IEC Wiring on Nigel's Speed Controller

jmathers

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I'm building a speed controller for my Lenco (Nigel's Speed Controller). I always seem to get stuck on wiring the IEC, fuse, and switch. Fortunately Nigel has written detailed instructions. Unfortunately, I'm not using the combo IEC part he recommends since that would place my power on/off switch in the back and difficult to reach. Instead I'm using independent IEC, separate fuse, and front-mounted toggle switch.

Here's how he recommends wiring the combo IEC, switch, and fuse unit (wires at the top go out to a supply transformer - brown and grey are on the hot/live side of the switch):

nigeliec.jpg

Here's a drawing of what I thought would be the right way to hook up separate IEC, fuse, and switch:

iecdraft.jpg

I've been told this is incorrect however since it results in a "dead short." But I can't really see how it's any different from the top picture.

Any advice on how to wire this up correctly? Can't wrap my head around it.

For those interested, Nigel's instructions for this are here.
 
Thank you. And thanks for taking the time to make a drawing. That's exactly what @Wntrmute2 said to do.

Is the pictured (not the hand drawn one) hookup above based on Nigel's instructions incorrect then? I should note that the actual combo IEC that Nigel uses has two pairs of lugs at the switch end. The one I bought has just the pair.
 
I want to look up the datasheet so it doesn't matter who has stock. Just want to know the exact part number he's using for his instructions.
 
Here's a pic from the instructions (switch to the left, fuse middle, IEC right):

1614975072554.png
 
Ok, got it. So take his instruction and draw them out as a schematic like I did.
 
I have to run. Click the spoiler button below to see my schematic after you've done yours.

It's a double pole switch:

IMG_6329.jpeg
 
Ok. If you draw the path the electricity will take on that, you get a dead short. Secondarily the transformer primaries as drawn will not work as there is no path for the electricity to flow.

1614976854185.png
 
Ah, I missed the double pole switch. That's the trouble I'm having since I have a single pole.

So I guess I'll have to add a tag strip in my chassis to get the wiring from the switch over to the primary transformer.

And yes, I see the mistake in my drawing of the primary transformer connections. Brown/White should be connected to the other side of the switch. And as you showed earlier the N connection goes straight to the Blue/Purple TX connections.

Thanks so much for the help. It's much appreciated.
 
I finally see it! Hard to describe but for one thing the two units you've shown are not the same. One unit has 5 connections and one has 7. On the first pic throwing the switch will connect the two legs of the power causing a short. In the second, the switch breaks both legs and current flows "down" the switch in parallel.
 
BLU/GRY is one primary, and PPL/BRN (is mistakenly labeled it WHT on my first drawing) is the other. Those two in parallel.

** ^ Edited to reflect actual winding color codes from datasheet.

So I guess I'll have to add a tag strip in my chassis to get the wiring from the switch over to the primary transformer.

I don't understand why this would be needed?
 
How it should be wired for the parts you have, just to make sure we're on the same page.

IMG_6330.jpeg
 
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You don't need a tag strip. I included it in the diagram I sent you so you wouldnet be trying to jam too many wires into the small holes on the switch.
 
How it should be wired for the parts you have, must to make sure we're on the same page.

Yep, I have it. Crystal clear now.

I guess I won't need the tag strip. Since blue, purple, brown and gray are all bundled together I was thinking that if I connected the brown and gray to the front of the chassis that I'd need to attach some extra wire to blue and purple to reach the IEC in the rear. But I've just tested it and both pairs will attach (just!) to front and to rear.
 
I think the difference is that Nigel's combo inlet/fuse/switch has a dual pole, single throw switch -- which is essentially two simple on/off switches bundled together. So picture two switches: one switches hot (L), the other switches neutral (N) -- both at the same time.

As jp points out above, you can't connect both L and N to the same switch/pole b/c it results in a dead short that will instantly trip your panel breaker and blow your fuse.

I'm not sure why the design calls for both hot and neutral to be switched -- I've only ever switched hot. If you want to implement the dual switch approach, you'll need a DPST switch (dual pole single throw), or a DPDT and leave the extra throws empty.

Otherwise, I'd follow jp's schematic using a spst or spdt switch. If using an spdt, only one of the two outside prongs (throws) gets connected - the other is left empty.

cheers, Derek
 
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