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my SxS demo

Started by xhausted110, December 26, 2012, 10:58:59 AM

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xhausted110

so recently I decided to make a step demo, so here it is.
http://www.youtube.com/watch?v=TKjx6FApDMo







yes the contact on the bottom wiper of the connector is broken, I am getting a new connector anyway as the one I have is defective.  we have dial tone,busy, and fast busy hooked up. also an outside line is hooked up through my key system.
- Evan

AE_Collector

Havent seen a "new" SxS Demo project get underway for awhile now. Nice going. Did you just recently round up all of the material needed or have you had it for some time waiting to get at the project? Is it AE or WE equipment?

Replacement wipers must be relatively easy to locate aren't they?

Terry

xhausted110

yes, i have replacement wipers, but why replace the wiper when i am getting a whole new connector soon? it is both AE and WE.
- Evan

xhausted110

#3
update: rewired EVERYTHING! it's all going to go to a 110 block for jumpering ect.


- Evan

WesternElectricBen

Awsome, obviously I have seen your YT videos. Wink wink
Ben or RVI

marty

Hi ;
What is the size of your Power Supply ?? How much voltage and at what amperage  ??
And which and how many units do you have that your power supply is supporting ??
I would love to see your schematic..
THANK YOU Marty

DavePEI

#6
Quote from: marty on March 28, 2013, 11:52:15 PM
Hi ;
What is the size of your Power Supply ?? How much voltage and at what amperage  ??
And which and how many units do you have that your power supply is supporting ??
I would love to see your schematic..
THANK YOU Marty
Hi Marty:

A Strowger demo of two or three switches theoretically should be able to operate with a 48 volt 2 or 3 amp supply. However, with my British Strowger switch, I discovered that with a 7 amp switching supply when the switches were activating, the voltage could fall under momentary load. To solve this, I put a huge 10,000UF electrolytic cap following the supply with a bleeder resistor across it to allow it to discharge when the power is turned off.

The theory behind this is when the supply momentarily falls out of regulation due to the strong switching transients, the electrolytic will even out the voltage fast enough until the regulation of the switching supply catches up milliseconds later by storing and supplying the 48v during peak demand. It wasn't that the supply couldn't supply the peak current or voltage required, but that it couldn't regulate it fast enough when a pulse occurred. I discovered this quite by accident when I observed the waveform of the output DC on an oscilloscope.

It made a world of difference, though current-wise the supply should have produced more way more current than needed. The problem was the switching transients when the relays pulsed - the supply couldn't react fast enough to regulation-wise to keep up to the transients. Doing so made a world of difference in how the switches functioned.

I wouldn't have had this problem had I used a conventional supply - it is just because it was a switching supply (and perhaps not overly well designed)  that I had this problem. The supply I used was designed for CNC purposes, and is physically quite small, saving space on the demo frame (and cost  if I remember correctly was about $45.00 to buy).

On my North American Strowger switch, I use a physically much larger 10 amp switching supply. Presumably it is better designed, as I never had this problem with it.

The moral of the story, is that if someone is experiencing difficulty witht he reliability of switches, have a peek at the output of the power supply on a scope while the switch operates!

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

marty

Hi All;
One of the reasons I have asked is, as some of you may know, I have been Having a Load of trouble getting my own switch to work..
One of the possible reasons that has been proposed is that my Power Supply is too small.. Mine is a 52-58 Volt Supply at 1.5 Amps..
I have three units connected at the present, a LineFinder, a Selector, and a connector, along with 9 L&CO relays, and two other misc. relays..
Dave, Your addition of a Large Cap, intrigues me.. I'LL have to see what I have here..
THANK YOU Marty

DavePEI

#8
Hi Marty:

Yes, I had read that on the TCI list, and that is why I mentioned it. 1.5 amps should work ok, but will be marginal, as release can take much more. When the relays release, it will be quite marginal. If you can find a large cap with a high enough voltage rating, it should help even out the voltages some even when switches release. I think mine is rated at 70 volts, leaving some buffer from the 48 volts. I am pretty sure that your supply would work better with an Electrolytic across its output.

Some of the old large mainframe computers used such caps in their power supplies, and you should be able to find something suitable fairly easy. Remember, the highest capacitance you can, with at least 70 volt rating. The bleeder resistor should by 5 watts or more at a high enough resistance to bleed it slowly.

Dave

Quote from: marty on March 29, 2013, 08:39:37 AM
Hi All;
One of the reasons I have asked is, as some of you may know, I have been Having a Load of trouble getting my own switch to work..
One of the possible reasons that has been proposed is that my Power Supply is too small.. Mine is a 52-58 Volt Supply at 1.5 Amps..
I have three units connected at the present, a LineFinder, a Selector, and a connector, along with 9 L&CO relays, and two other misc. relays..
Dave, Your addition of a Large Cap, intrigues me.. I'LL have to see what I have here..
THANK YOU Marty
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

marty

Hi All;
Dave, the Cap I found is a 5000 Mfd at 450 volts.. I found another one as well, but its voltage rating is too low, its 66000 Mfd, but only 30 VDC, So I can't use it..
THANK YOU Marty

xhausted110

#10
marty, mine is 48 volts at 4 amps. it is an original western/lorain electric.
- Evan

marty

Hi Xhausted;
That is most likely what I need.. Where did You find Yours ??
Who is your supplier for SxS units ??
I would love to see more video's !!!
THANK YOU Marty

xhausted110

#12
I get them from my friend Keith H. In Michigan. I have made a lot of progress since my last step video I will make another video soon.

-Evan
- Evan

AE_Collector

This ought to do it for you. I believe it is 50 Amps output. This is the power supply for a GTX400 (Hitachi) Crossbar PABX.

Bonus; Ringing, tones and interupters are all inside as well. It must weight 100 pounds though, how would you like me to ship it? :)

Terry

marty

Hi Xhausted;
Have you made any progress on Your LineFinder ?? Since the last video.. My LineFinder did the same thing, and I found a wiring error.. I am after writing this posting going to try my Linefinder again, and after I do some more wiring with my L&CO relays to get all the correct levels set.. I will let You know IF I make any more progress..
THANK YOU Marty