Kiriakos DIY 50 Turn Current Coil 1A=50A current clamp calibration 5500A/COIL

[Kiriakos GR]

This time I got it seriously so to copy product design of FLUKE 50 Turn 5500A/COIL 

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Maximum Current 11A rms, continuous
AC / DC, 45-440 HZ

Uncertainty Due to Clamp Meter/Coil Interaction
± (0.25% of effective output + 0.5A), for toroidal-wound current clamps, such as the Fluke 80I and 80I-1000.
± (0.50% of effective output + 0.5A), for current clamps like the Fluke 80i-kw, 80i-400, 80i-410, 80i-500, 80i-1010, Fluke 31, Fluke 33, or equivalent.

Minimum Inside Diameter of Clamp Jaws  2.54 cm (1 in.)
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5500A/COIL this looks simple as product design, but anyone whom will dare to copy it, he will discover a pack of major challenges.
All of us we expect our work to end-up looking as the real thing.
Unfortunately for any one whom tried he failed, there is no a single success story recorded by google so far.   

The creation of the coil this requires a tube of 100,5 mm diameter.
The plastic base this should provide something that resembles to bird nest for the coil.
Every single coil turn this has to retain spacing from the next.
The final DIY product this should looking professionally made.

At my next post I will deliver how-to details, FLUKE this will hate more, but I do not care. 

[Kiriakos GR]

This story starts due my discovery that cheapest basic Plastic thermos flask, this can be usable as coil tube.
Plastic thermos flask diameter this found to be exact or a bit larger due only 10mm from the suggested 100,5 mm diameter.

Second in the row challenge this is you to keep coil turns stable under manual coil winding.
Paper tape (carton tape) of 50mm width, this is your best friend, at every 20 turns of coil, these must be anchored due outside with two layers of carton tape.
Best carton tape to use,  this is TESA Blue, because at removal this does not leave any glue residue.

Third challenge remove 50 turn coil for winding tube with this changing shape and or change in any way.
As you can see at my photographs bellow, again carton tape this is the solution.

Fourth challenge  this is finding a plastic base which this will become the housing of this project.
I am currently exploring best options for this step. 
 

Note:
Coil wire diameter of 1.5mm at 50 turns this is 270 grams of copper weight. 

[Kiriakos GR]

The battleground in action.   

All lovely geometrical shapes they need hard work so to be reproduced, especially when the object this is 3D.
So we have to start from basic mathematical calculations.

For example: we have 50 coil spirals that its one should have it own retention support slot at a cycle of 180 degree.
Basic calculation 180 degree divided to 50.
So far so good, but what is our diameter?
When the coil this gets formed at 180 degree shape, the known diameter of coil 110mm, this is not helpful.
Coil inner spirals they will unite, they will form one theoretical cylinder, while outer spirals they will simply be spaced from one to the next at 180 degree perimeter.

Careful observation of FLUKE 5500A/COIL this will deliver at expert eyes two information.     
a) The coil appear nested  (Submerged) 18~20mm
b) There a plastic round shape (180 Degree) (half moon) this is spirals spacer, which gets bolted on.
Therefore at some point, the coil this firstly gets submerged in to a nest at depth of 20mm, and spirals plastic spacer this gets attached afterwards.
 
Back to math calculations, the new challenge this contain three factors, that they should be calculated.
a) Coil diameter when this submerged by 20mm, and we looking about the distance at the surface when the coil becomes visible to us?
b) Coil diameter all 50 spirals as one = 25mm
c) Total coil distance from side to side when first and last spirals facing its other?

I do not have any 3D design software, and I am walking here between smallest possible trial and error.
And so, do not blindly try to copy, my calculations.

Here is the calculator that you are going to need.
https://www.omnicalculator.com/construction/angle-of-depression 

Coil housing...
Many years ago a good friend of my gave to me as a gift  one wooden box, 250x250mm this made due marine plywood.
This is small storage container for heavy hand tools.
I am using here it top cover alone, 26mm height and surface this is made of 3mm marine plywood.
(marine plywood properties: water resistant, higher mechanical strength = robust)

Spirals spacer...
According the science of geometry we are in need to draw 50 rad lines equally spaced.
We have to include in our thoughts the actual diameter of the copper wire  (1.5mm in my case).
Then we have to create 50 slots symmetrical to its other and of specific slot length (outer spiral holder).
 
My plan is of me to use fine jigsaw blade for metal and adjustable low speed at my power tool, so to create as many slots needed with extreme caution.

Bellow are photographs of my progress so far. 

[Kiriakos GR]

Houston, We Have a Problem! 

We have to add at our mathematical vocabulary and the word circumference.
I did find today one photograph of 5500A/COIL from a better view angle, it circumference (space occupied by spirals) this is greater number of 180 degree.
By the use of my own method at analyzing product dimensions due a picture, I have measure 226 Degree as total.

And therefore for now, I will pause any wood cutting activities, and I will return to R&D mode. 

 

[Kiriakos GR]

All right, that was fast speaking of required time for corrections.
If you own and use the right tools, you always achieve fast and accurate results.
https://www.ittsb.eu/forum/index.php?topic=1534.0

Coil circumference, this is now at 226 Degree as total. 

[Andrew-88]

I am sensing that you do not need this coil mainly for current clamp calibration.
But I am unable to read your complex mind either.   

[Kiriakos GR]

I am sensing that you do not need this coil mainly for current clamp calibration.
But I am unable to read your complex mind either.   

I have the expectation that this coil will boost 50Hz energy while it will significantly attenuate all frequencies over 400Hz (specific coil electrical bandwidth specifications).
This might proven to be the solution which I need, when using my Oscilloscope and current probe at measuring stand-by power of non resistive load.
So I am getting ready to explore this coil electrical behavior and or of any benefits, at another electrical application.

Even so, I will make this coil to be 100% exact copy of FLK 5500A/COIL, so to be also useful for current clamp calibration inspection.   
And regarding aesthetics it will look much better that this Russian project.

[Kiriakos GR]

Critical work completed. 

The Web-calculator did not helped much at giving me spacing numbers that work in my project.
So I did go 100% manual, lots of trial and error attempts at finding a spacing distance for Spirals spacer which works for me.
The outcome this is 49 slots.

I will call it as 99% success, and tomorrow I will move at the next step (no one he can imagine that I wasted ten hours just today).     
Aesthetics these will be taken care at the end... 

[Kiriakos GR]

Oh yes, this project moves ahead. 
Not red but rather equal to cherry this is the description speaking of color's palette.

No matter of how I feel about moving forwards, the paint drying time this is specific.
About gaining increased paint hardness, I will have to wait for 24 hours, before the next step. 

[overvolt]

No matter of how I feel about moving forwards, the paint drying time this is specific.
About gaining increased paint hardness, I will have to wait for 24 hours, before the next step. 

gloss spray paint always takes longer so this to achieve hardness.
You better leave it to get dry for the entire weekend. 
   

[Kiriakos GR]

No matter of how I feel about moving forwards, the paint drying time this is specific.
About gaining increased paint hardness, I will have to wait for 24 hours, before the next step. 

gloss spray paint always takes longer so this to achieve hardness.
You better leave it to get dry for the entire weekend. 
 

Identical pack of thoughts here too, I have not touch it yet. 
I was worry that it might be soft and that I will leave fingerprints and gave to it three days of drying time.

[Kiriakos GR]

This is not a Coil, its a WEAPON     

After finishing of my coil basic assembly, I could not wait any longer, I wanted to test it and discover the truth.
Did I do mistakes-less  work?

It is spot on as calibration accessory!!

I did my best to keep all spirals at equal diameter, the slots over the wood they did the trick about spacing.
Hot-glue at both sides.
And here is my a fully functional copy of  5500A/COIL.
Final touch at aesthetics this will follow.
 
Enjoy ..  the proofs.