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Are all microwave oven diodes not the same?

Are all microwave oven diodes not the same?

Okay so diodes depending on what brand they are "made for" such bs, range in price between $3 and $40

ANSWERS:

"Hi,

The big deal about capacitor discharge and voltage is that not everybody knows what they are doing and why it has to be done in certain ways sometimes. Not their fault, they just haven't been trained. Because of this they may injure themselves and they could also create more damage in the appliance.

They think that electrical/electronics repair is easy. ""It's probably only a fuse"", simple. The litany of problems caused by DIY repairs in this forum is proof that it is not as simple as it sounds

Shorting out a high voltage capacitor incorrectly could possibly lead to sparks flying causing flash blinding. If not using the appropriately insulated tools could lead to electric shock and depending on the person's medical condition could even be fatal.

One example that I've seen is a screwdriver welded across the capacitor terminals because it wasn't big enough to handle the current flow and melted. They just heard ""short it out with a screwdriver"" and grabbed the first one to hand. As you can see what may be obvious to you is not necessarily obvious to somebody else.

The correct way to discharge a high voltage electrolytic capacitor is to connect the +ve terminal to chassis Earth via an appropriate high value resistor (MegOhm), with the correct power rating. to limit the amount of discharge current flow. Then when satisfied that it should be mostly discharged apply a s/c across the terminals to doubly ensure that it is.

Sounds unnecessary but not only is this the safe way to do it, it also prevents possible damage to the capacitor due to high surge current flowing.

It only takes a few minutes but I guess impatience wins out, hence the screwdriver

The fact that you can get away with using a screwdriver is testimony to the robustness of the component but again all are not equal.

Update (04/06/2018)

Hi,

To my knowledge there is no ""standard"" diode for microwave ovens.

I would have thought that their rating will differ depending on the design of the circuit.

I'm not in the repair business and have only replaced 2 diodes in my time, whilst fixing microwaves as a favour. More often it is the turntable drive motor or the control panel that I've had to deal with.

I just used what the microwave oven manufacturer listed in the parts section. After all they know their product best.

As to the price, once you know the diode specs (or type number or equivalent) you can search online to find suppliers and also the manufacturers (brand) of the diodes. (Try mouser.com, farnell.com, element14 -I'm sure you have your own preferred suppliers). Knowing the manufacturer (brand) is sometimes helpful as you can then check their ""reputation"" to see if their components are quality products or just so-so, This used to be the case with capacitors as you're probably aware.

It may be that it is better to pay a bit more for a part if you know that it is going to last the distance rather than have it fail prematurely because the quality is not there.

Sorry that I cannot be of more help."

Diodes are rated for the wattage, or amperage that they will be allow to pass, or breakdown safely within the component. Some of them may look alike on the outside, but their internal characteristics may not be the same. Pretty much like a fuse. You wouldn’t use a 1 amp fuse in a circuit if the transformer in front of it is constantly putting out 10 amps. The existing fuses may look alike, but the 1 amp fuse would blow every time the circuit was turned on. Read the label. Usually your HV diodes will be marked also. However, that is when you will have to research the specs on that particular diode. Depending on the HV capacitor, a CL01-12 diode will usually handle about 12 KVolts at a maximum of 350 mAmps. Many of these type diodes are common in the lower powered Microwaves. However, as the wattage of the newer Microwaves gets higher, the HV diode must meet the requirements of the circuit to work without breaking down too early, or failing entirely. I have seen some of the higher rated Microwaves blowing the CL01s, and working using CL04-12 diodes only rated at a little higher, 450 mAmps.

"Yes makea sense I've run into many who think that whatever they can get away with is the correct fix.instead of acquiring the tools and education required. One of my clients changed a dvdrw drive as computer was running another a expansion card. There is no end of ....

My Question:

So I've never repair a microwave oven only tv's and entertainment related consumer electronics .

Is there a standard diode

Or

Do they have values depending on microwave power output rating ie 900w 1000watt?"

"I used to repair cardiac defibrilators and we discharged the giant capacitor used in them with a high voltage probe, The high voltage probe was originally used to measure the CRT votage on the side of a CRT. It looked like a long plastic wand with a metal tip and plugged into a dvm. It had very high resistance so it could bleed down the voltage slowly.

Here's one on amazon: https://smile.amazon.com/Precision-PR-28...

As crts are rare you might find one cheap now."

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