DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Electrical (
-   -   Slimline Vs. Tandem Vs. Double Pole (

turd hurder 06-23-2008 12:32 AM

Slimline Vs. Tandem Vs. Double Pole
I am trying to understand what the exact uses are here. From what I gather slimline and tandem breakers accomplish the same thing. Is this correct? Now double pole breakers connect to both hot buses to make a 240v circuit, right? What I am wondering is why would a double pole circuit breaker be used to wire 120v circuits? Thanks for your help in advance


frenchelectrican 06-23-2008 03:00 AM

The slimline useally described as half inch breaker [ very common found with GE breakers but also it will be show up with other manufacters as well but kinda rare nowdays expect Homline breaker they used have that for a while]

The tandem breaker is useally described as two single pole breaker in a single pole format
But becarefull some of the tandem breakers can be actally a true double pole [ I know for sure GE breakers do have this feature ] and if not mounted right you will end up a tons of headache why not getting any 240 volts on that circuit breaker ]

The double pole breaker { AKA two pole } is a true two pole breaker which it will turn off both hot conductors with common handle and it can be used either 120 or 240 volt circuits.

However if your area is on 2008 code cycle this part it will be manitory i will explain in a sec .,,

If you heard the term " Multiwire Branch circuit " ? If so great.,,,

If not what it mean that circuit will have two circuit with one cable like example 12-3 W/G [ black , red , white and ground { useally bare or green depending on cable itself }] black and white on circuit #1 while red and white is circuit #2 so., Circuit #1 is 120v while Circuit #2 is 120v also but get two hot conductor you will end up 240 volts however.,, there is one golden rules with any MWBC [ multiwire branch circuit ] never lift or disconnect the netual wire while either or both circuit is engerized the result if you do lift you will loose the netural and anything still hook up on 120v will become 240v and kiss your gimzo goodbye with magic smoke.

That one reason why the code did change on this part on both resdential and commercal location.

The other thing about duplex or tandem breaker is that with the MWBC you have to make sure you land in right spot other wise if you got this in wrong spot you will really overloaded the netual wire it will become addtive like example

tandem breaker [ upper handle ] is 20 amp while lower breaker handle is 20 also and when you land it wrong spot it will add up fast 20 + 20 = 40 amp on netual wire.

I will let Stubbie make a drawing if he have time so make it clear on the sisuation.


All times are GMT -5. The time now is 11:37 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1