Flyback Voltage Spikes Emitted From an Unprotected Relay

  • Thread starter Thread starter CAMTWO
  • Start date Start date
  • Tags Tags
    Relay Voltage
AI Thread Summary
Unprotected relays in automotive wiring harnesses can cause significant issues, including damage to sensors and ignition modules due to flyback voltage spikes. The discussion highlights the importance of using protected diodes in relays, as switching to protected relays resolved multiple problems for the user. There is a contention regarding the responsibility for these failures, with accusations directed at wiring harness manufacturers and installers. Experts note that many automotive relays lack flyback protection and emphasize the need for builders to improve their products to avoid such issues. The thread ultimately faced moderation, leading to a ban for the user due to repeated posts on the topic.
CAMTWO
Messages
2
Reaction score
0
TL;DR Summary
Had an issue with electrical gremlins and blown sensors also 3 ECU's after buying a wiring harness from a Veteran in the industry. Back when this guy started Flyback wasnt even considered and besides the harnesses are installed in kitcars and hotrods built all around the world.All these wiring kits are plagued by flyback emitted from the huge amounts of cheap unprotected diodes they utilize. My ECU expert said I was spiking the heck out of my ECU with flyback due to lack of circuit protection
I research the phenomenon and came up with the fact they weren't using protected diodes in their relays they utilize in a multitude of wiring harnesses for cars and also go into factory built kitcars in massachusettes..

I was having huge issues and have accrued over $1000 in blown sensors and ignition modules and ECU's..wiring harness guy said it was my install skills ... Its his electrical engineering skills that come into question here.

I bought the protected relays and the problems instantly went away as fuelpump relay,horn relay,power doorlocks and power windows also door poppers and trubk popper ,ecu relay,starter solenoid and fuel injectors were the issue causing the flyback through a relay block with cheap chinese relays that are unprotected by a schottky diode.

Now I am trying to save people from headaches as well as lives from being lost and I am being banned from forums like some crackpot spreading false news but its the wiring guys that sell these kits getting me banned.This is a fact and my 1st Amendment rights are being violated too. I need a Good civil rights attorney too if anyone knows one..
 

Attachments

  • IMG_20211216_232425.jpg
    IMG_20211216_232425.jpg
    57 KB · Views: 145
  • Screenshot 2021-12-16 180128.jpg
    Screenshot 2021-12-16 180128.jpg
    27.5 KB · Views: 138
  • Screenshot 2021-12-17 040835.jpg
    Screenshot 2021-12-17 040835.jpg
    36.7 KB · Views: 135
  • Screenshot 2021-12-17 040953.jpg
    Screenshot 2021-12-17 040953.jpg
    42.8 KB · Views: 144
  • Screenshot 2021-12-17 200034.jpg
    Screenshot 2021-12-17 200034.jpg
    77.5 KB · Views: 173
  • Screenshot 2021-12-18 135941.jpg
    Screenshot 2021-12-18 135941.jpg
    33.7 KB · Views: 167
  • Screenshot 2021-12-18 131743.jpg
    Screenshot 2021-12-18 131743.jpg
    34.7 KB · Views: 146
Engineering news on Phys.org
Heres the schematic for the relay..They double up on soma and triple up on another circuit and feed 3 with 1 relay and with a subpar 15 amp fuse too.

They say I am the guy whos creating the issues...

What does the experts say about this?
 

Attachments

  • Screenshot 2021-12-17 225949.jpg
    Screenshot 2021-12-17 225949.jpg
    33.7 KB · Views: 141
  • s-l500.jpg
    s-l500.jpg
    17.5 KB · Views: 127
  • Screenshot 2021-12-17 225524.jpg
    Screenshot 2021-12-17 225524.jpg
    38.8 KB · Views: 131
  • Screenshot 2021-12-17 225854.jpg
    Screenshot 2021-12-17 225854.jpg
    70.3 KB · Views: 153
  • Screenshot 2021-12-17 225949.jpg
    Screenshot 2021-12-17 225949.jpg
    33.7 KB · Views: 147
  • Screenshot 2021-12-18 131743.jpg
    Screenshot 2021-12-18 131743.jpg
    34.7 KB · Views: 145
What do you expect PF to do about it?

When the relay coil is close to the driver on a PCB, it is easy to place a flyback diode. But when they are far apart, the diode needs to be with the driver where the polarity is known, with a twisted pair to power the remote relay coil.
 
  • Like
Likes Averagesupernova and nsaspook
I find this rant a bit on the silly side. If someone in some industry has 'issues' that are causing so many problems in said industry, then come up with a better product. I'm not tell you to go pound sand, just realize that many times problems like these go on for years since not everyone involved is smart enough to realize why the failures are occurring. I have to assume that you are a builder of custom cars/street rods. Since you now realize what is happening, the ball is in your court. Make builds with equipment that doesn't cause the issue. Your reputation as a builder of a quality product will rise.
-
Also realize that many many automotive relays have no flyback protection. The circuit that drives them is taking the task of suppressing the spike generated by the falling field in the relay coil. A flyback diode built into a relay can be a risky thing for the amateur to be messing with since a reversal of polarity will fry the diode and may blow the output device that is driving it. Coming on here explaining about flyback as if it is a new thing is like me coming out with big news about how people get wet if they don't come in out of the rain. If you couldn't tell, I used to work in the automotive electronics industry.
 
Baluncore said:
What do you expect PF to do about it?
Exactly. This jerk newbie already had his first attempt at this thread start deleted with a similar message, and this repost of a deleted thread earns this newbie a permanent ban from PF. Thread is locked.
 
Hey guys. I have a question related to electricity and alternating current. Say an alien fictional society developed electricity, and settled on a standard like 73V AC current at 46 Hz. How would appliances be designed, and what impact would the lower frequency and voltage have on transformers, wiring, TVs, computers, LEDs, motors, and heating, assuming the laws of physics and technology are the same as on Earth?
While I was rolling out a shielded cable, a though came to my mind - what happens to the current flow in the cable if there came a short between the wire and the shield in both ends of the cable? For simplicity, lets assume a 1-wire copper wire wrapped in an aluminum shield. The wire and the shield has the same cross section area. There are insulating material between them, and in both ends there is a short between them. My first thought, the total resistance of the cable would be reduced...
I used to be an HVAC technician. One time I had a service call in which there was no power to the thermostat. The thermostat did not have power because the fuse in the air handler was blown. The fuse in the air handler was blown because there was a low voltage short. The rubber coating on one of the thermostat wires was chewed off by a rodent. The exposed metal in the thermostat wire was touching the metal cabinet of the air handler. This was a low voltage short. This low voltage...

Similar threads

Back
Top