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Just installed new power supplies. Rewired pretty much everything power related ensuring that the PSUs get beefy supply wires and 20 AWG for the motors from PSUs.

PSU1 - X axis
PSU2 - Y axis
PSU3 - R + Z axis

What a difference! The machine runs smoothly and so quiet now! I used to get annoying buzzing just by using test controls to move the arm by 1500 and now it's gone.

Need to sort out the LED power supply and all should be done and dusted. BTW, the veroboard powered the LEDs both for fiducial correction and vertical facing static camera.

Thanks for all your help! Will be doing board placement next week to put the machine to a real test.

I think I've got the veroboard reverse engineered now. It's basically a DC-DC power converter that drops the 36V to 12V for the LEDs on the fiducial correction camera. That's pretty much it. The motor controllers essentially don't use any of this. They are powered like this:

Mains Power -> Toroid -> diode bridge -> 12000uF cap -> motor controllers



Mains power in the nineties must have been very stable when they were designing this machine...

Mike, I was considering TDK-Lambda, but decided to try out Meanwell. Considering that TDK-Lambda are priced £200+ for the specs needed I ordered four RSP-320-36 for £44.50 + VAT each. They have PFC and with 8.9A max rating each they should be more than enough for the requirements of the machine. Here's the link to the product page with specs:

http://www.ecopacpower.co.uk/mean-well-power-supply-rsp-320-series-150w-320w-3-3v-48v-8693.html

They have higher spec alternative twice the price, however there is a 2-3 week lead time which I can't wait. I decided to go with multiple PSUs in order to distribute the load as I think it will be healthier for the motors to be on separate power supplies instead of just one. Motors are rated at 1.5A so it may seem like an overkill, but I want to upgrade the machine once and forget about it!

I really can't wait to see my machine working properly probably for the first time since I got it!

Just hooked up the machine to a lab power supply. To be honest, it's the first time I heard it running so smoothly!

Ok, looked through the datasheets. One of the amazing features is "Low Cost!!" Wonder why just two exclamation marks?

Anyway, found a few power supplies that should be suitable. They are rated at 9A nominal output current and have way more advanced features. The ones that originally came in your machine seem to have a feature for "Applicable to peak output wattage 200%" which sounds dodgy... There is also a limitation of 10s duration at peak current. I think that's why they are sort of suitable for the machine as all steppers do not run at 100% all the time and you just get power spikes when the arm moves around.

If I stick power supplies with nominal current way above required by the machine I think I should be on the safe side. Plus I'll be putting 3 PSUs instead of just two.

Having had so many power supply wiring problems with this very old model I just want to completely get rid of this issue and have the machine running at full speed reliably. I really like RV1S, just hoping that one day I can find an RV4S for an upgrade

Fingers crossed as I should be receiving a lab power supply today so should be able to check really quickly whether it's actually PSU problem. Will keep you updated.

Yes, I think you are right! I'll reverse engineer the veroboard to make any sense out of the circuit.

phonoplug, thanks! You are amazing

I ordered a 10A lab power supply yesterday just to test the theory that PSU is causing all my troubles. Have been shopping for a permanent solution around so thanks very much for the tips! I'm even thinking of getting 3 power supplies: one for X, one for Y and one for R+Z. My only concern is whether I need any additional set of circuitry which is on the veroboard between each PSU and motor drivers. I'm good at MCUs, but motor drivers and their power supplies is something new to me.

Decided to get to the bottom of this as I have been using the machine a lot more recently. I still have this annoying buzzing sound as mentioned a while back especially when the machine goes full speed. I beefed up all power cables (like to an insane level), replaced all electrolytics, checked all the wiring, tested hybrids with multimeter and everything seems in a solid shape however the buzzing just wouldn't go away! Hooked up main power rail to a scope and just as Jason reported in one of my other threads I have a nice 4V ripple and a voltage drop of 7V on occasions just by running warm up procedure. Can't hook it up to a bench PSU to test the theory as mine goes only up to 20V. I want to completely get rid of the toroid and the crappy veroboard and replace them with proper switch mode PSUs.

• Do any of you guys have a spare power module for sale? If not I might reuse the veroboard, but I don't have much faith in it :-)
• I remember one of you mentioning that newer models have two switch mode PSUs. Maybe somebody would be able to provide me with model numbers of those? Thay are supposed to be rated at 36V if I understand correctly, but what is the amp rating on them?
• How are they connected to the controller boards? X+R and Y+Z or something similar?

Thanks for all your help!

For my RV1S upgrade I just bought a completely separate PC with ISA slot and set everything up on it. The one that came with my machine was seriously underpowered anyway. The only thing I had to do was to plug the ISA motor controller board to the new PC once I have everything set up. I highly recommend doing it the same way.

Already replaced the electrolytics on the power board and did the rewiring, but that didn't help much. Placed almost 4000 components today with minimal rotation issues. Yesterday with identical setup had componwnts rotated all over the place...

So I have this very old RV1S with toroidal transformer and veroboard based power supply circuitry. If you remember I mentioned that I have issues with random rotation of placed components. Been placing about 12 panels yesterday with about 200 components each and most of them had random rotation issues especially with 0603 caps. Came in today and the machine has been placing 4 5 panels so far with 0 issues and correct component angles. The only difference between yesterday and today is that I am working alone in a rather large office building.

Mike mentioned in one of his post that toroids work just fine unless mains voltage is unstable and I think I do have unstable mains when office building is full. What would be the best option to mitigate this issue? I'm thinking of either replacing the toroid and veroboard with a couple of high quality switch mode PSUs of just buy a high quality UPS that would also act as backup power in case of power failure.

I would probably prefer a UPS solution as it's very easy to install and I wouldn't have to bother with PSU rewiring. From what I've read on the internet, I need a high quality PSU that would also stabilize the mains power. Would any of you have suggestions on what I should purchase?

Thanks in advance for your help!

Arvy

I'm still having buzzing issues on the X axis and will check the power with a scope.

Before I purchased my RV1S, I was considering building a machine myself as XY frames are quite cheap, however the only thing that stopped me was the general complexity of automatic feeders. That alone seemed like a too big of a time investment not considering the software alone. Yeah it should be possible to do pick and place from passive feeders, but looking after them would be too much of a pain. Effectively buying a used proper pick and place machine seemed to be the best investment I've ever made so far.

Makerarm seems like a nice toy. At least they have reasonable shipping estimates. Looks like a toy that is supposed to do everything, but the question remains if it's going to do at least one thing properly :-)

Just replaced all of the connectors and wired each motor driver directly from the power supply. Hooked up to the machine and the X axis buzzing is completely gone! The Z axis no longer has this very loud buzzing sound too which I thought was normal for the machine. I'm now certain Z axis was the last in the chain and it got the least amount of power which made it struggle to run the stepper motor. Still managed to place though. Now all axis movement is as smooth as it should be.

Finally I need to zip tie everything back to be safe and secure and should be back in business! Thank you so much for your help guys, you are awesome!

Wondering if it would be worth for me to improve the power supply for the motors. Would like to eventually get rid of the toroid and silly veroboard. Is it possible to acquire the power supply together with power module for the machine? Wondering if it's even worth doing that if machine will be running just fine.

Ordered a bunch of crimps, housings and replacement header for the 12 pin on the driver board which got badly damaged. Decided to go with the Molex parts that are supposed to mate correctly with the headers.