Notices
Marine Electronics Forum

Switch Panel Wiring?

Old 10-04-2014, 10:25 AM
  #1  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Posts: 4,458
Likes: 0
Received 27 Likes on 20 Posts
Default Switch Panel Wiring?

Is there anything wrong with the common practice of "daisy chaining" a row of switches for the 12v inputs?

I recognize that these casually look like series wiring, but all are actually in parallel.
But if one interconnection fails, everything past that point will go dead. Typically done with individual short loops of red wire. I've had this discussion with house electricians re: 120VAC, and the opinion is best practice is to "pigtail" rather than daisy-chain from one receptacle to the next on the branch, the equivalent of using a busbar in DC circuits.

Maybe run the 12v to each end of the run of switches for redundancy, so that if one connection fails, the rest of the switches still get power from the opposite end?

I would feel more comfortable connecting each switch to a bus bar running adjacent to the row of switches, if there's room.

But, I'm leading toward using the loops, but supplying power to both ends of the run.

thoughts?
Old 10-04-2014, 03:56 PM
  #2  
Senior Member
 
Join Date: Aug 2014
Posts: 291
Likes: 0
Received 4 Likes on 3 Posts
Default

I do a lot of electrical installations and upgrades and there is nothing wrong with it as long as all of the "+" are tied together and they are in parallel. That's how the commercial manufacturers and boat builders do it. There is no need to supply voltage to both ends of the string, as voltage is going to be the same on all parallel legs. I would focus on doing correctly done crimp connectors with heat shrink and using marine grade AWG wire, not SAE and you should be good for a long time.
Old 10-04-2014, 05:16 PM
  #3  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Posts: 4,458
Likes: 0
Received 27 Likes on 20 Posts
Default

Thanks. But, I'm still more comfortable supplying the 12v+ to both ends of the switch string...only involves one extra wire. I do use tinned marine-grade wire, and marine-grade nylon crimp adhesive-lined shrink connectors, but I'm a "belt and suspenders guy". Even use Corrosion-X on all switches and busbars, too. Often use clear "liquid electrical tape" rather than the corrosion spray. Easily peelable, and the clear allows inspection for connectors turning green...plus, prevents screws from loosening due to vibration.

"common practice" and "best practice" are often in conflict. I hate doing things over that weren't done right the first time. Many new boats were wired by Stevie Wonder or Ray Charles...I like neat, parallel runs, and labels at both ends of a run. Still looking for a better labeling system, using a Brother P-Touch machine which I don't like.

A lot has to do with panel location and protection, salt vs. fresh water, etc., but it is always high-humidity, even if splash-proof.
Old 10-04-2014, 05:50 PM
  #4  
Senior Member
 
Join Date: Aug 2014
Posts: 291
Likes: 0
Received 4 Likes on 3 Posts
Default

Let us know if you run across a better labeling system that doesn't break the bank. I'm also using a Brother P-Touch labeler. Not great, but better than nothing. The labels covered with clear heat shrink seem to do OK, but if there's something better, I would try it.
Old 10-04-2014, 07:52 PM
  #5  
Admirals Club Admiral's Club Member
 
Join Date: Oct 2007
Posts: 628
Received 118 Likes on 88 Posts
Default connectors

I am in the same boat so to speak, rewiring my switch panel this winter. I will probably end up running a couple of wires to the individual components as well after I inspect them. The issue I keep running into is how to wire the jumpers. Currently on my world cat they have 10ga wire jumpers using a double male female adapter to attach the 2 wires to the CB. The only other options I have seen are a multi stack connector, or using smaller wire (not desirable) and crimping two wires into one female blade connector (again not desirable). I would like to skip the double stack connector, but can't seem to find the right female connector that can accept 2 10ga wires. I have seen a couple of pics of switch panels that appear to have a connector capable of such a feat, but have been unable to find them. Do they really exist, and if so, where would I find them?
Old 10-04-2014, 08:33 PM
  #6  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Posts: 4,458
Likes: 0
Received 27 Likes on 20 Posts
Default

I always prefer screw terminals rather than push-on quick-disconnects. With screw connectors you can use a ring-terminal, or, if the screws are captive, then a flanged spade/fork terminal, providing more surface contact and greater fastening torque than QDs do. QDs always need filling with silicone dielectric grease for water exclusion.

Regarding the P-Touch labels, I use the exterior-rated ones, and install them as a "flag" rather than applying them linearly along the wire then covering with clear heat-shrink, especially on small-gauge wires. Still don't like either method and the consumables get expensive.
Old 10-04-2014, 09:12 PM
  #7  
Admirals Club Admiral's Club Member
 
Join Date: Aug 2009
Location: VA
Posts: 5,970
Received 436 Likes on 272 Posts
Default

I think it's a better idea to run power from individual fuses in a fuse block to each switch, thence to the load. Each device's ground goes to a buss bar. The only "daisy chain" on switches should be the ground for the lights if they are illuminated switches.

Running power (+12v) to multiple switches in parallel, puts multiple loads on the same circuit, requiring that all such circuits employ wire suitable for the sum of all loads--as there is only one fuse protecting the entire group of circuits.

For example, if you have a VHF (7A), a Stereo (15A), Nav lights (5A), a bilge blower (10A) you have a total potential load of 30A to 40A. You could probably live with a 30A fuse, because it's unlikely all devices would be on at the same time. So that would require that every wire in every circuit be 10ga.

If you ran individual circuits from separate fuses, the wiring could be 14 or 16 ga wires from the fuse block to the switches and hence to the loads.

Remember, the fuse is intended to protect any wire in the connected circuit from overheating and starting a fire in case of a shortcircuit. It's not to protect the devices.

On breaker panels, where the switch is actually a breaker, then a buss bar is used to supply +12V to each breaker. and the proper sized wires run to each device. The buss bar (or daisy chained wire) must be capable of handling the sum of all possible loads and be no larger than the OCPD (over current protection device) upstream of it.
Old 10-05-2014, 01:16 PM
  #8  
Admirals Club Admiral's Club Member
 
Join Date: Oct 2007
Posts: 628
Received 118 Likes on 88 Posts
Default

Originally Posted by Buoy Scout View Post
I think it's a better idea to run power from individual fuses in a fuse block to each switch, thence to the load. Each device's ground goes to a buss bar. The only "daisy chain" on switches should be the ground for the lights if they are illuminated switches.

Running power (+12v) to multiple switches in parallel, puts multiple loads on the same circuit, requiring that all such circuits employ wire suitable for the sum of all loads--as there is only one fuse protecting the entire group of circuits.

For example, if you have a VHF (7A), a Stereo (15A), Nav lights (5A), a bilge blower (10A) you have a total potential load of 30A to 40A. You could probably live with a 30A fuse, because it's unlikely all devices would be on at the same time. So that would require that every wire in every circuit be 10ga.

If you ran individual circuits from separate fuses, the wiring could be 14 or 16 ga wires from the fuse block to the switches and hence to the loads.

Remember, the fuse is intended to protect any wire in the connected circuit from overheating and starting a fire in case of a shortcircuit. It's not to protect the devices.

On breaker panels, where the switch is actually a breaker, then a buss bar is used to supply +12V to each breaker. and the proper sized wires run to each device. The buss bar (or daisy chained wire) must be capable of handling the sum of all possible loads and be no larger than the OCPD (over current protection device) upstream of it.
You are misunderstanding where the "daisy chain" is. It is being done on the input side of the individual fuses / CB's. My positive inputs via a daisy chain to the inputs of the individual CB's for the individual components. This input comes from a master CB and switch. This allows for a master switch and CB to protect the panel, then individual CB's to protect each components circuit. Without this I would not have the option for a master switch, or if I did, then I would have to run 12 wires from the master to the inidividual CB's.
Old 10-05-2014, 01:39 PM
  #9  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Posts: 4,458
Likes: 0
Received 27 Likes on 20 Posts
Default

If a 7th-grade drop-out 'mechanic" at the marina can't get it right, how are we supposed to?

Wiring diagrams are your friends...
Old 10-05-2014, 06:13 PM
  #10  
Admirals Club Admiral's Club Member
 
Join Date: Aug 2009
Location: VA
Posts: 5,970
Received 436 Likes on 272 Posts
Default

Originally Posted by Buoy Scout View Post
...On breaker panels, where the switch is actually a breaker, then a buss bar is used to supply +12V to each breaker. and the proper sized wires run to each device. The buss bar (or daisy chained wire) must be capable of handling the sum of all possible loads and be no larger than the OCPD (over current protection device) upstream of it.
I anticipated that you might be wiring a breaker panel....(though I wasn't sure)

Originally Posted by Flymost1 View Post
You are misunderstanding where the "daisy chain" is. It is being done on the input side of the individual fuses / CB's. My positive inputs via a daisy chain to the inputs of the individual CB's for the individual components. This input comes from a master CB and switch. This allows for a master switch and CB to protect the panel, then individual CB's to protect each components circuit. Without this I would not have the option for a master switch, or if I did, then I would have to run 12 wires from the master to the inidividual CB's.
This is fine as long as the daisy chain wire is sized based on the feeder breaker that is protecting it (or larger). (should have said no smaller in the first quote above but I'm sure you get my drift...)
Old 10-05-2014, 08:26 PM
  #11  
Admirals Club Admiral's Club Member
 
Join Date: Oct 2007
Posts: 628
Received 118 Likes on 88 Posts
Default

Thanks Scout, Here is a pic of a simple switch panel similar to what I am rewiring. Still trying to find a way to avoid attaching 2 wires to one male quick disconnect via a double male to single female adapter. Surely someone has a better way to rewire this???
Attached Images  
Old 10-05-2014, 09:52 PM
  #12  
Admirals Club Admiral's Club Member
 
Join Date: Feb 2009
Location: Mason Neck, Va.
Posts: 962
Likes: 0
Received 22 Likes on 17 Posts
Default

Karl in NY

I may late to your thread. If I understand your first sentence correctly "daisy chaining" a row of switches. Then why not make (2) circuits feeding only half of your switch banks? That way you could split the load in half. I saw a new Paneltronics (8) switch and breaker panel done that way.
Old 10-06-2014, 05:08 AM
  #13  
Admirals Club Admiral's Club Member
 
Join Date: Aug 2009
Location: VA
Posts: 5,970
Received 436 Likes on 272 Posts
Default

Originally Posted by Flymost1 View Post
Thanks Scout, Here is a pic of a simple switch panel similar to what I am rewiring. Still trying to find a way to avoid attaching 2 wires to one male quick disconnect via a double male to single female adapter. Surely someone has a better way to rewire this???
two other methods--neither may apply to your panel--but might
1. use screw terminals rather than quick disconnects
2. Crimp both wires into a single terminal. Looks like that might be 10g wire anyway, so probably too big to do this.

This is why I like a separate fuse block supplied with the larger wire, then smaller wires running to each switch.

What is shown is perfectly acceptable, though.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.