That is the exact behaviour we saw.
> On 11 May 2017, at 21:59, Bill Prince <[email protected]> wrote: > > To be 100% clear.... > > The negative sides (-) are common > > The positive sides (+) are independent. > > So we should be able to put different (+) voltages on PWR1 and PWR2, and we > should not expect them to back feed each other. > > The behavior we were seeing was voltage from PWR2 was back-feeding through > PWR1 and providing power to equipment that was on PWR1, even though the > breaker to PWR1 was turned off. > bp > <part15sbs{at}gmail{dot}com> > > On 5/10/2017 4:27 PM, Forrest Christian (List Account) wrote: >> On the base unit, the - side of both DC inputs are tied together. It is >> designed that way, since it was designed to be powered from two positive >> sources. >> >> If you are connecting two -48VDC busses to the base unit by connecting >> 'common or return' to the + input on each, and the -48VDC bus to the - input >> on each, the base unit will internally connect both of those buses. As I >> described, this is by design because the unit was designed for + voltages, >> not negative ones. >> >> The next iteration of the base unit will handle this much more gracefully. >> I am not yet sure about whether the device will simply just support either >> +48VDC or -48VDC, or if you'll have to select it in some way (at ordering, >> with a jumper, etc....) >> >> >> >> On May 10, 2017 7:34 AM, "Sorin Esanu" <[email protected] >> <mailto:[email protected]>> wrote: >> Yes, neg48 plant. >> I’ll send the requested info. >> >> Thank you! >> >> >>> On 10 May 2017, at 16:32, Forrest Christian (List Account) >>> <[email protected] <mailto:[email protected]>> wrote: >>> >>> If we're still selling the same version of a product, we warranty it. We >>> regularly replace things which are far older. I like to see the in field >>> failures so I can roll the lessons learned into the next generation of >>> products. >>> >>> Just send an email info [email protected] >>> <mailto:[email protected]> with the serial (mac address) and your >>> address we'll send a ups label to ship it back to us. Please include a >>> note as to what is wrong so I can remember when I look at it. >>> >>> Oh, one thing I just noticed. .. is this a positive ground plant by >>> chance? (I.E. -48) >>> >>> >>> On May 10, 2017 7:16 AM, "Sorin Esanu" <[email protected] >>> <mailto:[email protected]>> wrote: >>> We’re monitoring A and B of our DC power plant. It is wired directly into >>> the GMT fuses panel, A and B sides. >>> This particular unit was installed over 1 year ago, close to 2 years. If >>> your offer is still valid, let me know the procedure. >>> >>> Thanks! >>> >>>> On 10 May 2017, at 10:32, Forrest Christian (List Account) >>>> <[email protected] <mailto:[email protected]>> wrote: >>>> >>>> Can you let me know more about your setup? >>>> >>>> Is this the unit you bought in November? (In case this is something which >>>> has gone weird with a batch, and somehow not caught by our test >>>> procedures). >>>> >>>> If you've got a defective one, we'll swap it, paying shipping both ways. >>>> >>>> On Tue, May 9, 2017 at 9:49 PM, Sorin Esanu <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> We’ve experienced this exact same behaviour last week. It seems like PWR1 >>>> and PWR2 are acting like one now. >>>> We are in process of replacing all the SiteMonitor II devices with Tycon >>>> TPDIN-Monitor-WEB2, which can monitor more things and it’s a lot smarter. >>>> >>>> >>>> > On 10 May 2017, at 01:31, Bill Prince <[email protected] >>>> > <mailto:[email protected]>> wrote: >>>> > >>>> > I think I have a SiteMonitor II with a problem, as I always thought that >>>> > the two power sensors (PWR1 and PWR2) were independent of each other, >>>> > and should have a pretty high impedance between then. >>>> > >>>> > We set up a new solar site, and put our load on PWR1 and the batteries >>>> > on PWR2. As soon as we hook up either one of the sense wires, the >>>> > breaker to the batteries (30 amp) pops, and all the lights go out. >>>> > >>>> > We can monitor one voltage on PWR1, or the same or different voltage on >>>> > PWR2. However, if both are connected we blow the 30 amp breaker to the >>>> > batteries. >>>> > >>>> > We've checked the polarity (both voltages are negative ground), and they >>>> > are both "about" the same voltage (although we have monitored radically >>>> > different voltage in the past (like 12V on one and 48V on the other). >>>> > This is a 48VDC system, so we are seeing ~~ 56V on both right now, >>>> > >>>> > BTW, when we hook up just one of the sensors and leave the other open, >>>> > we see ~~ 43 volts between PWR1 and PWR2. I haven't checked other >>>> > SiteMonitors, but this doesn't seem right to me. >>>> > >>>> > >>>> > -- >>>> > -- >>>> > bp >>>> > part15sbs{at}gmail{dot}com >>>> >>>> >>>> >>>> >>>> -- >>>> Forrest Christian CEO, PacketFlux Technologies, Inc. >>>> Tel: 406-449-3345 <> | Address: 3577 Countryside Road, Helena, MT 59602 >>>> [email protected] <mailto:[email protected]> | http://www.packetflux.com >>>> <http://www.packetflux.com/> >>>> <http://www.linkedin.com/in/fwchristian> >>>> <http://facebook.com/packetflux> <http://twitter.com/@packetflux> >>>> >>> >>> >> >
