Shopsmith Forums

I have a toaster oven that is well cared for and yesterday it went south. Had to use three different screw drivers (two which most people don't have)to open the case. I think they do this to prevent repair. The picture shows a burned diode (?). Number is 5408 PY. Once I could go to Radio Shack and buy one. Internet was no help.

Where can I buy just one?
I don't have crimp connectors shown in lower left. Can I solder this or do I need to crimp them?
If I need crimp connectors where can I find those.

I went to google and used "diode" and the part number and got a lot of answers. From what it looks like it is a common part 1N5408. You can check the specs and find a replacement a lot of places.

They make sleeves that allow you to crimp the wires together. You might need a crimp tool to do it right.

While solder might work make sure you have a mechanical connection as well. Twisting might be the easiest.

Ed

This one should work for you. The generic part number is 1N5408. PY is likely a manufacturer-specific code (e.g. for packaging details).

Be aware that the blown diode is very likely to be a symptom, rather than a root cause. If so, the same fate will befall the replacement diode.

I do not think toaster and solder is a good mix.

What else is in there besides the two diodes?

What is the function of the diodes?


i.e. Is understanding of why it failed present?

JPG wrote:What else is in there besides the two diodes?

What is the function of the diodes?


i.e. Is understanding of why it failed present?

One diode is connected to the upper heating elements the other to the lower. Neither element is on with the blown diode.

Here are some pictures: It has three controls (from left to right)- Timer, Function (toast, bake, broil) and Temperature.

I have no training in electrical stuff other than self-taught to fix stuff. So, I haven't a clue as to why it is blown.

There are a number of videos on Youtube concerning toaster oven repair. You might find help in one or more of those. I would look for any signs of components getting hot (melted plastic, scorch marks etc.). That could lead you in the right direction. Also, you will probably need an ohmmeter to test components.

Well that is certainly an interesting way to terminate the diodes!

I question why they are there(if they indeed are in series with the heating elements).

It appears they are connected in parallel to each other.

I will hazard a guess that the other one is 'open'.


IIWM(and that above is accurate) I would replace them with one diode with greater current handling capability.

I be assuming the heating elements are 'resistive'(nichrome).

Forget the diode fer the moment.

Put that red thingey on the temp control silver tab.

JPG wrote:Forget the diode fer the moment.

Put that red thingey on the temp control silver tab.

toaster fix.jpg

Yes, I know it belongs there. I removed it to get access to the wires and find the numbers on the diode. Pretend you are dealing with someone who has never read "*** for Dummies" and you don't have access to this oven, what would you suggest?

Referring to pic "diode2" is the orange wire just below the blown diode burned?
In pic "diode1" there appears to be a scorch mark on the white wire left of the diode. Correct? Or not.
The diodes can be replaced by replacing the two crimp connectors and squeezing the diodes leads in the openings of the female spade lug connectors and then soldering for a good electrical connection. The diodes seem to only conduct current on one half of the AC sine wave. This would limit the total continuous current to about 16 milliseconds at a time. The elements will not get as hot as full time continuous current but hot enough to still get the unit up to temp.
Definitely check the other diode and replace both if you want to. I would suggest that. Sometimes components just fail. As a precaution I would check for a short from the heating elements to ground.
With the two diodes in parallel, the current will divide to flow through the two diodes and the diodes will dissipate half of the heat and last longer. If , as JPG has suggested, the unbroken diode may be open, all of the current would have to pass through the remaining diode and cause the apparent catastrophic failure.

Bill V