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Need to know the working voltage of the electronics in the Breville Smart Over 650. The power transformer has failed and I am looking for a replacement.

The primary winding of the power transformer on the oven's power board is open circuit. Breville has printed the component ID on the power board - TRA 201 and the transformer manufacturer has stamped the part number on the lamination: T28 0472. The smoothing electrolytic is rated at 25V so the board voltage should be somewhere between 6 and 12 volts DC. Could you please advise me the working voltage for the electronics, or the source for a replacement transformer? Thanks!

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6ya6ya
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Posted on Jan 02, 2017

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MicrowaveSvc
  • 9047 Answers

SOURCE: Samsung M1630 stepdown transformer details

That model doesn't show up at my normal Samsung US parts supplier. Can you post all the numbers found printed on the transformer? One of them should be the Samsung part number. Normally you can look at the voltage rating of the large filter capacitor on the control board and assume that the AC secondary voltage will be about 2V less (in ACrms) than that DC voltage. Now what I'm saying may seem a bit twisted - and it is - but what I mean is this: If the cap is rated at 15VDC, then I'm saying that a secondary voltage of about 13VAC rms should be a good safe level for testing. To confirm this, multiply 13VAC by .635 (assuming it uses a full-wave rectifier) and you get about 8.26VDC. Then allow for about 50% derating by mulitplying the 8.26VDC by 2. This gives you 16.5VDC, which with my generous derating, is pretty close to the caps 15VDC. Then you can remove the transformer and use an isolated Variac(tm) to apply that calculated AC voltage to the secondary connections at the circuit board to see if it powers up. You can measure the DC voltage across the cap as you adjust the Variac(tm), making sure you don't get too close to or exceed the DC rating of the cap. Once you get it working with a main DC voltage of about 50-75% of what's printed on the main electrolytic capacitor, you can start shopping for a sub transformer. It's much easier if it's not a VFD display which would require a separate filament winding, but there's nothing wrong with using a small second transformer for that. You can even mount them both on the chassis and run long leads to the board. As long as the leads are of sufficient gauge, routed and secured well, and protected from nicks, there's nothing worng with that technique. You should make them long enough that if the front panel is later removed for service, the next technician will be able to see the wires before he pulls them out or otherwise damages them. I would also add a varistor on the primary if there's not already one! *grin*

Posted on Nov 01, 2006

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MicrowaveSvc
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SOURCE: high voltage surge

We regularly repair these GE / Samsung boards from customers nationwide with just such problems for $32.50. If it's too bad off, we can get this board (# WB27X10466 remanufactured) for $145. A new board runs about $180. We would need the full model number with suffix.

Posted on Nov 01, 2006

  • 1 Answer

SOURCE: Sanyo EM-710F display dead

Low voltage Tx actually OK. Restored vaporised circuit tracks on controller board, fuse and interior light globe. All working OK.

Posted on Jun 22, 2008

MicrowaveSvc
  • 9047 Answers

SOURCE: HV Transformer and Maganatron

I would not recommend an inexperienced measuring secondary voltage on the high voltage transformer! The filament winding produces about 3VAC but the high voltage winding produces well over 2000VAC! And that can be instantly lethal!

I would only recommend measuring the resistance (in ohms) of the windings with power off and capacitor discharged.

We have the full service manual for this model and have uploaded it to our site here to help you.

You will need the free Acrobat Reader to view or print it.

The part number listed by the distributor for the high voltage transformer is RTRN-A527WRE0 (zero on the end, not "oh") which is the same number shown in the service manual.

The two continuity checks on a magnetron are across the filament terminals, which should read about zero ohms, and from each terminal to the case, which should read open or infinity.

Even if a magnetron passes these continuity tests, it can still be bad.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Posted on Oct 04, 2008

  • 50 Answers

SOURCE: No power on GE Profile Spacemaker II Microwave Oven

SWITCHES ARE THERE FOR A PURPOSE-----SAFETY,,SAFETY...ALWAYS CHECK A MICROWAVE WITH THE POWER CORD REMOVED---YOUR MESSIN WITH A RF VOLTAGE THAT WILL KILL YOU!!!! UNPLUG,,UNPLUG,,,UNPLUG
TRY TO CHECK THE FOLLOWING...SINCE YOU HAVE THE COVER OFF,,LOOK AT THE DOOR LATCHES WHEN YOU CLOSE THE DOOR AND MAKE SURE THEY MAKE CONTACT ON THE DOOR SWITCHES,,3 OF THEM,,,--AN OHM METER IS THE TRICK FOR THIS - SOMETIMES YOU CAN SEE PLASTIC BROKEN ON THE SWITCH ITSELF...ALSO LOOK AT THE COMPLETE SWITCH HARNESS (CHECK FOR BROKEN PLASTIC PIECES) THAT HOLD THE SAFETY SWITCHES...THE MIDDLE SWITCH (MONITOR SWITCH) CLOSES WHEN YOU "OPEN" THE DOOR,,YES "OPEN "THE DOOR AND IT WILL BLOW THE MAIN FUSE..IF IT'S SHORTED.

THERMAL PROTECTORS RARELY GO BAD--IF YOU HAVE A PROBLEM WHERE IT TAKES 25 MINUTES TO COOK A BAKE" POTATOE"--JUST LIKE THE VICE PRESIDENT--THAT'S A THERMAL PROTECTOR..
PLEASE BE CAREFULLLLLL TUNICA

Posted on Oct 30, 2008

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1 Answer

Panasonic NN-C2003S microwave is completely dead. No lights, no action. Have taken cover off and checked fuse, which looks like it is in good condition.


Would need to check power to main board. A lot of times it is the small low voltage transformer on the main board. If the primary winding goes bad it cant get power to the rest of the board to function. So to start, is there power getting to the low voltage transformer on the main board??Have you had any thunder storms or power surges at your home where it is plugged in? If a home loses its Neutral power line it can mess up a lot of electrical devices in the home. do you notice your lights browning at times. If so you may need to get your power company out to do a load test on you system. But the transformer is a very low amp device and will not blow the main fuse if it goes bad. So you could bhave aburnt trace on the back of the main board or a bad transformer. Best guess. Good luck

Jun 26, 2017 | Panasonic Microwave Ovens

1 Answer

Kitchenaid Superba KEMS307D Microwave buzzes, looks like it works, but doesn't heat. Full normal display, tray rotates, but fan doesn't sound normal.


Most likely causes - shorted high voltage rectifier, or failed high voltage transformer, or shorted high voltage capacitor, or shorted magnetron. If an odor accompanied the failure, high voltage rectifier or transformer most likely. All of these components operate on 4000 v, or more - with enough current to kill you. Make sure the unit is unplugged, and the high voltage capacitor is fully discharged before testing.

Apr 10, 2014 | KitchenAid Microwave Ovens

1 Answer

I have panasonic nn-gs597m microwave its working normal but not heating, I opened the cover magnetron is hot the fan is working. Any help?


follow the next steps , use the VOM and fix it. God bless you

Diode

The high voltage diode converts the A/C power output of the transformer to D/C, doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron which emits the energy that cooks the food. If the diode burns out, a lower A/C voltage reaches the magnetron, which is not sufficient to power the magnetron. When the diode fails it is often visibly burned out. If it appears to be good, it can be tested with a volt-Ohm meter capable of testing diodes. High voltage diodes frequently fail and are one of the most common points of failure in a microwave oven. A regular meter with a diode checker will not work to check these diodes. You have to use a meter with a 9 volt battery or put a 9 volt battery in series with the diode to check it.


f82cc372-4939-4661-9fae-8c3803e08e86.gif


Door Switch

If the microwave does not heat, one of the door switches might be defective. Microwave ovens normally have three door switches, if any of them fail the microwave does not turn on and does not heat. Check the switches for continuity with an Ohm meter.





Magnetron

If the microwave oven doesn't heat the magnetron tube might have burned out. The magnetron uses high voltage, high current DC power to generate the microwave frequency that cooks the food. If the microwave oven is turned on when it is empty this can cause the magnetron to burn out. Once it is burned out it has to be replaced, it's not repairable.





High Voltage Capacitor

If the microwave doesn't heat the high voltage capacitor might be defective. The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. If the capacitor is burned out the entire high voltage circuit stops working properly. The high voltage capacitor can be checked with a special VOM meter which has a capacitance testing capability. Be aware that the high voltage capacitor can retain a charge of more than 3,000 volts and can injure or kill a person if not handled properly. Only trained technicians should perform this type of testing.





High Voltage Transformer

If the microwave does not heat, the high voltage transformer might be burned out. Microwave ovens produce a very high voltage in order to power the magnetron antenna, which emits the energy that cooks the food. When a high voltage transformer fails it will usually arch and have a burning smell.





Thermal Fuse

If the microwave doesn't heat the thermal fuse may have blown. It can be tested for continuity. Watch our fuse testing video for more information.





Thermoprotector

If the microwave doesn't heat the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown.





Main Control Board

If the microwave doesn't heat the main control board may be defective. This is not common. When a microwave doesn't heat the problem is usually a faulty door switch or within the high voltage circuit; either the high voltage capacitor, diode, transformer or magnetron.

Jun 16, 2013 | Microwave Ovens

1 Answer

Some power but not operating


Check out with a multitester whether the control panel switch on the power towards the high voltage transformer NNB disconnect the high voltage transformer for this test. if not the relay on the electronic controlle device is broken and the panel needs replacement. check also the 3 safety switches on the door for proper operation. mind the power it is dangerous.

May 10, 2013 | Sanyo Microwave Ovens

1 Answer

Code f-33


Step 1:

Symptom: Intermittent or continuous error code F33 on the display. Cause: Insufficient (poor) grounding of the controller (DP) board.Remedy: clean the groundHowever if Not Heating proceed with the next steps.

1)Diode


The high voltage diode converts the A/C power output of the transformer to D/C, doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron which emits the energy that cooks the food. If the diode burns out, a lower A/C voltage reaches the magnetron, which is not sufficient to power the magnetron. When the diode fails it is often visibly burned out. If it appears to be good, it can be tested with a volt-Ohm meter capable of testing diodes. High voltage diodes frequently fail and are one of the most common points of failure in a microwave oven. A regular meter with a diode checker will not work to check these diodes. You have to use a meter with a 9 volt battery or put a 9 volt battery in series with the diode to check it.
Door Switch


If the microwave does not heat, one of the door switches might be defective. Microwave ovens normally have three door switches, if any of them fail the microwave does not turn on and does not heat. Check the switches for continuity with an Ohm meter.
Magnetron


If the microwave oven doesn't heat the magnetron tube might have burned out. The magnetron uses high voltage, high current DC power to generate the microwave frequency that cooks the food. If the microwave oven is turned on when it is empty this can cause the magnetron to burn out. Once it is burned out it has to be replaced, it's not repairable.


High Voltage Capacitor


If the microwave doesn't heat the high voltage capacitor might be defective. The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. If the capacitor is burned out the entire high voltage circuit stops working properly. The high voltage capacitor can be checked with a special VOM meter which has a capacitance testing capability. Be aware that the high voltage capacitor can retain a charge of more than 3,000 volts and can injure or kill a person if not handled properly. Only trained technicians should perform this type of testin
High Voltage Transformer


If the microwave does not heat, the high voltage transformer might be burned out. Microwave ovens produce a very high voltage in order to power the magnetron antenna, which emits the energy that cooks the food. When a high voltage transformer fails it will usually arch and have a burning smell
Thermal Fuse


If the microwave doesn't heat the thermal fuse may have blown. It can be tested for continuity. Watch our fuse testing video for more information.
Thermoprotector


If the microwave doesn't heat the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown.

Step 2:

2_7_2013_10_31_18_pm.gif2_7_2013_10_31_37_pm.jpg

Step 3:

2_7_2013_10_32_21_pm.jpg2_7_2013_10_33_32_pm.jpg

Feb 07, 2013 | Microwave Ovens

1 Answer

Neff gmbh microwave on but not heating


Step 1:

follow this steps and test and fix it. God bless you

1)Diode




The high voltage diode converts the A/C power output of the transformer to D/C, doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron which emits the energy that cooks the food. If the diode burns out, a lower A/C voltage reaches the magnetron, which is not sufficient to power the magnetron. When the diode fails it is often visibly burned out. If it appears to be good, it can be tested with a volt-Ohm meter capable of testing diodes. High voltage diodes frequently fail and are one of the most common points of failure in a microwave oven. A regular meter with a diode checker will not work to check these diodes. You have to use a meter with a 9 volt battery or put a 9 volt battery in series with the diode to check it.

Door Switch




If the microwave does not heat, one of the door switches might be defective. Microwave ovens normally have three door switches, if any of them fail the microwave does not turn on and does not heat. Check the switches for continuity with an Ohm meter.

Magnetron




If the microwave oven doesn't heat the magnetron tube might have burned out. The magnetron uses high voltage, high current DC power to generate the microwave frequency that cooks the food. If the microwave oven is turned on when it is empty this can cause the magnetron to burn out. Once it is burned out it has to be replaced, it's not repairable.



High Voltage Capacitor




If the microwave doesn't heat the high voltage capacitor might be defective. The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. If the capacitor is burned out the entire high voltage circuit stops working properly. The high voltage capacitor can be checked with a special VOM meter which has a capacitance testing capability. Be aware that the high voltage capacitor can retain a charge of more than 3,000 volts and can injure or kill a person if not handled properly. Only trained technicians should perform this type of testin

High Voltage Transformer




If the microwave does not heat, the high voltage transformer might be burned out. Microwave ovens produce a very high voltage in order to power the magnetron antenna, which emits the energy that cooks the food. When a high voltage transformer fails it will usually arch and have a burning smell

Thermal Fuse




If the microwave doesn't heat the thermal fuse may have blown. It can be tested for continuity. Watch our fuse testing video for more information.

Thermoprotector




If the microwave doesn't heat the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown.

Step 2:

2_7_2013_11_02_46_pm.gif2_7_2013_11_03_05_pm.jpg

Step 3:

2_7_2013_11_03_43_pm.jpg

Step 4:

2_7_2013_11_04_12_pm.jpg

Feb 07, 2013 | Microwave Ovens

1 Answer

Why is the microwave not heating the food, but the turntable is hot.?


Step 1:

folloq this steps and fix it. God bless you

1)Diode




The high voltage diode converts the A/C power output of the transformer to D/C, doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron which emits the energy that cooks the food. If the diode burns out, a lower A/C voltage reaches the magnetron, which is not sufficient to power the magnetron. When the diode fails it is often visibly burned out. If it appears to be good, it can be tested with a volt-Ohm meter capable of testing diodes. High voltage diodes frequently fail and are one of the most common points of failure in a microwave oven. A regular meter with a diode checker will not work to check these diodes. You have to use a meter with a 9 volt battery or put a 9 volt battery in series with the diode to check it.

Door Switch




If the microwave does not heat, one of the door switches might be defective. Microwave ovens normally have three door switches, if any of them fail the microwave does not turn on and does not heat. Check the switches for continuity with an Ohm meter.

Magnetron




If the microwave oven doesn't heat the magnetron tube might have burned out. The magnetron uses high voltage, high current DC power to generate the microwave frequency that cooks the food. If the microwave oven is turned on when it is empty this can cause the magnetron to burn out. Once it is burned out it has to be replaced, it's not repairable.




High Voltage Capacitor




If the microwave doesn't heat the high voltage capacitor might be defective. The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. If the capacitor is burned out the entire high voltage circuit stops working properly. The high voltage capacitor can be checked with a special VOM meter which has a capacitance testing capability. Be aware that the high voltage capacitor can retain a charge of more than 3,000 volts and can injure or kill a person if not handled properly. Only trained technicians should perform this type of testin

High Voltage Transformer




If the microwave does not heat, the high voltage transformer might be burned out. Microwave ovens produce a very high voltage in order to power the magnetron antenna, which emits the energy that cooks the food. When a high voltage transformer fails it will usually arch and have a burning smell

Thermal Fuse




If the microwave doesn't heat the thermal fuse may have blown. It can be tested for continuity. Watch our fuse testing video for more information.

Thermoprotector




If the microwave doesn't heat the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown.

Step 2:

2_6_2013_9_39_48_pm.jpg2_6_2013_9_40_27_pm.jpg2_6_2013_9_41_11_pm.jpg

Step 3:

2_6_2013_9_41_35_pm.gif

Feb 06, 2013 | Microwave Ovens

1 Answer

Unusual noise and electrical smell


If it's a burning odor, and there's a buzz, or a hum that's louder than normal, failure of the the high voltage transformer or high voltage rectifier would be the most likely cause. A failed rectifier usually looks like it's been hot - may have small bubbles on the surface, or may be discolored. A transformer will emit smoke when 120 volts is applied to the primary. Keep in mind that these things run on 4000 volts, or more. You can easily be electrocuted poking around inside when the unit is running (the capacitor may stay charged with 4000 v for weeks or months even when the unit is off). if you don't have a working knowledge of electronics / electricity, it's best to find someone who does. If the rectifier is bad, make sure you discharge the capacitor with a screwdriver from terminal to terminal, and from each terminal to ground. It isn't pleasant having a 4000 volt jolt of electricity travel through your finger. I know from experience. You finger will light up nicely for a second, though. It's kind of neat, but painful!

Dec 27, 2012 | GE JVM2050 Microwave Oven

1 Answer

Microwave will not heat up although grill in m/wave is ok-it is a Breville BRE997SSG


It sounds like the magnetron may have either failed or is not being supplied with the extremely high voltage required to run it.

YOUR SAFETY IS PARAMOUNT

This is a job for a professional but if you are safety clued up, here's instruction.
Make sure the !!!!capacitor is discharged!!!!! before attempting any sort of repair.
Check the door interlock switches first then the high voltage diode with either an AVO model 8 or moving coil meter on high resistance range for short circuit, (DVM's won't show the fault!), the capacitor can fail and go short circuit, the feed fuse on the primary of the high voltage transformer and then finally, the magnetron is best checked by substitution.
Hope that helps.

Jan 06, 2011 | Microwave Ovens

2 Answers

Danby 1000 Watt Microwave is completely dead. Just stopped working right after heating up a dinner.


you may have just blown a fuse inside the microwave or the transformer inside has now failed and will need replacing but it will need to be looked at to see what exactly happened

electech

Nov 27, 2008 | Microwave Ovens

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