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To noalox or to not noalox

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I have been reading up on the use of oxide inhibitors and how nowadays panel boards that are UL listed means they are for both copper and aluminum without the use of any oxidize inhibitor. However depending on the climate it is still recommended for example a place with high humidity and salt.

Why should we not use noalox when we don't have to? It still seems to be a good preventive thing to do.

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if outdoors and Alu .. i put no-alox on it period. i dont care what the specs say
however my poco does not put it on the underground service drops and i have yet to see a meter base burn out from that

so basically pay your money and take your choices
Our utility company requires us to use it with Aluminum. I mainly use it as an anti seize for the threads. That oxide inhibitor is like working with tar or silicone. I get it all over my hands and clothes.
 

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I have been reading up on the use of oxide inhibitors and how nowadays panel boards that are UL listed means they are for both copper and aluminum without the use of any oxidize inhibitor. However depending on the climate it is still recommended for example a place with high humidity and salt.

Why should we not use noalox when we don't have to? It still seems to be a good preventive thing to do.

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That is interesting to note that some antioxidants are petroleum based and should not be used. Otherwise it is okay to use it on copper or aluminum. Some engineers believe that ant-oxidants should always be used with both copper and aluminum
 
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Discussion Starter · #5 ·
if outdoors and Alu .. i put no-alox on it period. i dont care what the specs say
however my poco does not put it on the underground service drops and i have yet to see a meter base burn out from that

so basically pay your money and take your choices
I agree and think you might aswell put it on for what its worth. I think any arguments would be to do with a dry location where the noalox could interfere with the dielectric grease on breaker terminals...I donlt think that should be an issue though
Some engineers believe that ant-oxidants should always be used with both copper and aluminum
I have read that aswell...I maintain that it is worth putting on...especially if there are no downsides to doing it other than a small cost
 

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Chief Flunky
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The whole key to ANY electrical connection is that it’s already a gas tight connection.


The book is free if you hunt around for it. It came out in 1965 but it’s still valid.

When you squeeze the cable or busbar or even when a breaker closes the oxide layer is cracked. You get intimate metal-on-metal contact where the metal atoms actually make direct contact, the definition of a weld. More pressure smears the alpha spots out and forms additional ones. Any no-Alex in the joint gets pushed out. So the theory would be it makes little difference.

However these guys actually tested it and it seemed to help on joints that they purposely made loose. It roughly doubled the time to failure.


Interestingly it doesn’t make much difference in overheated joints from the charts in the study. And it still makes me wonder if it would perform the same on joints at normal tension (not overly loose).

I have not seen any other published studies and to me it creates more questions than answers.
 

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If you look at the AL H-taps and insulinks, you will see the no-lox already applied. Same goes with the compression lugs our utility uses.
Put the **** on, dont drown the connection.
This discussion will end up like the twist/no twist for marrettes. Or, ground up/dow
 

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I know GE loadcenters and asco transfer switches instruct you to use an oxide ohibiting compound on aluminum terminations.

I'll use it if it's convient on indoor aluminum terminations. I'll use it outdoor on aluminum mechanical lugs even if it's copper mainly just as a bit of lube on the threads of the screw. Some of the threads on lugs are terrible from the factory lately and will seize if they are dry.

I've been using Penn-Union Cual-Gel lately. It's grit free and similar to what's factory installed on the breaker stabs.
 

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I remember one member, I am thinking it was mxslick, who used to always bust into every other discussion in order to explain to the theater that we must take a wire brush to each and every stripped wire we terminate, be it stranded or solid, copper or aluminum, and brush the surface of the uninsulated connection end vigorously and then apply no alox to each and every termination we make, be it in a wirenut, around a device screw, or backstabbed into the profit holes.......... lol.......
 

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Chief Flunky
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I remember one member, I am thinking it was mxslick, who used to always bust into every other discussion in order to explain to the theater that we must take a wire brush to each and every stripped wire we terminate, be it stranded or solid, copper or aluminum, and brush the surface of the uninsulated connection end vigorously and then apply no alox to each and every termination we make, be it in a wirenut, around a device screw, or backstabbed into the profit holes.......... lol.......
The oxide layer isn’t very thick. If I get into making videos I’m thinking I set up a micro ohm meter and slowly crank up the pressure on a mechanical lug with the meter running to show what happens. The article I posted shows some difference but I wonder for instance is it more of a cleaning effect or the particles. If you use normal torques does it make a difference. Are you changing the bolt stretch. Lots of questions, no answers.
 

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I caution with applying it to threads. It changes the applied torque and you can strip aluminum lugs before you hit the spec.
I use to think the same but now the machining on some lugs is so bad that the threads are tight before the lug touches the wire. Also, as a past thread brought out, who maintains their torque wrenches out in the field, in the truck? Who has the wrench regularly calibrated? Now I am more concerned about the crappy lugs not seizing up. I know it is the wrong way of thinking but it is real life.
 

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I do like something on the threads - I wrench as much as I'm a sparky.

The caution is to hold back on the torque or you'll likely strip the aluminum lug or screw. BTDT.

Edit: various thread compounds (non electrical) reduce the required torque 15-40%... per some googling. I have yet to find a rating for noalox type stuff.
 

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In a previous thread someone, I don't remember who, suggested a particular type of terminal would do away with the need for torque measuring tools. Can anyone remind me of what type of terminal that is.

Tom Horne
 

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I caution with applying it to threads. It changes the applied torque and you can strip aluminum lugs before you hit the spec.
I agree. Always use it when the instructions call for it, of course. I try not to slop so much on that it gets on the threads. In wet locations flooding the voids with the gel keeps water out, but in dry locations, anything more than just a coating is wasted and it might get in places where it causes trouble.
In a previous thread someone, I don't remember who, suggested a particular type of terminal would do away with the need for torque measuring tools. Can anyone remind me of what type of terminal that is.

Tom Horne
Was it the use of a Bellville (conical) washer?
 

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I remember one member, I am thinking it was mxslick, who used to always bust into every other discussion in order to explain to the theater that we must take a wire brush to each and every stripped wire we terminate, be it stranded or solid, copper or aluminum, and brush the surface of the uninsulated connection end vigorously and then apply no alox to each and every termination we make, be it in a wirenut, around a device screw, or backstabbed into the profit holes.......... lol.......
I would go one step further and state the following. If you do not pre brush, you are doing it wrong and shouldn't even bother. I have been through the whole subject way too many times. I haven't found a wire manufacturer that requires it or a panelboard manufacturer that requires it. I did however find an obscure reference to an "inhibitor" in the installation manual of an ASCO transfer switch. That's it, that's all I can find.
If I were in the field standing an inspection, I would be just fine arguing with an inspector. Im not in the field meeting inspectors anymore so, to avoid problems, we goop all aluminum wire terminations. The inspectors like to see it so, screw it.
 

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I don't think it is as required with newer aluminum alloy 8000 wire because it doesn't have the thermal expansion rates of the old 1350 stuff. This means that once the connection is made (properly), it typically will stay tight and not allow oxidation to creep in. I feel it doesn't actually harm anything to protect the exposed aluminum, so i still use it on any stranded connections.
 

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I would go one step further and state the following. If you do not pre brush, you are doing it wrong and shouldn't even bother. I have been through the whole subject way too many times. I haven't found a wire manufacturer that requires it or a panelboard manufacturer that requires it. I did however find an obscure reference to an "inhibitor" in the installation manual of an ASCO transfer switch. That's it, that's all I can find.
If I were in the field standing an inspection, I would be just fine arguing with an inspector. Im not in the field meeting inspectors anymore so, to avoid problems, we goop all aluminum wire terminations. The inspectors like to see it so, screw it.
If Miami got anywhere near the same size waves as we have you would absolutely know why you are slathering it onto the aluminum wires. Sooo much salt gets airborne here during winter it's not funny.
 

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Today I was a bad bad boy cause I used some #2 SER cable inside conduit for a hookup to an exterior panel. The reason I was so bad was cause I used no-alox on the aluminum terminations, and I also greased up that bare ground aluminum conductor pretty good inside the panel board.

I hope I can continue to member here , but I also know this is a huge infraction.
 
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