Power distribution vs terminal block what's the difference

[aet]

Hello,

I find myself confused again.

 I bought a power distribution block for my layout not sure how I would use it, if someone could explain its applications I would appreciate it. What is the difference bwt a power distribution block and a terminal block on a DCC layout?

 

Thanks

Drew T.

[Texas Zepher]

I bought a power distribution block for my layout

A DCC power distribution block?

not sure how I would use it

so why did you buy it?

What is the difference bwt a power distribution block and a terminal block on a DCC layout?

A power block is a set of track electrically insulated from the rest of the track (eg. a block) that is powered by its own DCC power unit. The distribution block is the power supply, DCC signal generating uint, and wires used to power that given block.  One would want to divide the layout into blocks for a couple of reasons.  First is to provide more power for many locomotives on the layout without using a high Amp power supply.  Each block can have its own 5 Amp power supply.  An example would be doing 4 blocks with a 5 Amp supply would be 20 Amps for the whole layout.   The second reason one would want to do power distribution blocks would be to isolate short circuits.  IF the layout was all one block a short circuit anywhere would stop anything.  On the same layout separated into the 4 block example, a short would only shutdown 25% of the layout.  The larger the layout the more important this is.  

A DCC power distributor (which is what I think you have purchased), accomplishes the second goal of short circuit isolate without adding additional separate power supplies.   That is it divides the output from a single DCC power supply into separate outputs that can be connected to separate blocks.  They act as totally separate DCC power supplies except that they don't add additional power. 

A terminal block is just a place where a power feed comes in and can have multiple leads coming out of it.  It is often a set of lugs or screws on some sort of mountable strip.

 

[Don Z]

Drew,

Are these the 2 items you purchased?

Don Z.

[aet]

 Don,

yes those are the ones

 

Drew

[larak]

Drew,

 The power distribution block takes the place of two terminal strips and the need for you to create little loops of wire to feed one row of each strip. The block contacts are chained together on the PC board.

+ in one side, - in the other and all "blocks" or power districts out from 1-12 in pairs.

Functionally they are the same. 

Karl 

[twcenterprises]

I use the terminal strips to connect my drop feeders (thin, phone guage wire), to my bus wires (something like 16-18 guage).  At some point, even though I will switch to DCC, I will install a control panel with DPDT (center off) toggle switches to be able to disconnect certain tracks, set up a programming track, and to be able to use DC for locos that have not had decoders installed.  Eventually, I plan to decoderize every loco, but with over 70 on the roster, that may take a while.  Anyway, I made a couple of "daisy chains" under the layout using crimp on spade connectors, the ones where you can loosen the screw and slip them in, and tighten the screw.  I simply installed 2 wires on each one before crimping (except the last one on a terminal strip).  I'd post a picture, but I need a new battery for my camera.

Brad 

[bearman]

I'm using the second kind that Don Z shows for the same purpose as twcenterprises.  The second set is from Radio Shack called terminal barrier strips and you can get 2 position all the way up to 8 position blocks in multiples of 2. The beauty of those is that Radio Shack also sells jump strips that fit those blocks eliminating the need to jump each terminal set with wires.

[twcenterprises]

I have some that are 14 position blocks.  They are quite old, not sure how old, and probably either came from some sort of industrial source, or parts for some industrial machine.  My dad worked for Nabisco, and he got them from there somewhere.

I used the 8 position blocks under my layout, both because the larger ones were overkill, and also because I had the 8 position ones handy, and the others were buried in some storage box somewhere. 

Brad 

[Pruitt]

I use the dual-row terminal blocks in varying sizes all over my layout. You can get them from two to ten positions in one-step increments, and in two-step increments above that (12, 14, 16, etc.). I buy mine from Digi-key. I buy eight position or less because above eight positions the cost goes through the roof (so if I need more than eight positions, I divide the total by two and use two of those size blocks).

Here's a couple of example of where I use them.

Power distribution on my hidden trackage (helix in this case)- right next to the track:

Connections from my control panel to the layout:

[bearman]

I use 4 to 8's and try not to connect feeders to the jump strip side, and leave at least 2 terminals open in case I have to go back and add more feeders later on.  There are four Radio Shacks within 20 minutes of my house and for a while one of them, the closest, was sold out w/in ten minutes of opening.  Evidently there is some other model railroader who, according to the clerk in the store, showed up every Wed at opening when their stock was replenished and would just wipe them out of their barrier and jump strips.