Author Topic: Test leads for power supply, make or buy?  (Read 16106 times)

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Offline nowlan

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Re: Test leads for power supply, make or buy?
« Reply #25 on: April 24, 2015, 03:37:43 pm »
Slightly off topic:
I am looking for shrouded 4mm plugs. I want to make a a box similar to this.

I dont trust the stackable connectors with mains voltage. I have seen a few brands and styles, by Mueller and silvertronic. Not sure if I want 90' for strain relief. Unfortunately they seem to come in packs of 2 or 5.
 

Online Jeroen3

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Re: Test leads for power supply, make or buy?
« Reply #26 on: April 24, 2015, 05:12:04 pm »
Try the SLS 10, they fit regular 4mm banana plugs, while still keeping it shrouded.
http://tinyurl.com/nk3ptnj
 

Offline rx8pilot

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Re: Test leads for power supply, make or buy?
« Reply #27 on: April 24, 2015, 05:15:37 pm »
OTOH, I'm not that big on the DUAL kind of banana plugs because it limits you flexibility to connect ONLY to the proper-spaced pair.

This is my favorite kind of Pomona banana plug....



Those Pomona's are my go-to choice and they have be re-purposed dozens of times. Usually keep 15-20 on hand to rig up a test configuration. The dual plugs have been handy since I built a custom IO panel for my HP power supplies and electronic loads. The singles get used for meters and the duals get used for power.

Either way, as much as I don't like making them, I would not do it any other way. I have the perfect compliment of leads for the type of work I do and I have enough spare parts to make anything on the fly.

Factory400 - the worlds smallest factory. https://www.youtube.com/c/Factory400
 

Offline john_p_wi

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Re: Test leads for power supply, make or buy?
« Reply #28 on: April 24, 2015, 05:28:02 pm »
Can you comment on the cheaper banana plugs such as these?  Will these with good wires and strong alligator or grabbers work in you opinion?
http://www.amazon.com/Hosa-Technology-BNA100-Banana-Connector/dp/B000068OAY/ref=sr_1_2?s=electronics&ie=UTF8&qid=1429841979&sr=1-2&keywords=dual+banana+plug
The traditional design with the solid metal core and the four length-wise springs are the prefered design. Those newer things with plastic parts and dodgy spring design are questionable IME.

OTOH, I'm not that big on the DUAL kind of banana plugs because it limits you flexibility to connect ONLY to the proper-spaced pair.

This is my favorite kind of Pomona banana plug....



^^^ Yes ^^^

If you build your own, use these Pomona or similar Pomona.  On some of the cheap knock offs, the "springs" are higher up towards the wire connection point - thusly they do not make good contact towards the tip.  This is important IF the mating jack is somewhat shallow, I noticed it with a BK 2709 DMM, but not a problem with Flukes.

I hate cheap crap that doesn't work.
 

Offline rx8pilot

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Re: Test leads for power supply, make or buy?
« Reply #29 on: April 24, 2015, 05:48:52 pm »
I hate cheap crap that doesn't work.

Saving money is an art. Buying cheap stuff is often the most expensive option.
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Offline broderp

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Re: Test leads for power supply, make or buy?
« Reply #30 on: April 24, 2015, 07:47:09 pm »
This is my favorite kind of Pomona banana plug....

I agree, I like Pomona, but they are very pricey.  They would be on my short list if money was no object.   I like these:
http://www.amazon.com/Pomona-3786-C-36-Minigrabber-Multi-Stacking-Double/dp/B00COC9U1C/ref=sr_1_11?ie=UTF8&qid=1429904501&sr=8-11&keywords=pomona+banana+plug

But MAN,  this seems like a total rip off.. :o

Even the connectors you like are pricey for just the banana end:
http://www.amazon.com/Pomona-1825-02-Solderless-Stackup-Banana/dp/B00COBUR2Y/ref=sr_1_1?ie=UTF8&qid=1429904501&sr=8-1&keywords=pomona+banana+plug

I know, you get what you pay for, but I don't always believe cost equals the best quality... ;)
« Last Edit: April 24, 2015, 07:50:11 pm by broderp »
 

Offline bookaboo

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Re: Test leads for power supply, make or buy?
« Reply #31 on: April 24, 2015, 08:27:50 pm »
Yeah it's a pain when the power supply sticks the earthing jack right in the middle.
Or if you want to take the power connection and temporarily ground it to discharge the circuit, etc.

Quote
Pomona 1825 series.  I like to keep those around also.  Solid contact, stacking design, set-screw, and very re-useable.
I really prefer the kind like that with the FIXED springs.


The kind with the loose, rotating spring just adds another layer of (not very good) pressure contact to the circuit, and I don't really like that because it increases the contact resistance and reduces reliability.


Is that screw on the side connected to the pin?
 

Offline broderp

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Re: Test leads for power supply, make or buy?
« Reply #32 on: April 24, 2015, 08:48:12 pm »
Quote
Is that screw on the side connected to the pin?

In my limited experience, mostly with fairly cheap banana's YES, the screw on the side is what you use to secure the wire. The metal part of the pin is usually all one part. 
 

Offline Richard Crowley

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Re: Test leads for power supply, make or buy?
« Reply #33 on: April 24, 2015, 08:51:24 pm »
Is that screw on the side connected to the pin?
Yes. I wasn't trying to endorse those designs, only illustrate the fixed longitudinal spring design vs. the floating round spring.

If I had to use those with a screw in the side, I would probably put heat-shrink tubing over it after assembly.
And remember to never use them for high voltages.
 

Offline Dave Turner

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Re: Test leads for power supply, make or buy?
« Reply #34 on: April 25, 2015, 02:22:38 am »
From a safety viewpoint I dislike exposed connections, grub/set screws etc. and prefer shrouded connectors.

Yes I've got leads that don't comply with my preferences and when testing much is exposed to careless hands.

Without being too paranoid I prefer to avoid accidental shorts even with low power kit. Perhaps it's my own clumsiness but I also prefer to use the shortest probes/connectors I can which place the least strain on the parts connected to.

 

Offline john_p_wi

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Re: Test leads for power supply, make or buy?
« Reply #35 on: April 25, 2015, 05:06:33 am »
This is my favorite kind of Pomona banana plug....

I agree, I like Pomona, but they are very pricey.  They would be on my short list if money was no object.   I like these:
http://www.amazon.com/Pomona-3786-C-36-Minigrabber-Multi-Stacking-Double/dp/B00COC9U1C/ref=sr_1_11?ie=UTF8&qid=1429904501&sr=8-11&keywords=pomona+banana+plug

But MAN,  this seems like a total rip off.. :o

Even the connectors you like are pricey for just the banana end:
http://www.amazon.com/Pomona-1825-02-Solderless-Stackup-Banana/dp/B00COBUR2Y/ref=sr_1_1?ie=UTF8&qid=1429904501&sr=8-1&keywords=pomona+banana+plug

I know, you get what you pay for, but I don't always believe cost equals the best quality... ;)

Man whom ever set those Amazon prices is on crack.  As I mentioned before, check out Mouser:

Buck 85 for singles all day long:

http://www.mouser.com/ProductDetail/Pomona-Electronics/1825-2/?qs=sGAEpiMZZMsQWb9Zho8SKjolHJYGwbfH
« Last Edit: April 25, 2015, 05:08:07 am by john_p_wi »
 

Offline broderp

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Re: Test leads for power supply, make or buy?
« Reply #36 on: April 25, 2015, 03:12:58 pm »

Man whom ever set those Amazon prices is on crack.  As I mentioned before, check out Mouser:

Buck 85 for singles all day long:

http://www.mouser.com/ProductDetail/Pomona-Electronics/1825-2/?qs=sGAEpiMZZMsQWb9Zho8SKjolHJYGwbfH

Perhaps not all Pomona banana plugs are equal?
http://www.mouser.com/ProductDetail/Pomona-Electronics/1825-02/?qs=sGAEpiMZZMtW7Xd10NdmuJ0hw%2fJ5i2UGkOyIZt8O6Ao%3d

I'll see if I can find them in red as well.  The data sheet states the "-" number (1825-X) is the color.  2 is red, but the image shows black.  Not a big deal I just want to be sure. 

Thanks for showing me an alternate source.  Hope shipping wont be hateful ;)

EDIT: Never mind, the link above is for TWO, one red and one black.  ::)

EDIT: Cheapest shipping option is $5  Six pair would break down to costing about $2.37 each.  STILL MUCH CHEAPER THAN AMAZON. lol  ;)

I've been communicating with Frankie via email.  If he can put together a reasonable priced option to do what I need, I think I will try his leads out first. 

If I need to make them, I will get these Pomona's and start to research wire and clips and grabbers for the other end.  Just a lot of work I'd rather not do at this point.  :-\
« Last Edit: April 25, 2015, 03:21:41 pm by broderp »
 

Offline nanofrog

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Re: Test leads for power supply, make or buy?
« Reply #37 on: April 25, 2015, 09:47:22 pm »
I'll see if I can find them in red as well.  The data sheet states the "-" number (1825-X) is the color.  2 is red, but the image shows black.  Not a big deal I just want to be sure.
If the P/N is correct as per the color code per what you're after on singles (1825-1 for BLK or 1825-2 for RED), you'll get the correct color you're after.  :-+

Thanks for showing me an alternate source.  Hope shipping wont be hateful ;)
They'll charge you the real rate they pay (same for other mainstream component distributors), so figure ~$7.00 or so for a handful of banana plugs. Add enough to bring your order up to say a $50+ order, and the shipping is much cheaper per part (i.e. shipping may still only come in at $8 - $9 for ~4x the order cost of just the banana plugs).
 

Offline robrenz

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Re: Test leads for power supply, make or buy?
« Reply #38 on: April 26, 2015, 12:38:02 am »
If I need to make them, I will get these Pomona's and start to research wire and clips and grabbers for the other end.  Just a lot of work I'd rather not do at this point.  :-\

I listed links for excellent Pomona wire and grabbers in post 21.  I realize it may be more money than you want to spend right now. Those parts listed turn out to be $4.32 for a 36" lead with Pomona wire and grabbers.
« Last Edit: April 26, 2015, 12:43:48 am by robrenz »
 

Offline broderp

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Re: Test leads for power supply, make or buy?
« Reply #39 on: April 28, 2015, 01:09:01 am »
If I need to make them, I will get these Pomona's and start to research wire and clips and grabbers for the other end.  Just a lot of work I'd rather not do at this point.  :-\

I listed links for excellent Pomona wire and grabbers in post 21.  I realize it may be more money than you want to spend right now. Those parts listed turn out to be $4.32 for a 36" lead with Pomona wire and grabbers.

I've bookmarked that post for future reference. Thanks!  :)
 


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