I run WTM4200's off of +48VDC plants. Reach out to Ken Ruppel if you want/need more details.
On Mon, Sep 21, 2020 at 11:05 AM Steve Jones <thatoneguyst...@gmail.com> wrote: > These are wtm4200. He told me the connector in the radio bonds + to ground > at the radio. Could be wrong. I'm outside my wheelhouse anyway with this > being our first direct dc radios. > > On Mon, Sep 21, 2020, 10:00 AM Josh Baird <joshba...@gmail.com> wrote: > >> I should have said -- at least the WTM4200 and WTM4800, both of which I >> have used. >> >> On Mon, Sep 21, 2020 at 10:59 AM Josh Baird <joshba...@gmail.com> wrote: >> >>> Aviat radios don't bond + or - to the chassis. You can run them at >>> -48VDC or +48VDC. >>> >>> On Mon, Sep 21, 2020 at 10:45 AM Steve Jones <thatoneguyst...@gmail.com> >>> wrote: >>> >>>> So, like on these aviats, my contractor says they're -48v, but the >>>> connector in the radio bonds to ground. Does that mean my whole site has to >>>> have -48v or just radios powered by that particular psu? >>>> >>>> On Mon, Sep 21, 2020, 8:59 AM Ken Hohhof <af...@kwisp.com> wrote: >>>> >>>>> Now if we could get the manufacturers to be less secretive about their >>>>> POE schemes. They mostly want you to use their POE device and don’t want >>>>> to document the pinouts or explain if it matters which side is referenced >>>>> to ground. >>>>> >>>>> >>>>> >>>>> Mostly I find that using a Cat6-POE-APC with the jumpers as set at the >>>>> factory and + and – hooked up per the markings works. Which is basically >>>>> 802.3at. It works with the – side grounded, I suspect it would also work >>>>> with the + side grounded, or neither. I was hesitant to use this on a >>>>> PTP820 but it works fine. I don’t know why they make their POE scheme >>>>> sound so mysterious. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> *From:* AF <af-boun...@af.afmug.com> *On Behalf Of *Josh Baird >>>>> *Sent:* Monday, September 21, 2020 8:44 AM >>>>> *To:* AnimalFarm Microwave Users Group <af@af.afmug.com> >>>>> *Subject:* Re: [AFMUG] -48 noob questions (mikrotik) >>>>> >>>>> >>>>> >>>>> Yep - great explanation! >>>>> >>>>> >>>>> >>>>> On Sun, Sep 20, 2020 at 4:55 PM Chuck McCown <ch...@wbmfg.com> wrote: >>>>> >>>>> You have a power supply, say a 6 volt car battery. You connect a pair >>>>> of headlights to it with two wires. All is well. >>>>> >>>>> >>>>> >>>>> Now you start building cars. And you are going to wire up the >>>>> headlights. Someone points out that you can save some money on wiring by >>>>> using the car chassis instead if one of the wires. >>>>> >>>>> >>>>> >>>>> You decide to run the positive connection from the battery to the >>>>> headlights with wire and return the current via the car’s chassis. >>>>> >>>>> >>>>> >>>>> Now you have turned a 6 volt electrical system into a +6 volt system. >>>>> If you reverse the battery and connect the + side to the chassis and run >>>>> the wire from the negative post to the headlights , it will still work >>>>> fine. The headlights don’t care. Now you have a -6 volt electrical >>>>> system. >>>>> >>>>> >>>>> >>>>> The headlights don’t care but the radio does. Most radios expect the >>>>> chassis to be negative and their power wire to be positive. You can >>>>> “float” the radio by mounting it on an insulator and connecting its power >>>>> wire to the car’s chases and the chassis of the radio to the negative wire >>>>> going to the battery. A bit dangerous but I have had to do this at times. >>>>> >>>>> >>>>> >>>>> Oh, and the car is an early VW. >>>>> >>>>> Sent from my iPhone >>>>> >>>>> >>>>> >>>>> On Sep 20, 2020, at 2:19 PM, Steve Jones <thatoneguyst...@gmail.com> >>>>> wrote: >>>>> >>>>> >>>>> >>>>> I still cant comprehend any of this. I'm just dumb when it comes to it >>>>> >>>>> >>>>> >>>>> On Sat, Sep 19, 2020, 2:51 PM <ch...@wbmfg.com> wrote: >>>>> >>>>> Yes. >>>>> >>>>> >>>>> >>>>> *From:* TJ Trout >>>>> >>>>> *Sent:* Saturday, September 19, 2020 1:48 PM >>>>> >>>>> *To:* AnimalFarm Microwave Users Group >>>>> >>>>> *Subject:* Re: [AFMUG] -48 noob questions (mikrotik) >>>>> >>>>> >>>>> >>>>> It's just a simple 48 to 12v converter to feed the mikrotik. I tested >>>>> with a ict +48 supply and the 12v comes out fine, I'm 99% sure it will >>>>> work >>>>> on the wood bench, and about 90% sure it will work in a rack. >>>>> >>>>> >>>>> >>>>> If it was true -48 I would assume the + terminal would be bonded with >>>>> chassis ground? >>>>> >>>>> >>>>> >>>>> On Sat, Sep 19, 2020, 12:45 PM TJ Trout <t...@voltbb.com> wrote: >>>>> >>>>> I think some of my devices have the chassis ground bonded with the >>>>> negative input terminals, I discovered this >>>>> because I am running a telecom rectifier shelf designed for -48 on a >>>>> +48 system because it's floating, but this >>>>> causes the + output to not be fused, so I practiced arc welding once. >>>>> >>>>> Strange, didn't know the 1100 had dc input, but it looks floating >>>>> though (per specs -48, 12-57 V) >>>>> >>>>> >>>>> >>>>> >>>>> On Sat, Sep 19, 2020 at 12:40 PM <ch...@wbmfg.com> wrote: >>>>> >>>>> I don’t think I have ever seen a true +48 load. >>>>> >>>>> >>>>> >>>>> *From:* Ken Hohhof >>>>> >>>>> *Sent:* Saturday, September 19, 2020 1:29 PM >>>>> >>>>> *To:* 'AnimalFarm Microwave Users Group' >>>>> >>>>> *Subject:* Re: [AFMUG] -48 noob questions (mikrotik) >>>>> >>>>> >>>>> >>>>> Different situation, but I have several sites with 1100ahx4 powered >>>>> with +48, even though Mikrotik says they take -48. I suspect you will >>>>> find >>>>> the same to be true on the CCR. >>>>> >>>>> >>>>> >>>>> Connect the – terminal to ground and the + terminal to +48, obviously >>>>> you don’t want to apply reverse polarity by trying to connect +48 to the >>>>> -48 terminal. >>>>> >>>>> >>>>> >>>>> I have some ccr1009 and ccr1036 but they are all AC powered, and I >>>>> have no ccr1072, so I can’t answer your exact question. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> *From:* AF <af-boun...@af.afmug.com> *On Behalf Of *TJ Trout >>>>> *Sent:* Saturday, September 19, 2020 2:19 PM >>>>> *To:* AnimalFarm Microwave Users Group <af@af.afmug.com> >>>>> *Subject:* [AFMUG] -48 noob questions (mikrotik) >>>>> >>>>> >>>>> >>>>> So I have a handful of ccr1072's that I want to run on our +48v plant, >>>>> mikrotik sells a '-48v telecom' power supply and they insist it's not >>>>> compatible with +48v. I ordered one for testing and both +/- input >>>>> terminals have no reference to chassis ground. I went ahead and applied >>>>> +48v and the power supply fired up (no smoke) and when measuring from >>>>> chassis ground to the input terminals I see no difference in potential. >>>>> >>>>> >>>>> >>>>> Before I shove this into a $3,000 router I wanted to see what I may be >>>>> missing here? >>>>> ------------------------------ >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> ------------------------------ >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>>> -- >>>>> AF mailing list >>>>> AF@af.afmug.com >>>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>>> >>>> -- >>>> AF mailing list >>>> AF@af.afmug.com >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> > -- > AF mailing list > AF@af.afmug.com > http://af.afmug.com/mailman/listinfo/af_af.afmug.com >
-- AF mailing list AF@af.afmug.com http://af.afmug.com/mailman/listinfo/af_af.afmug.com
