PS_ON, relay SSR-40DA LED strip

PuG · 18 Dec 2018, 09:41

Good morning, just adjusting my Duet2 Wifi so it can turn on the LED Strip PSU.

I bought a SSR-40DA relay but I don't think there's enough Ma to switch it successfully?
Its connected to a 5+ vin to + on the SSR and PS_ON for earth.

Input:
3 - 32 VDC
Control current 5 - 25Ma

When I trigger PSU on through the interface with my meter I can see voltage going to the relay. Relay does work, I've manually got it plugged into a spare computer PSI 5v line to keep it switched on.

Any suggestions?

Thanks, James

PuG · 18 Dec 2018, 10:58

Problem solved, it would help if I actually plugged in the power supply after swapping the leads over. Yes I did check but I put it down to the human condition.

Running the +5 from a always on fan, if the fan VIN is set to 24 volts rather than 5v on the jumper will this damage the PS_ON pin?

Cheers,

dc42 · 18 Dec 2018, 16:15

@pug said in PS_ON, relay SSR-40DA LED strip:

Running the +5 from a always on fan, if the fan VIN is set to 24 volts rather than 5v on the jumper will this damage the PS_ON pin?

If you mean can you safely connect the SSR input terminals between +VIN and PS_ON, the answer is yes. The PS_ON pin is an open drain output rated at 40V, and most SSRs tolerate anything between 3 and 32V input.

LHelge · 19 Dec 2018, 11:38

I've had a similar thought. In my printer I have a 24 V 200 W Meanwell PSU for the duet (steppers and hotends). I also have a smaller 50 W meanwell with 5V and 12V output. Right now I Only use the larger one, but I would like to connect a constant feed to the duet. Would it be possible to do like this:

Small PSU with constant power, feeding 5V to Duet and 12 V to a few LED-strips and the positive control input on a SSR.
The negative feed on the LED-strips and the SSR connected to PS_ON pin.
This SSR turns on power to the main 200W PSU and the SSR controlling the mains powered heatbed.
Heatbed, small PSU and large PSU each have separate fuses on mains power.

Then the PS_ON pin would turn on the LED-strips and enable power to both the heatbed and themain PSU.

Would this work?

dc42 · 19 Dec 2018, 13:58

That would work if the LED strip current isn't too high. The PS_ON pin isn't designed to handle much current, but it should be OK up to 1A.

Alternatively, use 24V LED strips, then you only need to have 5V standby power,