Random flashing led smart effector

janb

If purchased a smart effector. When powered the green led flashes twice but after a few seconds the green led randomly flashes continue. When I touch the heat sink or heater the led get continue on even when I approach the effector whith my hand within af few centimeters the led turns constant on. Everything ( heater, thermistor, fan) works fine accept the flashing led. At last I removed all connections from the effector and only powered the probe connector (INPUT 2) with the 3.3V output from the duet probe connector. The problem stays. What’s wrong?

dc42

Assuming you don't have a large coil carry AC mains current, or a radio transmitter or similar in the immediate vicinity, or a lot of vibration, then I think your Smart Effector is faulty. Please ask your supplier to replace it.

Quadcells

Hi,
I have had my Smart Effector since Febuary 2018, The Z-Probe led started Random flashing and cannot auto cal.
What can I do?

dc42

First check whether there is a bad crimp connection in the +3.3V or the ground wire in the 8-pin connector.

Quadcells

The 3.3v looks stable at the connector on the effector, but I am going to re-do the crimps and see what happens.

Quadcells

I have the same results:
Turn on printer, green LED flashes twice, then a few seconds later the green LED just randomly flashes. A weeks ago I had posted that I was not receiving any measurements after sending command G30 S-1 but that suddenly worked after a reboot. Not sure if the two are related.

dc42

Has there been any damage to the strain gauge traces on the PCB?

Quadcells

is the strain gauge traces the ones that go from r11 and r13, if so I measure 46.4 ohms.

dc42

That's one of them. The other goes between the same point on R11 and one end of R14. Schematic at https://github.com/T3P3/SmartEffector/blob/master/SmartEffector/SmartEffector_v1.3/SmartEffector_Schematic_v1.3.pdf. Both strain gauge traces should have approximately the same resistance.

Quadcells

R11 to R14 is 16k ohms , R11 to R13 is 47 ohms, problem:(

dc42

R14 to R11 is the strain gauge trace on the top side of the PCB. Can you see any damage to it?

Quadcells

@dc42 sadly I do. I must of scraped when I re-assembled the hotend after a jam. I have to be more careful in the future.
I can order a PCB from Filastruder, better than buying the whole setup.

dc42

@quadcells, if you can see the damage and it is localised, and you have a fine-tipped soldering iron, it might be possible to repair it by soldering a single strand from some stranded wire over the break. The traces are only 0.15mm wide, OTOH I've hand-soldered 0201 SMD components (0.25 mm × 0.125 mm) before now.

It would probably be OK to paint some polyurethane varnish or similar on to the PCB to help protect the traces in future.