenoid = 32
Relay #7 is the Warm Water Solenoid = 64
Relay #8 is the Hot Water Solenoid = 128

So if I want to just run the Motor I send the relay board the number 1. If I want the machine to spin I send the relay board the 3. Because Motor = 1 and Solenoid = 2, so 1 + 2 = 3. So for another example if I want to wash with a heated reciruclation I want to run the Motor, Heater and Recirculation Pump. I would send the board the number 21. The number 21 is then sent via ASCII using the following syntax in Visual Basic:

DoThis = 21
Out Val("&H378h"), Val(DoThis)

The Val("&H378h") is the address of the parallel port that I want to send the number 21 out to, I have two choices since I have two parallel ports installed, either &H378h or &H278h.

Now onto our current discussion at hand…

Bill, thank you, I now realize you control this through the serial port. Visual Basic 6 comes with the MSCOMM control built in that allows you to pass ASCII strings to the serial port and out onto boards such as the Stratus. I assume you plug the adapter (that you posted a picture of) into the serial port of the computer and the other side of the adapter has a cord female jack that you plug a wire from the adapter into the J1 RJ45 jack on the Stratus board. Then all one would need to figure out is the correct syntax to use the MSCOMM module in VB6 to send string commands to adjust the frequency of the power to the motor.

Unfortunately in reading the PDF document, I see a challenge to this idea. The rated max start up current for the Status board is 10amps. Unfortunately the Unimatic’s start up current is 24amps. I don’t know what the startup amperage for a Rollermatic is but it should be significantly lower than the Unimatic because the Rollermatic mechanism employs a slipping clutch for power transmission, unlike the Unimatic which is a direct drive clutchless mechanism. I suspect though even with the clutch the Rollermatic will still draw 14-15 amps for at least 30 seconds during the start of spin when the tub is full of water. This will still overload the board.

The second challenge is just a thought and maybe my I’m incorrect in my assumption because I don’t know how the motor is going to behave when the frequency is dropped to less than 60hz. Maybe some of you guys know the answer to this… Generally most washing motors of this period use a start and run winding. The start winding is only in the circuit until the motor comes up to 90% of its full rated speed. The winding is cut out of the circuit by a centrifugal switch, so herein lies the problem… If we reduce the speed of the motor for a slower wash to 60% for example, the start winding will be energized during the whole cycle, wont this cause the motor to overheat?

 

[fltcoils]

start winding and overheating

I should mention that I really admire what you've done. 14 amps might be too much, but I thought there was some sort of a over current allowable if <1 minute.

I browsed some industrial sites on this, because it seemed like a problem. I didn't find out if the controller is so smart that it bypasses the centrifugal switch or what. They do claim some sort of a soft start feature, perhaps addressing this issue.

Did I mention some of the motor controllers can run the motor backwards? But perhaps only if its a 3 phase motor.

One forum I read said the voltage must = (base freq)/(nominal freq) * base voltage. Thus keeping the input power even (some formula proves this). So somehow controllers keep the input power constant to the motor. It caught my attention because as you exceed the 1800 rpm for a 4 pole motor the motor available torque drops. AT 3600 rpm one only has 1/2 the torque one has at 1800 rpm, given same power input. does that make sense? If one ramps the freq from slow to normal, in time with the normal accelleration of the drum spin, might that not prevent overheating? Eliminate the big phase error that builds up the heat in the laminations? But that might kill the torque, I don't know.

We used to control a bank of relays from the parallel port of a WANG computer, using a latching data holder chip and darlington pair of 2n2222 transistors to drive the relay coils. Used the same binary conversion system you do. I'm very familier with mapping desired relays into a binary word and translating into a ascii command string. I liked WANG basic. 5 banks of 16 relays to control the test cell. What fun when a power failure glitch occured and all 80 relays latched on! That would wake you up at 2 am as 30hp pumps with 350 deg jp4 screamed on full.

I've seen rs232 / rs485 relay modules, perhaps one could combine the motor controler and the relay modules together?