Will a PWM controller cause noise on analog cctv camera?

ms334
ms334 Registered Users Posts: 10 ✭✭
I'm planning on powering an analog cctv camera with a solar panel. Do you think a PWM controller would cause noise in the video picture?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    Welcome to the forum.

    What you mean is power it from a battery recharged by a solar panel through a PWM controller.

    There's a good probability that there will be some noise caused by the charge controller. How much and when is debatable, as there are several factors at work here: the frequencies used by the equipment powered and the frequencies generated by the controller (which will vary as it does its job) as well as how good a job of suppressing those frequencies the particular controller is. BTW, MPPT type controllers regulate Voltage in the same manner (switching connection on/off at varying rate) so there's probably not an advantage there although some of them may have better RFI suppression.

    I'm not an RF guy, so hopefully someone who is will have a more helpful explanation.

    We have a whole thread here on the complexities of RFI as it pertains to PV systems: http://forum.solar-electric.com/showthread.php?5887-Radio-Noise-from-PV-System
  • ms334
    ms334 Registered Users Posts: 10 ✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    Ok, I guess I'll just have to try it and see. I guess I'll buy the best controller I can find. The Morninstar SS-6L-12V looks pretty good. I'll post some pics of my system once it's all set up.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Will a PWM controller cause noise on analog cctv camera?

    Much of the new Audio/Video equipment is done with various Digital Data Links. In general, you will have little interference if you can stick with digital signaling.

    However, it is possible to have an "electrically noisy" Radio Frequency source (noisy inverter, MPPT charge controller, etc.) that can interfere with over the air digital--Usually that means that the system works or not (i.e., you get good range with your digital RF signals, or simply nothing).

    For over the air signalling, you will see 500' range listed, but find that it has problems going 50' from one side of the home to the other. Plus many devices use "unlicenced" frequencies--Same ones that microwaves, cordless phones, etc. use--So you can have interference among these various devices too.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • HandyBob
    HandyBob Banned Posts: 31
    Re: Will a PWM controller cause noise on analog cctv camera?

    I am not an electronics wizard, but I did an RV system for a HAM friend, using a Morningstar Tristar PWM. He told me he was shocked to find no RFI problems at all. My opinion would be to go bigger than a SunSaver. Those are too basic and small to do all things well.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    you don't have to go bigger. the problem is most likely to occur in the baseband of the video signal being from near dc to 4.5mhz. putting that video through coaxial cable such as rg 59 should prevent it getting in that way. be sure connections are good and solid to prevent rectification which can lead to problems. it is still possible for it to feed into the camera via the dc lines, but this is rare and you can cross that bridge if it happens.
  • ms334
    ms334 Registered Users Posts: 10 ✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    Hi guys I finished it a couple weeks ago. It's working fine and there isn't any noise in the picture from the charge controller.
    Attachment not found.Attachment not found.Attachment not found.Attachment not found.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    Cool. Is this for monitoring game trails or to look at the snow on your PV panel? does it broadcast?
    What other equipment did you use? Total cost and can you describe the setup and what is in the garbage can , etc?

    cheers
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • 2manytoyz
    2manytoyz Solar Expert Posts: 373 ✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    I've noticed my charge controller starts a PWM buzz during the peak of the day. I could see the noise on a CCTV camera at my last house, but the video cable was close to the solar panel feed lines. I used a couple of ferrites to reduce the noise, and they produced an audible noise when the two halves were put together:

    [video=youtube_share;ffXBcXPQ9gc]http://youtu.be/ffXBcXPQ9gc[/video]

    Ultimately, moving the video cable solved the RF issue. No issues with noise on the 12VDC power.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    robert
    that's an appreciable amount on the wires, much more than i would've ever expected to make the ferrites buzz like that. i am assuming you put the ferrites on the controller leads, but did you try putting the ferrites on the outside of the cctv leads?
  • 2manytoyz
    2manytoyz Solar Expert Posts: 373 ✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    I'd never seen anything that bad before, which is why I ended up video recording the phenomenon. I do put smaller ferrites on the video cables where they connect to the CCTV DVR.

    I've since moved to another house, and the layout is different. The camera lines are some distance from the solar setup. But during the peak of the day, I can now hear the same frequency buzzing on the 4/0 power cable feeding one of my inverters. If I put my hand on the power connection on the back of the inverter, it will dampen it significantly. It's enough of a hum that the wife has asked what it was.

    Doesn't appear to hurt anything. My battery bank is happy, and all the electronics are happy now the cameras aren't so close. It's been doing this for 7 years!
  • ms334
    ms334 Registered Users Posts: 10 ✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?
    westbranch wrote: »
    Cool. Is this for monitoring game trails or to look at the snow on your PV panel? does it broadcast?
    What other equipment did you use? Total cost and can you describe the setup and what is in the garbage can , etc?

    cheers

    This was on the far side of our property where we rarely go, so I thought it would be cool to see what happens there. I can log in over the internet and see what's happening any time. I wasn't going to point it at the solar panel, but then I thought I may as well include that in the picture to see how it was doing. Originally I was going to have a tilt mechanism to empty the snow off it, but the snow actually melts on it's own really well. I guess since the panel is black helps. Actually when the snow was frozen on the panel, I tried turning it upside down and the snow stuck to it, so having a tilt mechanism would of done nothing anyways.

    I thought about wireless but wasn't sure how reliable it would be going through so many trees, so I ran a 3000ft cat5 cable to the house.

    The charge controller I found actually put out 15v so I was worried about the camera being damaged, so I put 500ft of cat5 in between the camera and CC to bring the voltage down to about 13v. I put the wire in the garbage can to keep any animals from chewing on it, etc..

    Here's a breakdown of the costs

    470.25 (3) 1000ft CAT5e Outdoor Direct Burial & UV Rated Ethernet Network Cable 350 MHz
    129.00 EverFocus Ultra Series Super Low Light Box Camera (Black) (12v 160ma power requirement)
    39.95 MG Electronics CAMH-800K 15" Indoor/Outdoor Aluminum Camera Housing with Heater/Blower & Bracket
    125.99 100W Watt Monocrystalline Solar Panel, Windy Nation brand
    39.95 1CH CCTV Video Signal Booster Amplifier transmission upto 3000F (12v 100ma power requirement)
    206.09 DEKA SOLAR 63AH Sealed 12V AGM Battery for PV, Solar & Wind POWER - MADE in USA
    44.99 Morningstar SunSaver SS-6L-12V SOLAR CONTROLLER

    Total about $1050, but I spent a lot more on tools, gas, etc, so it was probably a few hundred more than that.

    Right now the camera is really reliable, but the cable is buried in snow. I'm hoping when it melts animals don't start stepping on it etc. I might get some pvc pipe and put it inside that, or go wireless. Then I could put an HD camera up I guess..
  • ms334
    ms334 Registered Users Posts: 10 ✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    Also, the camera uses 180ma and the amplifier 100ma. I don't have any IR illuminators because they would of used way too much power. The camera is so light sensitive though that you can see a lot if the moon is out. This isn't the best picture, it gets brighter than this with a full moon. Attachment not found.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Will a PWM controller cause noise on analog cctv camera?

    MS, tell us more about those batteries, if you have the info, you may be able to adjust the Voltage setting a bit higher, it is a bit low I think... Do you now if they are Lithium type batteries?
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada