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]> 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]> 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] 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]> 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]> 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]> 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]> 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] | http://www.packetflux.com > <http://www.linkedin.com/in/fwchristian> <http://facebook.com/packetflux> > <http://twitter.com/@packetflux> > > > > >
