Inverting PS_ON levels

[Nxt-1]

@tomasf said in Inverting PS_ON levels:

I had the same problem and solved it with a simple 7400 NAND gate chip: https://forum.duet3d.com/topic/412/inverting-ps_on

I got myself a couple of 74HC00's to plat with. I assume you you wired your system like this? What value did you use for the pull up?

[SW]

Hy, I have an Meanwell PSPA-1000-24 and removed the bridge from the power supply. Then I connected the contacts "Ground" and "PS_on" to the power supply and connect an small 5V power supply (Jumper 5V ext!). If you switch the ATX-Power on (M80) the "PS_on" is connected to the "Ground".

It works fine!

[Nxt-1]

@sw said in Inverting PS_ON levels:

PSPA-1000-24

A quick glance at your PSU's datasheet shows that it's RC logic is inverted compared to most Meanwell's, thus making it directly compatible with the Duet.

[Nxt-1]

@nxt-1 said in Inverting PS_ON levels:

@tomasf said in Inverting PS_ON levels:

I had the same problem and solved it with a simple 7400 NAND gate chip: https://forum.duet3d.com/topic/412/inverting-ps_on

I got myself a couple of 74HC00's to plat with. I assume you you wired your system like this? What value did you use for the pull up?

I eventually decided to go with a 10K resistor and all seems to work as expected. I will have to get myself a small proto-board and wire things up neatly.

[Nxt-1]

I got wired soldered up the proto-board and decided to use the auxilary 5V from the 24V PSU as I was already using the relevant connector. This results in a layout like below (unused gate input are tied to ground).
The solution is neat and compact, yet as I test it on my machine I find out that the AUXG terminal is not connected to the other grounds (not 240V L-, nor 24V V-). As a result there is to connection between the ground this circuit uses and the ground the duet used for the PS_ON pin. Back to the drawing board I go!

[Nxt-1]

Since the AUXG and RC- terminals are already internally connected according to the datasheet, I decided to add a ring terminal to one of the ground wires I had. That connecting was then connected to V- and now all grounds are connected.
The system works fine now

[Selecta_Mota]

Hey there
I have the same problem with the RSP-500 from MeanWell.
Is there no chance to change the firmware?
So M81 pulls the pin to GND and M80 opens it?

[Nxt-1]

@selecta_mota said in Inverting PS_ON levels:

Hey there
I have the same problem with the RSP-500 from MeanWell.
Is there no chance to change the firmware?
So M81 pulls the pin to GND and M80 opens it?

Sadly software changes cannot compensate for things that are not there in hardware. A quick look at your PSU's datasheet shows me that its ON/OFF logic is reversed from mine's. Are you sure you cannot use it as is, maybe with a pullup in there?

[Selecta_Mota]

@nxt-1 the remote is a little different on the RSP.
I need 4-10V to turn the PSU off and anything below 4V to turn it on.
When there is nothing connected to the pins on the RSP it is on, when it gets GND on pin3 and 5V (from the external 5V supply) on pin4 it turns off.
So I just need the outputs of M80 and M81 commands to be switched.

[fma]

The Meanwell logic is a non-sens: if the 5V is lost, the power supply turns on! Looks very dangerous to me...

[Selecta_Mota]

@fma said in Inverting PS_ON levels:

The Meanwell logic is a non-sens: if the 5V is lost, the power supply turns on! Looks very dangerous to me...

Yeah, I know its kind of awkward but its the only PSU I could find with a bult-in remote.
It cant be that hard changing the firmware from 1 to 0 (at least thats what I hope):

[dc42]

I have it on my RRF 3 work list to add a parameter to M80/M81 to allow the sense of PS_ON to be inverted.

[marvineer]

@dc42 said in Inverting PS_ON levels:

I have it on my RRF 3 work list to add a parameter to M80/M81 to allow the sense of PS_ON to be inverted.

Hi dc42!
Is there anything new to this topic on your work list?
For me it would be extremely helpful to just reverse the pin-logic in my config file somehow

[oliof]

It's on the planned 3.2 feature list.

[justus2342]

For anyone still looking for a simple solution for those Meanwell RSP Power Supplys. Here it is.

I implemented and I tested this with my Meanwell RSP-500-24 Power Supply. It works perfectly as intended.

There is also a PCB-Layout, but I have not implemented it yet and hence it is untested.

[oozeBot]

@dc42 said in Inverting PS_ON levels:

I have it on my RRF 3 work list to add a parameter to M80/M81 to allow the sense of PS_ON to be inverted.

Will this make the cut for 3.2? Fingers crossed..

[BoA]

@justus2342 Why there is an ext 5V input, while Mean Well RSP has 12V STBY line availabe?

[justus2342]

@BoA said in Inverting PS_ON levels:

@justus2342 Why there is an ext 5V input, while Mean Well RSP has 12V STBY line availabe?

I am not sure if we are talking about the same PSU.

I am using the RSP-500-24. In the data sheet I cannot find any information on a 12V STBY line. This is the data sheet:

https://www.meanwell.com/webapp/product/search.aspx?prod=RSP-500

[BoA]

@justus2342 OK. Seems not all RSP were create equally I use RSP-750-24 and it has 12V 100mA STBY power line

[GoremanX]

@dc42 said in Inverting PS_ON levels:

I have it on my RRF 3 work list to add a parameter to M80/M81 to allow the sense of PS_ON to be inverted.

I'm not seeing any mention of it in the beta changelogs. Does this mean it didn't make it into the upcoming release?