EMI / RFI and setting timing = problems - Page 3

art leong · 09-09-2014, 10:09 AM

You remarked about everything being grounded etc. If you ground the shielded cable pickup wires, you just created a magnetic for EMI problems.
I did this, so I learned from experience.

buzzinhalfdozen · 09-09-2014, 10:37 AM

Art, you are correct any shield should only be grounded on one end, by grounding both ends you're making an antenna.

joespanova · 09-09-2014, 11:15 AM

OK
So what the heck is the ground for?

joespanova · 09-09-2014, 11:17 AM

Quote:

Originally Posted by buzzinhalfdozen

btw you actually will only have 1 lite that works on your race car!

True LOL

buzzinhalfdozen · 09-10-2014, 08:05 AM

Joe the ground is for the shield, it should only be connected at 1 end to ground.

joespanova · 09-10-2014, 08:32 AM

Quote:

Originally Posted by buzzinhalfdozen

Joe the ground is for the shield, it should only be connected at 1 end to ground.

I dont follow..there's one pigtail.........how could you connect it at both ends?

buzzinhalfdozen · 09-10-2014, 09:59 AM

Art had commented about grounding shields, yes this harness has only 1 lug end but others have exposed wires or cable that some people connect to ground. By connecting both ends of a shield to ground you can actually induce EMI issues. If you have connected the lug on that cable to ground then that is correct. Most older MSD systems would work perfectly with an unshielded crank trigger jumper or pickup when they introduced the digital systems unshielded wiring caused lots of problems.As I stated earlier, the switch from analog to digital systems opened up a lot of issues for quite a few racers.

joespanova · 09-10-2014, 11:44 AM

Quote:

Originally Posted by buzzinhalfdozen

As I stated earlier, the switch from analog to digital systems opened up a lot of issues for quite a few racers.

Yeah . Me being one of them

Bill Edgeworth · 09-10-2014, 12:10 PM

Just something everyone should know about timing lights;
The inductive pick up in most utilize ferrite. This is a magnetic ceramic material used to make the nest that the wire fits in in the pick up.
Ferrite is a very fragile material and if it cracks the performance of the pick up will be compromised.
better timing lights usually have the core encapsulated to help prevent this but I have a $400 Snap-On one that I once cracked the core trying to fit it on some real fat wires.

So what you think is noise could be a timing light problem.

09-09-2014, 10:09 AM	#21
art leong VIP Member Join Date: Dec 2001 Location: Richmond Hill, Georgia Posts: 2,003 Likes: 0 Liked 1 Time in 1 Post	Re: EMI / RFI and setting timing = problems You remarked about everything being grounded etc. If you ground the shielded cable pickup wires, you just created a magnetic for EMI problems. I did this, so I learned from experience. __________________ Art Leong 2095 SS

09-09-2014, 10:37 AM	#22
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: EMI / RFI and setting timing = problems Art, you are correct any shield should only be grounded on one end, by grounding both ends you're making an antenna. __________________ Joe Buchanan SS/BX 3117

09-09-2014, 11:15 AM	#23
joespanova Senior Member Join Date: Jun 2011 Location: Ga. Posts: 521 Likes: 7 Liked 13 Times in 11 Posts	Re: EMI / RFI and setting timing = problems OK So what the heck is the ground for?

09-10-2014, 08:05 AM	#25
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: EMI / RFI and setting timing = problems Joe the ground is for the shield, it should only be connected at 1 end to ground. __________________ Joe Buchanan SS/BX 3117

09-10-2014, 09:59 AM	#27
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: EMI / RFI and setting timing = problems Art had commented about grounding shields, yes this harness has only 1 lug end but others have exposed wires or cable that some people connect to ground. By connecting both ends of a shield to ground you can actually induce EMI issues. If you have connected the lug on that cable to ground then that is correct. Most older MSD systems would work perfectly with an unshielded crank trigger jumper or pickup when they introduced the digital systems unshielded wiring caused lots of problems.As I stated earlier, the switch from analog to digital systems opened up a lot of issues for quite a few racers. __________________ Joe Buchanan SS/BX 3117

09-10-2014, 12:10 PM	#29
Bill Edgeworth Member Join Date: Oct 2006 Location: Tacoma, WA Posts: 258 Likes: 0 Liked 0 Times in 0 Posts	Re: EMI / RFI and setting timing = problems Just something everyone should know about timing lights; The inductive pick up in most utilize ferrite. This is a magnetic ceramic material used to make the nest that the wire fits in in the pick up. Ferrite is a very fragile material and if it cracks the performance of the pick up will be compromised. better timing lights usually have the core encapsulated to help prevent this but I have a $400 Snap-On one that I once cracked the core trying to fit it on some real fat wires. So what you think is noise could be a timing light problem. __________________ Bill Edgeworth 6471 STK