600SSH I think is the newest. On Friday, February 19, 2016, Adam Moffett <[email protected]> wrote:
> The latest model is 200SSH. These were bought new (or allegedly new) > within the past few months. > They haven't discontinued it have they? > > On 2/19/2016 3:42 PM, Sean Heskett wrote: > > Isn't the 200SS about 10 years old. > > I'd replace it with something newer > > > > On Friday, February 19, 2016, Adam Moffett < > <javascript:_e(%7B%7D,'cvml','[email protected]');>[email protected] > <javascript:_e(%7B%7D,'cvml','[email protected]');>> wrote: > >> I would have assumed they weren't supposed to short the + and - wires >> when clamped. That would be the opposite of protection lol. I also don't >> get why the short to stay there with the power shut off. I spent a good >> 15-20 minutes checking things with the power shut off, and the short didn't >> go away until I disconnected and reconnected wires on the SS. I would have >> guessed the clamping would stop when the over current or over voltage >> condition went away. >> >> I did eventually find literature saying that the 200SS can take up to >> 6.5amps. This BS uses 90 watts on bootup, and maybe 60 watts in normal >> operation. The spec sheet says 125 Watt max. So somewhere from 1.5 to 2.5 >> amps. >> >> Maybe that particular SS is just broken in some way? If so, it's a >> dangerous mode of failure. >> >> On 2/19/2016 2:30 PM, George Skorup wrote: >> >>> Definitely sounds like the SS was clamping. Maybe the SS thought a surge >>> occurred at initial startup of the power supply? And FYI, I have used Traco >>> TSP 48v supplies with -48 radios just fine, output is floating. >>> >>> On 2/19/2016 10:40 AM, Adam Moffett wrote: >>> >>>> ...my first thought of course was maybe it was hooked up wrong the >>>> first time. The four 16ga wires hold their shape pretty well and I didn't >>>> have to re-bend them to fit, so I'm pretty sure they were on there >>>> correctly. >>>> >>>> People talk about SS's "clamping" or "clamping to ground". Could that >>>> cause a short? I never tested the power wires against ground. >>>> >>>> If you're thinking +48 and -48 mixed on the tower, there are only two >>>> devices on the tower right now. One base station and one backhaul, and >>>> they're both -48. There's some 24v stuff in the enclosure at the bottom >>>> (switch, site monitor), but none of those have a ground referenced to power >>>> and they're isolated from the other stuff by a 48v to 24v converter. >>>> >>>> >>>> On 2/19/2016 11:27 AM, Adam Moffett wrote: >>>> >>>>> So I went out to a new location yesterday afternoon just to turn the >>>>> breakers on. The power co had just plugged in the meter a few days prior. >>>>> >>>>> The Traco 48v power supply there immediately went into an alarm >>>>> state. After some troubleshooting I found a dead short on the -48v power >>>>> bus (terminal blocks with jumpers actually). The short ended up being on >>>>> the power cable to a Wimax base station, I read 0 ohms between + and - on >>>>> that cable. >>>>> >>>>> There's a Motorola 200SS surge suppressor within 5' of the power bus, >>>>> and then about 80' of wire to the base station. I checked resistance >>>>> between + and - on each side of the SS and read 0 ohms both ways. There >>>>> are actually 4x 16ga wires going to the top, so two were screwed down to + >>>>> on the load side of the SS and two on the - side. >>>>> >>>>> That whole part was backstory. This is where the mystery starts. >>>>> >>>>> I pulled all 4 wires off the load side of the SS to see if I could >>>>> narrow down which pair was shorted, and I couldn't find a short. I checked >>>>> the load side and the supply side of the SS and it was open on both sides. >>>>> So then I reconnected the wires to the SS and checked again - no short. I >>>>> plugged the BTS back into the bus...powered up just fine. >>>>> >>>>> So where did the short circuit come from and where did it go? In >>>>> hindsight it seems like it had to be in the SS or before it. If it was >>>>> shorted at the top there would have been > 0 ohms of resistance with the >>>>> 80' of wire. >>>>> >>>>> >>>>> >>>> >>> >> >
