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Discussion Starter #1 (Edited)
Help! Another power question!
I have an in door layout with about 25 signals and switches and 60+ LGB 17000 17100 Track Contacts. I have been powering them with an outdoor lighting system transformer with an output of 15 volts AC. I am finding that if 3 or 4 of the track contacts are turned "on" at the same time, occasionally a switch or signal that should be opened or closed does not happen...resulting in a train wreck.

I am using 16 gauge wire as the main bus and then smaller 18 and 20 gauge off it to the individual components.
I believe I might need more voltage (18v AC? 20v AC? 24v AC? ) but don't want to overload the reed switches and possible fuse or damage them...

The power output of the transformer is about 300 watts...I am thinking of upping it to 1000 watts. But I am not certain of the voltage requirement.

So here is my question: does anyone know the range of voltage that is best suited for the track contacts (reed switches), switches, and signals? :rolleyes:
 

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Super Modulator
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It's not really voltage but current that hurts the contacts in reed switches.

It seems that the output voltage is sagging when you put too much load.

Since you need AC, all you can do is get a transformer of the same voltage but more wattage.

The voltage ratings of signals should have been published in their respective manuals.

Greg
 

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i am using LGB reeds (and similar) since the early '80s.
my personal experience:
at 16 or 18 V AC one or two switch/signal motors per reed work fine. (at 14 V AC only one)
when using three motors hooked to the same reed, i had often malfunctions.
either, that not all switches reacted always, and/or that reeds burned out in closed position.
 

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Super Modulator
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Korm brings up a good point, too many things connected to a single reed could be too much current.

But as I read the op: " I am finding that if 3 or 4 of the track contacts are turned "on" at the same time,"

I interpret this not as several things hooked to ONE reed, but SEVERAL reeds, each connected to ONE thing. No overcurrent on the reed, just overcurrent on the total system.

But Korm's warning is a good one to remember.

Greg
 

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I use the 18 volt AC transformer but I did install the LGB booster for outdoors and got much better results. Also I only do 1 epl drive at a time.
 

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I interpret this not as several things hooked to ONE reed, but SEVERAL reeds, each connected to ONE thing. No overcurrent on the reed, just overcurrent on the total system.


oh, i didn't think of that possibility.

but in that case there should be two easy work arounds.

either install the reeds with more distance between each other, or be parsimonious - don't buy the expensive (and large) LGB magnets, but smaller ones.




edit:
but i never had the several reeds problem. using a 60 VA max. 4 Amp transformer, that has plugs for up to 25 V AC.
 

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Super Modulator
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Some more thoughts:

15 volts, 300 watts sounds suspiciously like a Malibu outdoor lighting transformer.

That should be ok for 20 amps... but they do drop voltage quickly on a load.

So, I think 15 volts is marginal for LGB switch motors, and if you do a few at a time, you are dropping the voltage too much.

I should have caught the low voltage earlier. I think an 18v 300 watt would be fine, but I suspect your signals are 12v.

So a little more information on the desired voltages for the signals and the other accessories. You might have a difficult problem to solve.

Greg
 

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Greg,
if i remember right, the innards of the epl switch motors and the epl signal motors are identical.
so, if he is only using LGB components, a signal should equal a switch-motor.

i just had a look: my smallest LGB/Playmobil transformer/controler has an AC output of 14 Volt (14VA and an automatic reset fuse of 1.1 Amp) for epl use.
so under "normal" conditions everything from 14 V to 18 V(20?) AC should be good for one user at a time.

i ignore, how much these boosters can add.

but i do not see, why two reeds with one switch each should be using more power, than one reed with two switches.

or could it be, that these other round things(??) (alzheimer light made me forget their name - 7K820 76 is written on them) that are wired in paralell with the reed, could fail too?
(see below)

 

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Help! Another power question!
I have an in door layout with about 25 signals and switches and 60+ LGB 17000 17100 Track Contacts.

I am finding that if 3 or 4 of the track contacts are turned "on" at the same time, occasionally a switch or signal that should be opened or closed does not happen...resulting in a train wreck.
:rolleyes:

What does this even mean???


Literally, "3 or 4 of the track contacts are turned on at the same time" means that 3 or 4 engines are tripping the reed switches simultaneously, or fewer engines are tripping very proximate reeds simultaneously.


But I think he may mean that if 3 or 4 of the reed switches trip 3 or 4 signals and they are all turned on at the simultaneously, the turnouts don't throw well.


The problem is you guys are speculating on an unknown and the OP hasn't come back to clarify things.
 

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The way I see it, the problem is simply that there is not enough voltage when the one 15 volt AC transformer has to drive 3 0r 4 EPL drives at the same time.

15 VAC is marginal to start with, the AC output of the LGB power packs is nominally 18 VAC and they are only designed to drive a maximum of two EPL drives at the same time.
I would get an 18 VAC or even a 20 VAC transformer, but one of good quality that is well regulated so the voltage doesn't drop too much when driving 4 EPL switch drives.

As Greg mentioned, voltage is not the issue as far as the reed contacts are concerned (at least not when we're talking 15 vs 18 vs 24 volts) - curent is.
I wouldn't drive more than two EPL switch drives with a single LGB reed.
 
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