terminal block wiring

[tjm]

I could use some info on how to use terminal blocks.How to wire,how many to use etc.I have a small (and incomplete) 4x7,n scale.Any help is welcome.

Thanks

[MisterBeasley]

They're a nice way to organize certain things, but they don't have any magical properties.  I just installed a turntable and roundhouse.  I used a 4-section terminal block for the turntable (2 for the track power, 2 for the motor) and an 8-section block for the roundhouse stall tracks and interior lighting.  I like the screw terminal connectors for things like this, because they're easy to take off if I have to remove the entire unit for maintenance or to do scenery around it.

I've also put in a few of them for "wire management."  Things like structure lighting buses lend themselves well to this kind of organization.  I've used a few to control the chaos around some relays used in parallel with twin-coil switch machines to control signals.

On the other hand, for ordinary turnout wiring or track power, I find it cheaper and just as easy to run wires point-to-point and solder the connections.

[Anonymous]

Wiring

I've found this article to be very helpful for me when I first started wiring my layout.

LilBeckett

 

[larak]

I use an 8 position block under each tortoise. All wires from tortoise to block and only the needed ones from there onward.

I also use sets of 8 position blocks where control panel wiring transitions to under layout wiring.

I think that they are essential for any removable item. They also add a lot of troubleshooting capability and some neatness.

Shop around and buy them in bulk. Don't worry if some have unused connections.

When connecting  stranded wires either tin the wires or apply spade terminals. Solid wire can be wrapped around the screw (clockwise only) but I like terminals for everything.

Be methodical about your wiring. Every connection is a potential point of failure.

Good luck. 

Karl 

[SteelMonsters]

In my experinece, crimp connectors must be done right or they fail. The problem is usually that you can't see the problem. Bare wire doesn't have that problem with terminal strips. I dealt with just this problem at my club last week.

 

Terminal strips are best used with labeling for easy trouble shooting. Just because you know what it is and does now, doesn't mean a year or two from now you will. Also, always give yourself extra slack in wiring such as make a U turn at a panel. This makes troubleshooting and repairs easier or even possible when you can unscrew a P clip and get some slack. I know someone that is frustrated at another club because someone wired an area to the point shere there is no slack at all. The plywood expanded with a rise of humidity which pulled the wiring causing random seperations. He ended up having to remove all of the old wiring and start over.

[tomikawaTT]

My wiring (analog DC, MZL system, COMPLICATED) is all done from terminal block to terminal block - control panel block to zone distribution block to local distribution block.  Only the wires from the controls on the face of the panel to the control panel block and from the local distribution block to the 'end user' (rail, switch machine coils/contacts, signals, structure lights...) are soldered at the end not wrapped around a terminal.  ALL terminals are clearly labeled with wire identification codes, and all of my circuitry is documented in detail.

Any resemblance between this and the way aircraft are wired reflects my 26 years in the aircraft maintenance business.

I make my own terminal blocks, using chunks of board or plywood, #8 machine screws, nuts (2 per screw) and LOTS of washers (two touching wood, plus 1 for each wire on a given terminal.)  This allows me to customize each block for its purpose, and is a LOT cheaper than buying the commercial variety.  (Some of my terminal blocks have 100 or more terminals.)

Rather than using stake-ons, I simply bend the twisted end of stranded wire and solder-soak it.  That makes the end 'solid' enough to hook around a terminal post without the danger of flying strands - eliminating a potential source of shorts and/or mystery circuits.

My method takes more time up front, but pays dividends in ease of troubleshooting and reduced problems later.  I will admit instantly that it is probably gross overkill for a small, uncomplicated layout.

Chuck (modeling Central Japan in September, 1964)

[claymore1977]

Somethings I am used to doing (much like tomikawa, only mine is a decade as a Navy Nuke Electrician):

 

• Label each wire or pair of wires at each end and a few points in between.
• Develop a basic wiring code, aka MTP-xx = Main Track Power Block xx, TMP-xx = Turnout Machine xx Power, 12VAUX-xx = 12V Auxillary Power item xx, JUMPER = short jumper wires :), etc, etc.
• In addition to consistant wiring lables, associating wire colors to the specific type of circuits also helps immensely. "Purple & Black...oh yeah, that a 5Vdc LED power of some sort..."
  
•  Route cables like city roadways, don't just run them directly to the load.  Yes this uses extra wire, but keeping the install clean and organized is worth it in the long run.
• Label each terminal block (TB-13, TB-15, etc) and, if you are particularly detail oriented, keep whats called a "TB-Tab."  basicly a series of charts detailed what, exactly, is hooked up to each terminal on any given terminal block. (this could be a huge job, but works well when there will be more than one person working on the electrics)
• Terminal strips at source and load. 
  
• Provides a nice place to land a multimeter/o-scope probe if you need to troubleshoot. 
  
• Allows for ease of load component replacement.
• Allows for ease of adding new components, especially when piggy backing off an existing circuit.

Well, thats my $0.02 anyways, if I think of more I will add them to the list.  Hope this helps some.

[claymore1977]

I will admit instantly that it is probably gross overkill for a small, uncomplicated layout.

 

My first E-Div Chief always used to say:

"There's never a bad time or place for a Good quality job.  Take your time maggot, sleep is for wimps!" 

[MisterBeasley]

As this topic has stretched a bit (all the good ones do that) into a more general discussion of good wiring techniques, I'd like to suggest getting multiple spools of different-colored wires and using them in a consistent manner.  Sure, you can get 10 rolls of black and use it for everything, and it will work fine, but when you have to trace one of those wires it's a lot easier if it's "the green one."

My layout is a 5x12 foot "island" mounted on casters so I can push it around the room, tucking it under the roof line when "the family" wants to use the the family room, and pulling it out when I'm working on the back side.  I realized early on that I could actually turn the whole thing 180 degrees, making the back side into the front side.  This would give me a different viewpoint on the layout, and allow me to work on the details more easily.  So, I wired my control panels each with a single "wiring harness" through the centerline of the layout.  I can remove the panel from the fascia and re-mount it on the other side.  By inverting the panel when I do this, the turnout schematic maintains the right orientation with respect to the layout, too.

[bearman]

I'm using them for my track power.  Generally I like to use a size that will provide one or two open terminals in case I have to go back and add another set of feeders.  I also have purchased a label making machine, only $20 or so at Staples or OfficeMax, and label each terminal as I go along and keep a main schematic of my trackplan up-to-date as I lay the track and wire it.  This way, at the end, I will know which wires on which terminal block are feeding which section of track.  After about 10 ft of track wiring, the pain of the labeling suddenly becomes obvious as a future time saver if necessary.  If you do use terminal blocks, get ones that will take a jump strip and invst in the jump strips as well.  Radio Shack carries and assortment. 

[Chartiers]

Keeping the wiring clean and using marked terminal blocks sure makes debug, and changes, easier.

[bearman]

You betcha.  I use 1/4" plastic coax cable clamps to to keep the power bus from sagging onto the feeders. Works like a charm.

[woodlandtoots]

Lots of good techniques have been mentioned already. I definently agree with Steelmonster. Leave plenty of slack at each terminal. I like to leave about 3-4" more wire than necessary. That way it's much easier to work with when you need to attach it to the terminal, or troubleshoot. And if you have a bad connection with a spade connector, you just cut it off and put a new one on without worrying that the wire will get too short.

There are several good ways to bundle and shape the extra length of wire so you don't have a big "wad" that looks unsightly. I like to use stick on cable tie bases and small cable ties. Also I like to use spiral wrap plastic to bundle the wires as necessary. Its easy to put on and easy to take off when troubleshooting.

You'll not regret having several extra inches of wire at each terminal. That comes from my experience in the electronics assembly industry.

Woodlandtoots 

 

 

[Medina1128]

An easy way to give your jumper some slack is to wrap it around your thumb somewhere along the run. This puts a loop in it, so if you need to resolder it you'll have enough after you've cut some out of the wire. I use the mini tie-wraps when the area is wired. This keeps things neat, especially under the control panel. I use a DYNO label maker to label the circuits. I also use terminal blocks to simplify troubleshooting. I am using DC with common rail wiring. One terminal from each power pack (cab) goes to a common block, and the other terminal from each power pack has its own terminal strip. The nice thing about using terminal blocks is that if the polarity is reversed, it's easier to reverse the wires than to cut and resolder the jumpers.

[Anonymous]

This seems as good a place as any for this question.

 I found all these posts very informative, especially that article LilBeckett posted here, but all this is for DC wiring. Is it easier or harder to wire for DCC? How would this set up work with the isolation blocks?

[claymore1977]

Easier or harder... hrm, could be either.  In theory, DCC is much simpler to wire as it removes the extra wiring & toggle switches that come with a DC Cab control setup.

But as for the use of terminal strips... not really DC or DCC dependent.

All these situations lend themselves easily to use of a terminal strip:

• A wire attaching to a component
• A wire running into a controlpanel
• A wire running between two parts of a sectional layout
• Anywhere two wires splice
• etc.

...so as far as terminal strips goes.... DC, DCC, AC.... doesnt matter!

[Pruitt]

Here's a couple of views of how I use terminal blocks in feeders to track. The first shot shows the distribution node for a sub-buss connection to the track feeders on my helix. Each tier has two sub-busses - one on each side of the helix.

This second photo shows the buss to sub-buss distribution nodes at the base of the helix.