Custom Control for Unimatic

[lebron]

Hello all. The timer on my 1955 Unimatic was toast so I decided to wire up my own semi-automatic control. The first picture is the wiring of the control board and fuse. This entire thing is serviced from the original motor protector switch. I know little about electricity so I'm sure it could have been done a lot better, but I just wanted to throw this together to see if it would work. The washer seems fine and functions just like a normal Unimatic. Is there a backplate for behind the console? I wish I knew more about electricity and computers, but I had an idea. This is controlled by manual switches. Instead of a board of toggles could I have a board of relays? How can I control the relays then with a computer? I would probably need my own little 12V system that could interface with a computer program. Fun to dream if I had more time and resources

 

[lebron]

Feel free to check out the videos.

 

[lebron]

Does anyone know how many amps a Unimatic draws during spin startup?

What about during full speed spin?

And finally agitation?

I assume it would actually draw more amps during agitation than once it is spinning full speed?

 

[eddy1210]

 

[bajaespuma]

Brilliant!

 

[turquoisedude]

Wow!  I love the idea of an 1140 rpm spray rinse.   Great job, Jed!

 

[swestoyz]

Hey there Jed,

Great start so far! I've been using the following relay when restoring Unimatics, to control the motor via the original timer. It's listed at 30A @ 240v, which is plenty sufficient to carry the load for the transmission and moves the heat/current load from the delicate timers to these heavy-duty and easily replaceable relays.

https://www.grainger.com/product/OMRON-100-120VAC-4A711

Omron PN - G7L-1A-TUBJ-CB-AC100/120

If you are planning on having a low voltage controller/PC interface in place, I'd look at this 12v DC relay for the motor -

https://www.grainger.com/product/OMRON-12VDC-1YCX3

Omron PN G7L-1A-TUBJ-CB-DC12

For the water valve and the spin solenoid, you can probably get away with a relay that's rated at 10A 120v to control those devices.

Good Luck!

Ben

 

[jimmler]

A couple controllers come to mind that are affordable and fairly easy to learn: Arduino and Raspberry Pi
There is tons of info and interface boards available for both platforms. You could even hook them up to the Internet and control them remotely, etc. I thought about doing this with my Maytags, but they are my daily drivers, so I'm a bit skittish about messing with them.

Good luck!

 

[jetcone]

I totally forgot about Roberts’

Rah-Hah Frigidaire test !! What a throw back! Nice Revive Eddie !!

That first machine is a Unimatic and it drew between 25-26 amps. The second machine, it is a Pulsamatic different altogether it drew 12 amps at spin-start before the start winding cutout.

I have tested several of my Unimatics and found the draw to be 25-26 amps in spin-start— HUGE !!

So that relay Ben pointed out will work just fine. I put one in my 57 Charcoal washer as the timer contacts were overheating on spin-start and that relay now lets the timer run cool and smooth