# Thread: So why is it called a 3-way (or a 4-way)?

1. Originally Posted by charlie b
But that media arrived at the valve via a path that is different from the two it can take as it leaves the valve. There are three "ways" fluid can flow: In, Out-to-the-left, and Out-to-the-right.
In a three way valve doesn't the media only flow one path? Switch it and it flows the other. Now a 4 way valve can have two different paths after switching there is still only two paths but the source of each has been alternated. Similar situation with three way and 4 way switches.

If you are stopped in the middle there is potentially three different ways to go. But electric current or hydraulic media does not stop in the middle and then have a choice to go any of the three possible directions. The direction it came from is likely not even possible to go back because of voltage or pressure so that leaves only two ways to go from this point.

Still makes no sense why the names are what they are.

Originally Posted by K8MHZ
If you have had some training and experience in hydraulics you would find that it's not that confusing.

I remember starting out as a maint. tech in a foundry that a bunch of presses. Looking at the hydraulic schematics was like looking at hieroglyphics. I had a grumpy boss that knew all about the valves and started teaching me about them. I also went to Parker-Hannefin's course on industrial hydraulics. After that, I could look at the schematics and know exactly what I was looking at.

It's really not rocket surgery.
I don't really find the hydraulics valves that confusing, just the reasoning for the names 3 way and 4 way, just like for switches.

2. My favorite explanation: It's a SPDT switch with three 'ways' it can be used:

Connect common to terminals on left, Connect common to terminals on right, and Off (shown)

3. Originally Posted by 480sparky
My favorite explanation: It's a SPDT switch with three 'ways' it can be used:

Connect common to terminals on left, Connect common to terminals on right, and Off (shown)
Got one for the 4-way?

4. Originally Posted by mivey
Got one for the 4-way?

. .

5. Originally Posted by ritelec
post #5. Yes...

Can we talk about switches in a run now? eg. system?

Actually can you talk.............I'll listen...........?
That may be a good subject for another thread.

I have a method of wiring 3 and 4 way switches that eliminates almost all the confusion. They don't have to be in a row and they can be fed from any switch.

Is that what you are looking for, different ways to run wire to these multi-switch systems?

I need the practice, too, since now I have to pull a neutral to all the boxes and want to make sure my method doesn't need amendment, just an extra conductor.

6. Originally Posted by K8MHZ
That may be a good subject for another thread.

I have a method of wiring 3 and 4 way switches that eliminates almost all the confusion. They don't have to be in a row and they can be fed from any switch.

Is that what you are looking for, different ways to run wire to these multi-switch systems?

I need the practice, too, since now I have to pull a neutral to all the boxes and want to make sure my method doesn't need amendment, just an extra conductor.
Was thinking about another thread.....but I understand what it is, just not the rational of why it would be called 3 way, 4 way , 5 way, 6 way... maybe it also has to do with the point being fed?

2-switches 1-light outlet = the 3?....3-switches 1 light outlet = the 4???

Am I looking for different ways to wire multi-switch systems? Thanks, I'm ok with it...... but as you mentioned, that whole neutral at each switch location thing???? That's going to me interesting.

New type of wire? (but don't they already make a nm white-blk-red-blu)........

7. Originally Posted by ritelec
Was thinking about another thread.....but I understand what it is, just not the rational of why it would be called 3 way, 4 way , 5 way, 6 way... maybe it also has to do with the point being fed?

2-switches 1-light outlet = the 3?....3-switches 1 light outlet = the 4???

Am I looking for different ways to wire multi-switch systems? Thanks, I'm ok with it...... but as you mentioned, that whole neutral at each switch location thing???? That's going to me interesting.

New type of wire? (but don't they already make a nm white-blk-red-blu)........
Maybe I'm not understanding you. Who calls multi-switch circuits 5 way, 6 way, etc.? I have never heard them referred to in that manner.

The new code would require a neutral at each switch location.

So as far as wiring methods for a 3 or 4 way system using 3 wire... the neutral would have to get fed through from your first 3 way box to your last 3 way box........You wouldn't be able to bring the
return back to your first 3 way box without using a 4 wire nm cable.

I'm not too familiar with the new switching that's coming out..but as they require a neutral and is the reason for this code change..... do they not also require a hot????
Can theses new switches be installed in a switch box where a neutral is present in that switch box but you only have travelers at that location......???

Maybe they will start making 5 wire nm cable with ground..............................
Maybe 5 wire nm with a ground and an isolated ground..................................
Maybe 5 wire nm with a ground and an isolated ground that comes with a toy surprise like cracker jacks (but not those cheap surprises like they come with now)...............maybe with something like a like a cool compass or mood ring or laser level!!!!
Last edited by ritelec; 03-03-12 at 10:48 AM.

9. Originally Posted by ritelec
I looking for different ways to wire multi-switch systems? Thanks, I'm ok with it...... but as you mentioned, that whole neutral at each switch location thing???? That's going to me interesting.
Different method - not so out of ordinary but not common for lighting - multi station start - stop buttons and contactor with holding contact.

Still need same number of wires run to all of the stations though. Could do it with low voltage though. Shouldn't reqire a neutral either - I would think, maybe they still would want a control circuit common or L2.

10. Originally Posted by ritelec

New type of wire? (but don't they already make a nm white-blk-red-blu)........
Yep, now you can get NM-B with an extra neutral.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•