Protection diode fried

[alexishh]

Hi

We had a switch in a tower that had lost power.
While investigating whether it was due to the battery regulator or the switch itself, we happened to hook up backwards the WS-12-250-DC switch, and could see a component fry near the power supply terminal.

As per this post viewtopic.php?f=6&t=1678&p=12438#p12438 that must be the protection Diode.

I suppose doing so we voided the guarantee (and will have trouble telling if the switch ever had a problem before we did so).

Anyway, being in France we would rather try repairing it ourselves than sending it back to the US. For that would it be possible to know the precise reference number of the Diode so we can replace it ?

[Julian]

On the power supply (rear board in chassis) the protection diode is directly between the red and black screw terminals, and labeled 'D1'. This part can be replaced with any transient protection diode comparable to http://www.digikey.com/product-detail/e ... ND/3306594, making sure that in normal circuit operation the diode is reverse biased (cathode toward red screw)

There is a better than even chance that replacing just that component will not restore your power supply's functionality.

After you remove the damaged diode, Do two things:

1: check continuity across the white fuse labeled F1. If this has blown, there are more problems with your circuit, and it will require an RMA to troubleshoot, or maybe we can send you a new power supply board for a fee.

2: reassemble the unit and carefully apply >9v with the correct polarity. If the protection diode is the only failed component, the power supply will begin to power the switch board. Do not deploy your device if it is missing this protection diode, it is a very necessary protective measure and your device will fail without it.

If your switch board powers on without D1 populated, you should be okay after replacement; If it does not, there are further issues with your device which will require an RMA to troubleshoot, or, again, we can possibly send you a new power supply board for a fee.

Let me know how you make out, feel free to email, my address is julian@netonix.com. Best of luck!

[alexishh]

Indeed F1 has blown, we replaced it and applied 24V to the power supply board. We checked it still seems to perform normally, also checked the output voltage was right.
So we plugged it back into the unit and so far it works :) Phew!
Next we'll find a diode and a better suited fuse and replace them before deploying.

Is there anything else we should pay attention to? We only let it on 2 minutes to boot and shut it down.

Thank you for your great answer

[Julian]

I'm glad it works, you definitely got lucky there.

The fuse you're looking for is a bel 30a surface mount, part number SMM 30, and can be ordered from digikey or a regional supplier in your area, the digikey ordering link is http://www.digikey.com/product-detail/e ... ND/2440246.

If you're up and running, it's safe to say that protection was sufficient in this case; should work just fine now. Make sure you replace that diode with the proper orientation, and you should be fine.

You're quite welcome, we strive to offer exceptional support for our devices. I'm pleased I was able to help.

[sirhc]

Since you have it open you might as well apply this MOD: viewtopic.php?f=17&t=2584

[Asuinetwork]

What if high Dc voltage was apply by mistake am in the same boat as well since am in Trinidad 84 volts was applied by mistake and i void the warranty by removing the sticker nothing seems burnt and would like to fix myself fuses seems good D1 diode seem OK any help would be nice, when power was apply there was a spark not from the system but connecting the power wires [img]file:///C:/Temp/IMG_20171026_212314.jpg[/img]

[Asuinetwork]

I got the WS-8 150 DC REV G

[sirhc]

What if high Dc voltage was apply by mistake am in the same boat as well since am in Trinidad 84 volts was applied by mistake and i void the warranty by removing the sticker nothing seems burnt and would like to fix myself fuses seems good D1 diode seem OK any help would be nice, when power was apply there was a spark not from the system but connecting the power wires [img]file:///C:/Temp/IMG_20171026_212314.jpg[/img]

Well the fact that you applied 84V voids the warranty so removing the sticker is insignificant.

When upload pictures follow the instructions in my post footers because we can not see pictures located on your local drive "C:/Temp/IMG_20171026_212314.jpg"


There is an Upload attachment link below the BLUE SUBMIT button for uploading pictures.

I am pretty sure the voltage regulator chip is fried as that is way beyond its upper limit but Julian or Dave can weigh in here.

Could we repair the power supply...."probably", "maybe", is it worth it though?

You can RMA the unit and send via postal mail.

[Asuinetwork]

I would just replace the board can i order the board and how can i obtain it ?

[Asuinetwork]

all diode seems fine mosfet seems ok fuses are ok