atcomsystems.ca/forum Forums Other TDM Phone Systems Sprint - Tadiran Telephones & Systems Tadiran APS-SL Power supply

Hello, I've noticed a problem in the past 8 months some of our APS-SL's. I've replaced 4 in different locations on our network. (We have about 70 SL sites approx.- never bothered counting them) I've asked locally but I've been told that there is no particular problem with the SL power supply. Some failed after powering off and on the system but others have just failed by themselves. Most of these systems are 6 yrs old now and have been trouble free since installation. We've been told that the IPX 500 is the replacement but SL spares will be available if required. Just wondering if anyone has had similar problems with this piece of kit. I'm trying to plan spare requirements for the SL for the future for my department as I expect these systems will be in service for some years to come. Thanks for your time.

I have seen power supplies go on most any system that is over about 5 years, including the SL. I would plan on this happening more often as you r systems age. If I were you I would keep a few spare power supplies around just in case.

Steve

Thanks Steve. I've been told that there may be a problem with the start up circuitry of some of these APS- SL's. It seems after being in service for a period of a few years if they suffer an external power failure they may not come back when power is restored. They require someone to physically switch them off and on a few times. (this can be a problem if the nearest pair of hand is 50 miles away) However that is not official and I would like to verify or dismiss it if possible. We have a lot of Sl's out there and with Tadiran supporting spares production only from 2007 onwards, my fear is they will not be so readily available. Thanks again for your time Steve...63.

We have Power Problems with the AP-SL's all the time. The bad thing is that we dont have enought of them to changed out when the ones in the field stop working. I think Tadiran is using a different company now for the power supplies. I hope these are better ones.

There was a bad lot...you may want to check.

Hello All. Thank you Texas and Coral Tech for your input. Most of my APS-Sl's are of the same vintage so I will dig a little deeper and see if there is something I need to plan for. Regards..63.

We never hae issues with the power supplies. We also have battery packs in about every SL we have ever sold.

What rev are they? I believe rev A and rev B had a recall on them. No longer Warrantied

Hello All, sorry for the delay in coming back to you. The APSL's that we've had trouble with are "Rev. 4C" Most of these P.S.U's also have a mod that appears to be post production. It's an earth wire that connects one of the PCB pillars to the DC back panel connector. (when I mentioned vintage in an earlier posting it was this mod that I was referring to. Its not on later APSL's.) I'm not really concerned with warranties, as they have been in use for about 5 years at this stage. Its just to know if I need to plan for something. Thanks for your time. Regards, 63.

Siemens had a similar problem with power supplies doing this, the problem is aging capacitors, I have a source in California for repair at about $350 each. I wish I could figure out the bad caps and just replace myself. The other option is replacing all caps but just finding them is a real problem.

Thank you Avidcomm. It looks like you nailed it. The local vendor has informed me that they had the issue diagnosed by a local agency and it seems that some of the electrolythics are drying out and preventing the PSU from restarting. I'm now upto 8 failures this year. Two came back after about an hour when removed them from their system. I've asked for more specific information (ie which ones) If they tell me I'll mail you directly. Tadiran have nothing to say on the issue. Thank you all for your input.

Regards, 63.

I have had such problem with two six-years old APSsl. I received informal help from Tadiran tech support - they suggested to change capacitor 211 on APSsl board. It is originally 25V 100mF, and have to be replaced with high ripple current, low E.S.R and long life capacitor, which value should be 150°C, 100mF, 35V, 20% (Nippon Chemi-Con - capacitor LXJ-35VB120MH12, Jamicon - capacitor WGR101M1VF, Nichikon - capacitor PL-1V101MPH).
By the way, Tadiran have good specialists - tech support gave me fast, clear and correct answer - I have changed those capacitors and now everything is good

Hello Muter. I'll source some caps and give it a go next time. I agree by the way that Tadiran have some fantastic engineers. Technically excellent and rightly proud of their product. Those that I've worked with were certainly top drawer in their field. However my vendor insists there is no problem with APSL's that Tadiran is aware of. I hope this may save you some cash too Avidcomm if you are reading. Thank you again everybody for your time and help on this issue. Regards 63.

The problem with the Tadiran APSL is the Capacitor C211 (100 micro farad). It fails because it is under rated at 25 volts. The capacitor needs to be replaced with a 50 volt capacitor. Observe polarity - the minus side of the CAP goes toward the card connector. Make sure you flow a little solder onto the connections as you heat them. There is a lot of copper to heat up before the jounts are evacuated. Heat the joints sufficiently as you resolder the cap.