Digital Ballasts and RFI

Hi all,


I'm a pretty green noob here trying to design a grow area that I hope to soon set up. I grew 12+ years ago on a 400w hps using SOG. Anyways....back to the present. I'm starting over and am looking at some of the more 'modern' equipment.....digital ballasts. I'm probably going to pick up 1000w hps and wanted to know if digital ballasts are worth the extra money. Also, I've read in older posts that there are/were rfi issues with digitals....is this still an issue? Thanks for any input!!!

GreenToe

RFI with digital ballast were a problem a few years ago....not so much now.


as long as you buy a reliable brand and use the RFI cord it comes with...you should be fine.

i have no interference.....but oddly enough my stupid cordless phone always kills any connection!

Cool, I was hoping that this problem was resolved. The energy savings and noise reduction definitely sound like great perks! I used to have the ballast from my old 400w near where I slept.....I could always hear it.

BTW, is your phone a 2.4 ghz by chance?

I miss 900 mHz phones, with handsets large enough to be held between neck and shoulder.

Anyway, you will need a good electrical ground to eliminate RFI from a digital ballast. If you do find you have some RFI issues, and you've verified a good ground connection, you can try attaching RF chokes to the effected equipment (depending upon the frequencies of the RFI--these are intended for use by amateur radio operators.)

RFI Radio Frequency Interference chokes, filters, EMI suppression cores

Ok, thanks for the great input guys! Would I be better off then going with the old style magnetic ballast then? Save money and the possible risk/tip off from any rf interference?

Greentoe said:

Ok, thanks for the great input guys! Would I be better off then going with the old style magnetic ballast then? Save money and the possible risk/tip off from any rf interference?

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Do you have a lot of RFI sensitive equipment? FWIW, I haven't heard much complaint about this in a year or two, so the equipment may have improved. Also, I should have mentioned above that manually grounding the reflector can help too (as it is the reflector that serves as an antenna.)

I doubt RFI would be a security risk. You usually need to be intentionally radiating RF (i.e. broadcasting some kind of signal) to cause severe enough direct (over the air) RFI to disturb neigbors' appliances. Unless you live in a high-density apartment building, I would also doubt that you'd be able to cause conductive interference to neighbors over the power mains. However, this is only conjecture based on what I know about RFI as a radio operator--do you have numbers on how much RF one of these things can leak? That'd help, although I still think it would have to be a level of radiated power dangerous to be in the room with before you'd have to worry about neighbors (if we're talking about typical broadcast/electronics frequency bands.)

Will whoever you're going to buy it from permit you to exchange it if it generates too much RFI in your home? If so, I'd go ahead and try it. If not, I'd think carefully about why you need a digital ballast (heat? power consumption? longevity?) and whether it might be better to forgo it.

Ok, maybe I'm getting anxious over nothing then. I read a thread from '06 about digital ballasts and rf interference....and got a bit nervous. I own a house...neighbors are relatively close though and was just worried about messing up their electrical equipment. It sounds like lots of folks however are using digital ballasts these days without problem...

This and another thread are the only ones that touch on my friends issues. He has a 600w HPS with a digital ballast. He got a note from the cable company that they are reading a signal from inside his house. I guess the cable company can check and see if you are stealing cable somehow by driving near your house and using some sort of equipment. And the digital ballast puts off that signal. Has this happened to anyone else? These RF chokes are the only thing I've found. Anyone else have any ideas?

bryant228 said:

This and another thread are the only ones that touch on my friends issues. He has a 600w HPS with a digital ballast. He got a note from the cable company that they are reading a signal from inside his house. I guess the cable company can check and see if you are stealing cable somehow by driving near your house and using some sort of equipment. And the digital ballast puts off that signal. Has this happened to anyone else? These RF chokes are the only thing I've found. Anyone else have any ideas?

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More likely, a neighbor of 'his' called cable for a bad signal in his house. They came out and found noise on the line then traced it back you your 'buddies' But it sounds like a floating ground, and the RFI is hopping onto the cable line from that.

BigBudBalls said:

More likely, a neighbor of 'his' called cable for a bad signal in his house. They came out and found noise on the line then traced it back you your 'buddies' But it sounds like a floating ground, and the RFI is hopping onto the cable line from that.

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Thanks Big. The thing is, he has cable too and has had no problem with it. What type of ground does he need to do? Thanks for your help.

bryant228 said:

Thanks Big. The thing is, he has cable too and has had no problem with it. What type of ground does he need to do? Thanks for your help.

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Not knowing the particulars, I can't say. But I think there is a grounding issue in his place and his cable is working possible because of some isolation and where the ballast is in relation to the TV (electrically, not physically)

Try this, hook a *volt* meter between the ground pin on the ballast outlet and say a plumbing pipe (make sure its not a PEX or other plastic plumbing) And measure the AC and the DC volts. With and without the ballast on.
(an O'scope would work better, but I bet not many here own own) If you need to make extensions on the leads, be sure to zero it out prior to measuring.

BigBudBalls said:

Not knowing the particulars, I can't say. But I think there is a grounding issue in his place and his cable is working possible because of some isolation and where the ballast is in relation to the TV (electrically, not physically)

Try this, hook a *volt* meter between the ground pin on the ballast outlet and say a plumbing pipe (make sure its not a PEX or other plastic plumbing) And measure the AC and the DC volts. With and without the ballast on.
(an O'scope would work better, but I bet not many here own own) If you need to make extensions on the leads, be sure to zero it out prior to measuring.

Click to expand...

Thank you very much. He thought he pulled a fast one and had the cable company come out when the lights where off. They turned it back on and that was that. Well now they came back want to search his house for this leak! He started a new post for this problem:

https://www.rollitup.org/indoor-growing/125536-digital-ballast-rf-interference.html

Could pop in there please? YOu seem to be the only one who has a nice grip on this issue.

So, what does measureing the volts do? And is this the cord from the ballast to the light or the ballast to the wall outlet? Thanks again for your help. Rep for you!