eHam

eHam Forums => RFI / EMI => Topic started by: AB3TH on August 29, 2016, 03:33:35 AM



Title: Magnetic ballasts and shop lighting rework
Post by: AB3TH on August 29, 2016, 03:33:35 AM
Last week I suddenly started to get S9 RFI across every band, DC to UHF.  It was just after a storm and I thought maybe a ground problem but tracked it to my shop lighting.  There's a bad ballast (or several) in there.  Got six fixtures, a dozen ballasts and 24 tubes all together.  The thing is that I just replaced most of the ballasts last year.  I had a power surge that blew out most of my lights (and a lot of other stuff) and replaced most ballasts with Robertson electronic ballasts.  It wasn't fun or cheap.  Fixtures are in a finished drywall ceiling and it's hard to get a ladder under most fixtures.  Some of the new ballasts were flakey after only a couple months.  Flickering and hard starting.  Obviously one or more now have serious problems.

So, what to do?  I doubt ferrites are a good solution. At least some ballasts must be replaced immediately.  I have a few new-old-stock genuine magnetic ballasts, not electronic, but only enough for a few fixtures.  I'm fairly sure that all my replaced ballasts are going to die.  I bought what I thought were good supposedly american-made electronic ballasts.  Obviously Robertson ballasts are trash.  I really don't want to spend upwards of $1K for new LED fixtures, assuming that I can even find reliable and low-RFI units.  New ballasts for my existing fluorescent fixtures are not cheap and I'm very reluctant to use electronic ballasts now.  Finding enough old-style magnetic ballasts will be hard.  I expect shop lighting to last indefinitely, not die every year.

If I do put up some LED replacements, what brand??  Any suggestions?



Title: RE: Magnetic ballasts and shop lighting rework
Post by: AA4PB on August 29, 2016, 07:12:19 AM
I haven't used any but I see that there are replacement LED tubes for the existing fixtures. One type uses the existing ballast. The other type has you remove the ballast and rewire directly to the bulb sockets. They are not cheap - but if you only have to replace them every 5-10 years it might be worthwhile.



Title: RE: Magnetic ballasts and shop lighting rework
Post by: AB3TH on August 29, 2016, 07:43:31 AM
There is stuff in the way under almost every fixture.  I have to move machinery or put scaffolding for access.  No access from above.  It's a forest of trusses and insulation with no walk boards and about 2 feet headroom.   I already did this once and do not want to do it again.  Can't use something that uses existing ballasts since they're not trustworthy.  If I go to the effort it needs to be good stuff.  Only other options are leave the lights off (bad) or hang new ones underneath somehow (bad and ugly).  Was just hoping somebody smarter had a better idea.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: WB4SPT on August 29, 2016, 11:57:23 AM
I'm about done with fluorescents too. 
I only have one of these as a test, so far so good:

http://www.lowes.com/pd/Metalux-SLWP-LED-Series-Wrap-Shop-Light-Common-4-ft-Actual-5-512-in-x-48-6-in/1000018099


Title: RE: Magnetic ballasts and shop lighting rework
Post by: AA4PB on August 29, 2016, 02:42:25 PM
With most shop lights if you remove the florescent tubes you can then remove the cover that is covering the wiring and ballasts. If you get the non-ballast type of LED tubes just follow the supplied directions to disconnect the ballast and re-route the power directly to the LED tubes. It amounts to simply cutting wires from the ballast and connecting the appropriate wires with wire nuts. I saw the LED tubes at Home Depot.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: WA2ISE on August 30, 2016, 07:44:30 AM
... I had a power surge that blew out most of my lights (and a lot of other stuff) and replaced most ballasts

Maybe you have a bad neutral connection in your house, maybe in the circuit breaker panel.  That can create "power surges". 


Title: RE: Magnetic ballasts and shop lighting rework
Post by: N4MQ on August 30, 2016, 09:01:56 AM
I went to Costco and have all led lights - less power and cold wx operation - $35 for each assembly and no more bulbs...N4MQ woody ::)


Title: RE: Magnetic ballasts and shop lighting rework
Post by: SWMAN on August 31, 2016, 07:26:41 AM
 I have tried 2 of those LED 4 foot tubes in a garage fixture. They are made by Phillips and is the type were you use the already existing ballast, sort of a plug and play lamp. My RFI was so bad that I removed them and put the old lamps back in. I listen to AM radio a lot for news, it totally overwhelmed my hearing of the station. On 80 and 40 it was even worse. I'm not sure if other brands would be better as I did not try them. The old florescent tubes are totally quiet on all bands.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: KD0REQ on August 31, 2016, 03:16:55 PM
Costco a year ago had Feit LED replacement 4-footers that reportedly were bad jammers, too.  moral is, try a pair.  if they blow you out of your op position, take them back, and tell the clerk they are illegal because they violate FCC noise regulations.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: AB3TH on August 31, 2016, 03:43:36 PM
I bought a few LED replacement tubes to try.  They got a lot cheaper since the last time I looked.  I'm not real confident that they'll be great or reliable but I got some.  I also got lots of split-core ferrites and I'll check a couple on the bench with and without ferrites to see how good they are.  I'm fairly sure that it's a bad idea to try running with the existing ballasts.  Some LEDs are designed to tolerate that but you lose efficiency and still have the noise of an electronic ballast.  So, if the ones I bought are OK on the bench I'll start pulling ballasts and installing.  That will probably take me a month.  Too much junk in the way.  I didn't get Phillips.

The original surge that blew lots of stuff was power company.  Storm knocked a 14KV line across the local 220 feeder.  Blew out my whole-house surge protector, a dozen outlet strips, appliances, etc.  Power company would not pay because it was an "act of God".  Power was out for 3 days.  It took out every light that was turned on. 


Title: RE: Magnetic ballasts and shop lighting rework
Post by: AA4HA on September 02, 2016, 02:10:31 PM
The only way you are going to totally get rid of the RFI is to pull out the ballasts and go with a true DC voltage system. Those replacements where you pop in LED bulbs to AC fixtures use tiny DC/DC converters to knock the line voltage down to something that the LED bulb can handle (low voltage DC). Each one of those DC/DC converters is a tiny noise generator and they wabble and warble all up and down the spectrum. You will hear harmonics well up in to the VHF band.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: WA8ZTZ on September 03, 2016, 03:31:33 AM
Incandescent. 


Title: RE: Magnetic ballasts and shop lighting rework
Post by: KD0REQ on September 06, 2016, 08:58:40 AM
what's wrong with bringing home a few more magnetic ballasts?

other than cold weather, where you have to spend up to $120 to get 20 or 30 below units.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: AB3TH on September 06, 2016, 09:35:41 AM
It used to be fluorescent tubes would last a long time.  All the new low-mercury tubes seem to die in 2 years and nobody in my area will accept them anymore.  Have to wait for a once-a-year hazmat day at the dump.  All the electronic ballasts I had were very noisy.  They came with the house.  I want to do something once and have it stay done for a while.  I bought a couple dozen Hyperikon LED tubes.  Put ferrites in each fixture.  RFI is down.  Noise level is down to S2 all across HF which is a lot better than before.  I figure payback from power saving is only a year.  I didn't really want to spend the time and money but it was worth it.  One less thing to complain about.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: WA2ISE on September 07, 2016, 12:02:57 PM
I put a pair of LED replacements in the florescent fixture in the kitchen, no RFI issues.  Think they're Feit. 


Title: RE: Magnetic ballasts and shop lighting rework
Post by: SWMAN on September 07, 2016, 01:19:37 PM
 ISE,  were they just plug and play or did you have to replace the ballast ?


Title: RE: Magnetic ballasts and shop lighting rework
Post by: AB3TH on September 07, 2016, 02:11:19 PM
ISE,  were they just plug and play or did you have to replace the ballast ?

Feit brand doesn't need to remove the ballast.  Unless it doesn't work in which case you do need to remove the ballast.  Some brands feed both power and neutral to one end of the tube.  Some feed from opposite ends.  Power and neutral on one end, always have to rewire.  Power on opposite ends you can generally keep the ballast without rewiring.   But, if the ballast is still in the circuit you lose a couple Watts and still have whatever noise the electronic ballast generates.  Better to disconnect the ballast.  Takes a couple minutes and some extra wire and wire nuts.  And sometimes strong language when you see how the last guy wired things.


Title: RE: Magnetic ballasts and shop lighting rework
Post by: WA2ISE on September 10, 2016, 01:39:23 PM
Better to disconnect the ballast.  Takes a couple minutes and some extra wire and wire nuts.  And sometimes strong language when you see how the last guy wired things.

Be sure to label the fixture near the bulbs to tell someone in the future that the ballast is not connected, and not to use florescent bulbs.