Basic voltage questions UPDATE 4/3/20: changed switch yard lighting strategy (with pictures). Thanks for your help!

Coils eat a good amount of power. Think about it; enough heat to overheat and melt stuff if you go without a rest or park on them  

So similar work heat is at the supply, it just takes time to build up.  The more amps you use, the more heat builds in the supply too. I don't think the modern units "run cooler" per watt or anything. If they do run cooler I'd guess it's more because of the cooling fans...needed for the modern electronics which are a little less heat tolerant than transformer windings and contacts alone. (new sine still has windings )

Gramps used to run hot enough to startle you. You wouldn't necessarily want to rest a hand on the top plate after a hard session.

2v drop doesn't seem much of drop. Didn't you have a light common issue? Is it possible you went light elsewhere and left it alone "for now" and forgot? Maybe a screwy path? (electricity takes the shortest and or easiest route, maxing it, then moving excess needs to the further path... it's possible to be "amp ready" but screw up a path somewhat if your too clever and stingy with power delivery.

CoastsideKevin posted:

...

If the ZW is on without the Z4000 and so obviously not running trains, the ZW stays pretty cool. However once I turn on the Z4000 and start running trains, the ZW gets pretty warm after a half hour or so. After an hour it is hot, but not burning hot.

To be clear, if the ZW is on without the Z4000 does the ZW stay cool after a half hour, after an hour?  Related, is it the mere act of turning ON the Z4000 that causes the ZW to start warming up?  So if you remove the engines from the track and crank up the Z4000 voltages to 12V (or whatever), does this then affect the ZW temperature?  With nothing on the track, what do the Z4000 AMP meters read as you move the handles up and down?

Separately, does your meter measure AC current?  If so, what are the AC voltage and current readings for ZW posts A and D?  Or if you meter does not measure AC current, would it be possible to temporarily move the Z4000 to the ZW and connect the A and D circuits to the two Z4000 outputs?  Crank up the Z4000 throttles to whatever voltage you set the ZW A and D, then note the AMP readings.

Finally, can you estimate the wiring distance from the ZW to the distant problem switch and also the wiring distance from the problem switch back to the manual lever controller?  Do you run 3 control wires from the switch back to the controller?

Note that even using LEDs, you are powering 36 of them (18 switches, 2 LEDs on at a time per switch).  So if each LED draws, say, 10-15 mA, that's maybe 1/2 Amp which can easily translate to a 1-2 Volt drop over a long distance.  And of course when you then actually fire the switch the current drawn by just that distant switch goes up to more than 1 Amp which means the voltage loss from the transformer to the switch solenoid much more than 1-2 Volts.  You can briefly test this line of reasoning by temporarily increase the post A voltage to, say, 18V instead of 14V.  I assume by problem switch you mean sluggish or anemic switch action as opposed to a crisp snap action.  With 18V does the distant problem switch improve?

CoastsideKevin posted:

Hi all,

I have a pretty simple attic layout. Two districts powered by a Z4000 (about 400’ of track including sidings), no command except LC+. For accessories, I use post A on a ZW for constant voltage to the 18 022s and 12 UCS. All bulbs in the 022s and 022c’s are LED. Post B is dedicated to my 282 crane and post C to my two 262 crossing gates. Post D is for lighting only. 3/4 of my lighting is LED but I do have some incandescent bulbs in a few of my postwar floodlight towers (4 banks of 8 bulbs on two 194 towers). I am using 14ga wire for all my track power and 16ga for the 022 daisy chain and the UCS wiring, quite small gauge for the lighting, probably 22ga or so.

If the ZW is on without the Z4000 and so obviously not running trains, the ZW stays pretty cool. However once I turn on the Z4000 and start running trains, the ZW gets pretty warm after a half hour or so. After an hour it is hot, but not burning hot.

 

Thanks for your thoughts on this. Perhaps it’s time to replace the old ZW?

Kevin 

The ZW is not connected to any circuits powered by the Z4000 correct? As others mentioned, does the ZW get hot without running trains, just being on and powering the circuits connected to it?

Working with multiple transformers, track and accessory,   Common/outside rail, often is connected/one and the same. 

P (power in watts) = V (volts) X (amps)

20 watt lamp,  operating at 20 volts,  would draw 1 amp.  

For approximate  discussion.   

Kevin, you have some strange gremlins at work there. There is no way switch machine coils are causing the ZW heating because they are a momentary load...unless they aren't. If you have trains stopping on the non-derailing rails of the O22s those coils would then be drawing continuously and they would also be heating up. Quickly.

You need to go through all your connections and make sure that somewhere you don't have the transformers connected in parallel.  If they are that could be the cause of heating when both are on together.  

Keep in mind that your floodlights alone are using up about half of the ZW's rated output.

Kevin- if the handles on the Z-4000 are up and the ZW is off, do you see voltage at the ZW terminals? Sounds like as others have said you are backfeeding one from the other. They are in phase so it's not causing a short but it will add resistance on the transformers.

Rob, you are referring to these?

my postwar floodlight towers (4 banks of 8 bulbs on two 194 towers).

geysergazer posted:

Rob, you are referring to these?

my postwar floodlight towers (4 banks of 8 bulbs on two 194 towers).

Yes. 2-3 watts each bulb. The ZW is about 180-190 watts continuous output.

Adriatic posted:

Coils eat a good amount of power. Think about it; enough heat to overheat and melt stuff if you go without a rest or park on them  

So similar work heat is at the supply, it just takes time to build up.  The more amps you use, the more heat builds in the supply too. I don't think the modern units "run cooler" per watt or anything. If they do run cooler I'd guess it's more because of the cooling fans...needed for the modern electronics which are a little less heat tolerant than transformer windings and contacts alone. (new sine still has windings )

Gramps used to run hot enough to startle you. You wouldn't necessarily want to rest a hand on the top plate after a hard session.

2v drop doesn't seem much of drop. Didn't you have a light common issue? I have had a couple of shorts in the past but solved those. In the very beginning, I had the common going to the center rail but have since changed that. Is it possible you went light elsewhere and left it alone "for now" and forgot? Maybe a screwy path? (electricity takes the shortest and or easiest route, maxing it, then moving excess needs to the further path... it's possible to be "amp ready" but screw up a path somewhat if your too clever and stingy with power delivery. This is intriguing but I'm not exactly understanding the situation you are describing. I did add extra common wiring to both outside rails because I'm using Gargraves on about 70% of the layout.

 

Thanks! A couple of thoughts above..

stan2004 posted:

CoastsideKevin posted:

...

If the ZW is on without the Z4000 and so obviously not running trains, the ZW stays pretty cool. However once I turn on the Z4000 and start running trains, the ZW gets pretty warm after a half hour or so. After an hour it is hot, but not burning hot.

To be clear, if the ZW is on without the Z4000 does the ZW stay cool after a half hour, after an hour?  Yes, that seems to be what I'm experiencing. Related, is it the mere act of turning ON the Z4000 that causes the ZW to start warming up?Checking this over the next hour or so. So if you remove the engines from the track and crank up the Z4000 voltages to 12V (or whatever), does this then affect the ZW temperature? Experimenting with this now - stay tuned. With nothing on the track, what do the Z4000 AMP meters read as you move the handles up and down? If I move the left handle (inner district) up to 12v, the left ammeter shows .1a and the right shows .1a. If I move it up to 24v, it goes to .1a and .2a respectively. If I move up the right handle (outer district), I get 0.0a regardless of voltage.

Separately, does your meter measure AC current?  Yes. If so, what are the AC voltage and current readings for ZW posts A and D?  I get between .5a and .6a on both A and D at 14v. Or if you meter does not measure AC current, would it be possible to temporarily move the Z4000 to the ZW and connect the A and D circuits to the two Z4000 outputs?  Crank up the Z4000 throttles to whatever voltage you set the ZW A and D, then note the AMP readings.

Finally, can you estimate the wiring distance from the ZW to the distant problem switch and also the wiring distance from the problem switch back to the manual lever controller?  Probably about 18 feet. Do you run 3 control wires from the switch back to the controller? Yes.

Note that even using LEDs, you are powering 36 of them (18 switches, 2 LEDs on at a time per switch).  So if each LED draws, say, 10-15 mA, that's maybe 1/2 Amp which can easily translate to a 1-2 Volt drop over a long distance.  And of course when you then actually fire the switch the current drawn by just that distant switch goes up to more than 1 Amp which means the voltage loss from the transformer to the switch solenoid much more than 1-2 Volts.  You can briefly test this line of reasoning by temporarily increase the post A voltage to, say, 18V instead of 14V.  I assume by problem switch you mean sluggish or anemic switch action as opposed to a crisp snap action.  With 18V does the distant problem switch improve? Yes, that is exactly what happens. Servicing the switches has helped immensely, but I still have a couple that need a temporary boost to get them to fire completely.

Lots to explore here - I'm doing further testing now, but above are some answers. Thanks so much for all these ideas!

BobbyD posted:

CoastsideKevin posted:

Hi all,

I have a pretty simple attic layout. Two districts powered by a Z4000 (about 400’ of track including sidings), no command except LC+. For accessories, I use post A on a ZW for constant voltage to the 18 022s and 12 UCS. All bulbs in the 022s and 022c’s are LED. Post B is dedicated to my 282 crane and post C to my two 262 crossing gates. Post D is for lighting only. 3/4 of my lighting is LED but I do have some incandescent bulbs in a few of my postwar floodlight towers (4 banks of 8 bulbs on two 194 towers). I am using 14ga wire for all my track power and 16ga for the 022 daisy chain and the UCS wiring, quite small gauge for the lighting, probably 22ga or so.

If the ZW is on without the Z4000 and so obviously not running trains, the ZW stays pretty cool. However once I turn on the Z4000 and start running trains, the ZW gets pretty warm after a half hour or so. After an hour it is hot, but not burning hot.

 

Thanks for your thoughts on this. Perhaps it’s time to replace the old ZW?

Kevin 

The ZW is not connected to any circuits powered by the Z4000 correct? As others mentioned, does the ZW get hot without running trains, just being on and powering the circuits connected to it?

That is correct. At this moment I am letting the ZW run on its own for .5 hour, then will power up the Z4000 and let it sit for a half hour and see if the ZW gets hot.

Mike CT posted:

Working with multiple transformers, track and accessory,   Common/outside rail, often is connected/one and the same. 

P (power in watts) = V (volts) X (amps)

20 watt lamp,  operating at 20 volts,  would draw 1 amp.  

For approximate  discussion.   

 

 

Thanks, Mike. I have the whole common circuit of both transformers connected together. 

geysergazer posted:

Kevin, you have some strange gremlins at work there. There is no way switch machine coils are causing the ZW heating because they are a momentary load...unless they aren't. If you have trains stopping on the non-derailing rails of the O22s those coils would then be drawing continuously and they would also be heating up. Quickly.

Hi Lew-  Yes, I agree.  I don't believe I have the issue of the trains sitting on the non-derail rails. Trains generally keep moving along.

It is something I have been scratching my head over for awhile so thought I would put it out to the group. Everything seems to work fine, but the odd part is that the ZW runs cool on its own, but only starts to heat up significantly when I'm running trains with the Z4000.

Dick Malon posted:

You need to go through all your connections and make sure that somewhere you don't have the transformers connected in parallel.  If they are that could be the cause of heating when both are on together.  

Hi Dick - yes, that would make sense that it would do that, but I don't see any evidence of that on the meters. The only part of the ZW that is getting near the track is post A 022 and UCS constant voltage. Possibly current from the Z4000 getting back to the ZW through one or more of those?

ADCX Rob posted:

Keep in mind that your floodlights alone are using up about half of the ZW's rated output.

Right, Rob, that is a lot. Plus I have another 15-20 incandescent bulbs at various other places on the layout, so I think the power is adding up. But when I check current on that post D, I only see .6a at 14v. Shouldn't I be seeing more? I trust my meter - it is a Fluke 77. EDIT: These readings were incorrect. See below. Sorry!

RSJB18 posted:

Kevin- if the handles on the Z-4000 are up and the ZW is off, do you see voltage at the ZW terminals? Sounds like as others have said you are backfeeding one from the other. They are in phase so it's not causing a short but it will add resistance on the transformers.

That was my first guess, but I looked and don't see any voltage at the ZW when it is off and the Z4000 is cranked up to 20v. If I turn the ZW on and up to 8v and crank up the Z4000 to 20v on either handle, I don't have any increase in voltage on the ZW - stays at 8v.

ADCX Rob posted:

geysergazer posted:

Rob, you are referring to these?

my postwar floodlight towers (4 banks of 8 bulbs on two 194 towers).

Yes. 2-3 watts each bulb. The ZW is about 180-190 watts continuous output.

I'm starting to think more and more this might be it. That's a lot of wattage. I count about 50 incandescent bulbs on the layout in total. I always thought the 194s used less wattage because the bulbs are funky and different (lower?) voltage. But if they indeed take 2-3 watts per bulb, that is high and then the added load of the switches and crossing gates might just be enough to get the ZW warm. Still seems strange the ZW stays fairly cool on its own, and also see my question above about only showing .6a on the D post and .5a on the A post. Oddly, I'm seeing about the same on B and C even though those accessories (282 on B and crossing gates on C) are not being activated. EDIT: All these readings were incorrect. Correct amperage is post A: .7a, post B and C: 0.0, and post D (lighting): 4.5a. My apologies for that error.