How to attach 10 gauge wire to a Grainger 3PDT switch?

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bigljd

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What's the best way to attach 10 gauge wire to this switch? Solder the wire directly to the posts, or try to find some 10g ring terminals with the small rings and try to find the tiny screws to screw the ring to the posts? Or something else?

There's 9 posts on this thing I'll have to wire to.

http://www.grainger.com/Grainger/NKK-Toggle-Switch-2TNZ7?Pid=search

Toggle-Switch-2TNZ6_AS01.JPG


Thanks
 
Use stranded wire (Not a solid conductor) and strip a small length of insulation off of the end of the wire. Push the wire through the terminal hole Shape it and then solder it in place. ONLY use radio solder for this. Do not use plumbing solder.
 
Use stranded wire (Not a solid conductor) and strip a small length of insulation off of the end of the wire. Push the wire through the terminal hole Shape it and then solder it in place. ONLY use radio solder for this. Do not use plumbing solder.

I'll be using stranded wire, but the 10 gauge wire is way too big to fit thru the terminal hole. I probably could solder it to the side of the terminal.

I've got some 60/40 rosin core solder from Radio Shack that says it's for PC work. Is that OK?
 
I just soldered a similar switch. I peeled back half of the strands and cut them about an 1/8" from the insulation. I threaded the other half through the hole and bent them back so the two bunches were touching. I then soldered.
 
I'll be using stranded wire, but the 10 gauge wire is way too big to fit thru the terminal hole. I probably could solder it to the side of the terminal.

I've got some 60/40 rosin core solder from Radio Shack that says it's for PC work. Is that OK?
It is possible to enlarge the hole a little to accept the wire using a Dremel. Or just place as many strands through as possible and solder all of it. The solder you reference is exactly the one you should use for the task.
 
I just soldered a similar switch. I peeled back half of the strands and cut them about an 1/8" from the insulation. I threaded the other half through the hole and bent them back so the two bunches were touching. I then soldered.
Exactly. Your description beat the pants off of what I was trying to say.

Thank You.!
 
I just soldered a similar switch. I peeled back half of the strands and cut them about an 1/8" from the insulation. I threaded the other half through the hole and bent them back so the two bunches were touching. I then soldered.

Thanks huntah and PJ. I'll give this way a try. I'm a bit rusty at soldering, but I should get lots of practice over the next couple weeks.

I've been playing around in Google sketch to try to map out my future panel. I think I like this layout best so far, but may change my mind again tomorrow.

Panel_Screenshot.jpg
 
Maybe a dumb observation but isn't 10g overkill for this switch? It can't handle the power that 10g does so why not downsize the wire to the switch?

Could be I just don't understand whats going on here.
 
Thanks huntah and PJ. I'll give this way a try. I'm a bit rusty at soldering, but I should get lots of practice over the next couple weeks.

I've been playing around in Google sketch to try to map out my future panel. I think I like this layout best so far, but may change my mind again tomorrow.

Panel_Screenshot.jpg

A little heat shrink can hide a lot of ugly solders.
 
bowhuntah said:
A little heat shrink can hide a lot of ugly solders.

Get the 'helping hands' set of adjustable gator clips to hold both pieces in position, a nice hot soldering iron, try to put most of the solder on the thing being soldered, practice finding a way to pill the iron off without making a solder point, and heat shrink.. 15W will not cut it for 10ga..
 
Maybe a dumb observation but isn't 10g overkill for this switch? It can't handle the power that 10g does so why not downsize the wire to the switch?

Could be I just don't understand whats going on here.


I'm basing my control panel on this P-J schematic (minus the timer):

wiringk.jpg



The load to the heating element will go thru the switch. P-J explains why the switch will work for this application here:

https://www.homebrewtalk.com/f170/controller-question-p-j-258594/#post3118433

Hope that helps
 
Agreed. I used a 25W iron.

I picked up an adjustable 20 to 50 watt iron from Radio Shack, so I should be good. I got a little practice today soldering the 2 resistors from the schematic together, and then soldered them to a fuse holder. I did a lot of soldering of electronic stuff when I was a kid, but it's been a long time.
 
Maybe a dumb observation but isn't 10g overkill for this switch? It can't handle the power that 10g does so why not downsize the wire to the switch?

+100 for the concern here. It looks to me like you are switching the heater elements through that switch, and I cannot believe it could possibly handle the current. Check that out carefully or you could create an overheat / fire condition.

DJG
 
+100 for the concern here. It looks to me like you are switching the heater elements through that switch, and I cannot believe it could possibly handle the current. Check that out carefully or you could create an overheat / fire condition.

DJG

That's not my concern at all. All I was saying was that you don't have any need to size wire above the load the switch can handle, therefore the soldering issue is much easier. If a wire can handle 30 amps @ 240v but the switch only handles 10amps and you put 30 amps on it the switch will burn up.
 
A bit more food for thought - crimped connections are often recommended over solder in high current applications. A fault (even momentary) could melt the solder and cause further harm.
 
So the ? is still out, why do you need 10 gauge wire going into a switch that can't handle the load a 10 gauge can handle?
 
Why are you bringing 10g wire to that switch? It can't handle the current that the wire can, so reducing to a smaller wire is prudent. If your system was assuming that high amperage will be routed through the switch, then you need to use a relay on this circuit so that the high amperage is not routed through the switch.
 
I would not use this switch for high current. If the switch was meant to handle 30A, It would not be an issue connecting 10ga wire to it.

I also do not agree with the (2) 1k 1W resistors. They will not handle the power dissipated. I used (4) 1k 1W resistors in series. This gives 30mA fault current and dissipates 3.6W. It will trip the GFCI and cannot burn up if the GFCI fails to trip. The fuse in the circuit serves no function as the current is limited by the resistors. The fuse really does no harm but I think it is a weak link in a critical circuit.

**edit** And while I'm at it, why is anyone fusing the PID at 1A? I contacted an Auber tech and he said the PID is internally protected and no additional fusing is necessary. The PID could be connected after the 10A fuse in the above drawing and save a few components. And why a 10A fuse?? No wire size is indicated on the drawings. I used a 15A fuse with #14ga wire to power my receptacles and PID.
 
How about using a terminal block rated for the 10 gauge wire, then run appropriate sized wire to your switches, PID, etc. from the block? Looks like you are wiring up a panel for an E-build, so this may be beneficial and keeps the inside of the control box looking clean.
 
That's not my concern at all. All I was saying was that you don't have any need to size wire above the load the switch can handle, therefore the soldering issue is much easier. If a wire can handle 30 amps @ 240v but the switch only handles 10amps and you put 30 amps on it the switch will burn up.

I am looking at the Grainger page and it says 25A at 125V AC, which is what the switch will really be carrying on each set of poles... (the center of the element will be at an imaginary neutral, since the phases are 180 degrees out. yes, if you had one side closed, and the other open, you could see a 240V potential)

Mainly, if the switch is not 'switched' under load, the extra arcing potential of 250VAC can never be present, so the 25A should be fine, as if there is no arcing potential, Amps are amps, be they at 125V or 250V. Yes, the 'rating' is not 100% correct, but if the circuit is protected by a 25A breaker, there should be no issues...
 
A bit more food for thought - crimped connections are often recommended over solder in high current applications. A fault (even momentary) could melt the solder and cause further harm.

That is why soldered connections should be mechanically secure (crimped) before soldering.. Unless there is a lot of tension on the wire, putting some or all strands through and then twisting is better, and will 99.9% be no issue when used with heat shrink, (but as said, not as good as crimping)
 
I am looking at the Grainger page and it says 25A at 125V AC, which is what the switch will really be carrying on each set of poles... (the center of the element will be at an imaginary neutral, since the phases are 180 degrees out. yes, if you had one side closed, and the other open, you could see a 240V potential)

Mainly, if the switch is not 'switched' under load, the extra arcing potential of 250VAC can never be present, so the 25A should be fine, as if there is no arcing potential, Amps are amps, be they at 125V or 250V. Yes, the 'rating' is not 100% correct, but if the circuit is protected by a 25A breaker, there should be no issues...

So, in essence, this switch is safe to use for this purpose due to the on-off-on configuration of the switch? Some of us are not educated "electrically" and need pretty basic help understanding the terminology.

Are there any better alternatives? Also, is placing half the wires through the hole on the switch and soldering back to itself appropriate? I ask these questions so that I don't have to start a bunch of other threads later on when I actually get to build my E-brewery
 
Grainger NKK-Toggle Switch 2TPE7 - DPDT Center Off
Contact Rating @ 125V (Amps) 30
Contact Rating @ 250V (Amps) 30


Grainger NKK-Toggle Switch 2TPF3 - 3PDT Center Off
Contact Rating @ 125V (Amps) 30
Contact Rating @ 250V (Amps) 30

Now check out the prices.
Oh and another thing for all the BS previously posted - How can they possibly be rated for 30A at both voltages?

I have no problems with using the switch that the OP had previously posted about (2TNZ7 - and it is on the parts list that you sent me yesterday P-J), so if this is the switch that will do the job, that is the way I will go. I am just trying to figure out the reasoning as to how the switch works/how it is applicable to the control panel. I was just curious if there were any other alternatives (better/worse/etc.).

Just trying to better myself through learning how these things work...
 
The switch in the first post is undersized!

Lets look at it from a wattage standpoint:

125V x 25A = 3125W
250V x 9A = 2250W

This is the max load the switch can safely handle. Either way, its too small to switch a 5500W load.

And we should be using the 250V rating for this application. L1 and L2 are both connected to the switch the arc across the contacts will be caused by 250V.
 
Another option is to wire a low power rated toggle switch to switch the 120VAC coil of this 2-pole contactor (which would be wired to the heating element) for a less expensive option:

Grainger 6GNZ2

That contactor is rated for 30A resistive load, no problem for a 5500W heater. There is a 240VAC and a 24VAC coil version of the contactor coil also.
 
Oh and another thing for all the BS previously posted - How can they possibly be rated for 30A at both voltages?

Because they are tested and certified at that voltage and current. Look around many switches are rated at the same current and multiple voltages. Took me a few seconds to find a few examples.
 
Another option is to wire a low power rated toggle switch to switch the 120VAC coil of this 2-pole contactor (which would be wired to the heating element) for a less expensive option:

Grainger 6GNZ2

That contactor is rated for 30A resistive load, no problem for a 5500W heater. There is a 240VAC and a 24VAC coil version of the contactor coil also.

That is what I would do. It's a lot easier to wire too. Your link seems to not work. Here is another example: http://www.elecdirect.com/product/77425d53-c906-400b-91a3-536bb59473e4.aspx
 
How can they possibly be rated for 30A at both voltages?

Interesting question. I would say it's because of the materials used for the contacts. That's a lot a power being fed through that switch.
 
The switch in the first post is undersized!

Lets look at it from a wattage standpoint:

125V x 25A = 3125W
250V x 9A = 2250W

This is the max load the switch can safely handle. Either way, its too small to switch a 5500W load.

And we should be using the 250V rating for this application. L1 and L2 are both connected to the switch the arc across the contacts will be caused by 250V.

That may be correct if the switch were consuming watts, but it is not...


the 250V rating is down to 9 because of 'arcing' when the switch closes.. but this switch is NOT switching 250V AC, on each pole, or you would have 500V AC total, but we do not... the two legs are in series.. 120V per leg, switch will be adequate...

Again, EACH leg is 120V...

and if you refrain from switching the toggle switch while the element is powered, you will have no problems for a looong time....


edit - arcing is worst when contacts 'open', not close...
 
Yikes, I leave my thread alone for a day and all h*ll breaks loose, LOL.

Since I'm this far down the rabbit hole I guess another $30 on a pair of contactors won't break the bank - I do like the idea of the load going thru contactors better than going thru the switch.
Since I haven't ordered my PID or SSR from Auberins yet, I'll probably add a couple of these onto an order this week:

http://www.auberins.com/index.php?main_page=product_info&cPath=2_31&products_id=129

So, if I'm thinking this thru correctly I'd run a lower amperage 120V thru the switch to trigger either the HLT contactor or the BK contactor. One hot lead on the contactor would come directly from the power source coming into the box, and the other hot lead would come from the SSR. The outputs on the contactors would go their respective heating elements.

Sound about right?

Thanks, and I hope you are going to stick around P-J. This place wouldn't be the same without you.

Larry
 
That may be correct if the switch were consuming watts, but it is not...


the 250V rating is down to 9 because of 'arcing' when the switch closes.. but this switch is NOT switching 250V AC, on each pole, or you would have 500V AC total, but we do not... the two legs are in series.. 120V per leg, switch will be adequate...

Again, EACH leg is 120V...

and if you refrain from switching the toggle switch while the element is powered, you will have no problems for a looong time....


edit - arcing is worst when contacts 'open', not close...

Yeah - I understand. Thanks.
 
Grainger NKK-Toggle Switch 2TPE7 - DPDT Center Off
Contact Rating @ 125V (Amps) 30
Contact Rating @ 250V (Amps) 30


Grainger NKK-Toggle Switch 2TPF3 - 3PDT Center Off
Contact Rating @ 125V (Amps) 30
Contact Rating @ 250V (Amps) 30

Now check out the prices.
Oh and another thing for all the BS previously posted - How can they possibly be rated for 30A at both voltages?

I think they can because the contactor does not 'see' the voltage once it is closed and working... you know, put a multimeter across the terminals of a fully loaded contactor and it will be *near* zero... power dissipated by the contactor is that voltage * current, and therefore affecting it's rating, is very small.. and the contactor has a much longer distance between the contacts when off, so 120/240 difference for arcing is negligible.. (well, that and it is actually rated for higher, but passed tests for both 120 and 240... :)


All that said,behind you 100%!


Mike
 
That may be correct if the switch were consuming watts, but it is not...


the 250V rating is down to 9 because of 'arcing' when the switch closes.. but this switch is NOT switching 250V AC, on each pole, or you would have 500V AC total, but we do not... the two legs are in series.. 120V per leg, switch will be adequate...

Again, EACH leg is 120V...

and if you refrain from switching the toggle switch while the element is powered, you will have no problems for a looong time....


edit - arcing is worst when contacts 'open', not close...

I am an electricity neophyte here, so sorry if I'm mistaken or adding fuel to the fire, (just trying to understand).

Voltage is always with reference to something, right? So 120V per leg is with reference to ground, (and/or neutral, since they're bonded back in the breaker panel).

In this circuit, however, each 120V leg is not feeding to ground. The circuit is between a +120V leg and a -120V leg, so the electric potential, (voltage), is +120 - (-120), or 240V. If this switch were switching FOUR 120V elements, (two per side of the switch), each of which were running at (+120/0), then there would be 120V at each contact. But whenever one leg is at +120, the other leg is at -120, (since they are 180° out of phase), so whenever one leg is at +120, the circuit is going from +120 to -120, a potential of 240V. So in terms of arcing, 240V is the maximum voltage that could be driving an arc across the contacts.

Now since you're switching, presumably, with zero current flow, (this is assuming you have your PID turned OFF, I assume?), it's not an issue, since we don't care about arcing, since there's no current flow because the SSR will be in it's off state.

But if you did switch it while the SSR was in an on state, wouldn't there be 240V on the contacts?
 
That may be correct if the switch were consuming watts, but it is not...


the 250V rating is down to 9 because of 'arcing' when the switch closes.. but this switch is NOT switching 250V AC, on each pole, or you would have 500V AC total, but we do not... the two legs are in series.. 120V per leg, switch will be adequate...

Again, EACH leg is 120V...

and if you refrain from switching the toggle switch while the element is powered, you will have no problems for a looong time....


edit - arcing is worst when contacts 'open', not close...

I never implied that a switch consumes "watts":confused: But simply applying Ohm's Law shows us how many watts the switch can handle. Are you arguing that it is too small?

When a switch closes it goes from infinite resistance to zero resistance. There is a point in between that is has some other value of resistance hence the arc. If you consider this a very high resistance so the element is negligable what is the voltage drop across the switch? It can be nothing but 240V. The switch needs to be rated for 250V.

You could probably wire this thing up with 14ga wire and have no problems for a "looong time" too but it's still not right.
 
I am an electricity neophyte here, so sorry if I'm mistaken or adding fuel to the fire, (just trying to understand).

Voltage is always with reference to something, right? So 120V per leg is with reference to ground, (and/or neutral, since they're bonded back in the breaker panel).

In this circuit, however, each 120V leg is not feeding to ground. The circuit is between a +120V leg and a -120V leg, so the electric potential, (voltage), is +120 - (-120), or 240V. If this switch were switching FOUR 120V elements, (two per side of the switch), each of which were running at (+120/0), then there would be 120V at each contact. But whenever one leg is at +120, the other leg is at -120, (since they are 180° out of phase), so whenever one leg is at +120, the circuit is going from +120 to -120, a potential of 240V. So in terms of arcing, 240V is the maximum voltage that could be driving an arc across the contacts.

Now since you're switching, presumably, with zero current flow, (this is assuming you have your PID turned OFF, I assume?), it's not an issue, since we don't care about arcing, since there's no current flow because the SSR will be in it's off state.

But if you did switch it while the SSR was in an on state, wouldn't there be 240V on the contacts?

Someone understands:mug:
 
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