Quick connect for testing of 480 VAC device? - Page 1
Forum section: electronics / general

author: martincho
author_rank: Contributor
timestamp: March 08, 2022, 10:51:56 pm
content: I have to test over 100 units of a device that runs at 480 VAC. The device will have a stripped 3-conductor cable (L, N, GND) coming out of it, no connector. Power is minimal, less than 1/2 A.I am looking to build/buy a simple rig to do this with minimal fuss. These are my specs at the moment:- Power switch for safety- Easy plug in and outI will probably add AC current and voltage panel meters.My current concept is to use a NEMA L8-20 twist-lock plug with a short length of flexible cord and Wago 2-pin lever connectors on the end. Something like this:https://www.mcmaster.com/7162K65/https://www.wago.com/us/wire-splicing-connectors/inline-splicing-connector-with-lever/p/221-2401Procedure:- Connect L, N and GND to the twist-lock connector: Flip all three levers; push wires in; flip levers down- Connect twist-lock to test rig- Flip the switch and go through test procedure- At the end of the test, turn off, reverse procedure to disconnectIn other words, three layers of safety: 1- Power switch; 2- Twist-lock is disconnected while attaching to device; 3- Wago splicing connectorsIs there a better approach? Both speed and safety are important.Thanks,-Martin

author: Monkeh
author_rank: Super Contributor
timestamp: March 08, 2022, 11:00:04 pm
content: That's not L/N, but anyway..https://www.cliffuk.co.uk/products/tools/quicktestqt3.pdf

author: bdunham7
author_rank: Super Contributor
timestamp: March 08, 2022, 11:04:36 pm
content: That sounds reasonable provided every element of your test rig can withstand the available fault current. You might consider adding fuses to both inputs just to be safe.https://www.grainger.com/product/1CP25?ef_id=Cj0KCQiAmpyRBhC-ARIsABs2EArTZctoBhGm81GccT872Nli0BxxhjMdQq5Apb_ujYhx1TVwzfjz76AaAtzOEALw_wcB:G:s&s_kwcid=AL!2966!3!264955915673!!!g!461787465034!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=Cj0KCQiAmpyRBhC-ARIsABs2EArTZctoBhGm81GccT872Nli0BxxhjMdQq5Apb_ujYhx1TVwzfjz76AaAtzOEALw_wcB&gclsrc=aw.ds

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 08, 2022, 11:08:10 pm
content: How about alligator clips secured to an enclosure with a transformer to provide the 480V from 120V and a cover that turns on the power when it closes over the alligator clips?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 08, 2022, 11:09:31 pm
content: If you want to do it properly, put the connectors under a lid of some sort that switches off power when lifted.Or use something specifically designed for this ( though not 480v it would probably be fine, apart from the neon)https://cpc.farnell.com/cliff-electronic-components/cl-1850/quick-test-block-no-lead/dp/PL16023

author: martincho
author_rank: Contributor
timestamp: March 09, 2022, 12:41:47 am
content: The Cliff Quick Test rig seems like the right solution. Now that it was brought-up here I vaguely remember seeing it on YouTube somewhere. Probably an EEVblog video!Thanks,-Martin

author: martincho
author_rank: Contributor
timestamp: March 09, 2022, 12:56:52 am
content: I should add that the Cliff box isn't rated for 480 VAC but it should be fine for a low current (1/2 amp) test at that voltage.The only thing missing that could be nice are voltage and current meters. That's easy to add using panel meters.I just picked-up 5 of them.Thanks again,-Martin

author: Monkeh
author_rank: Super Contributor
timestamp: March 09, 2022, 12:59:02 am
content: The three-phase version is rated for 440VAC which is close enough.

author: martincho
author_rank: Contributor
timestamp: March 09, 2022, 02:58:47 am
content: Quote from: Monkeh on March 09, 2022, 12:59:02 amFair point.I'll contact them and see what they have to say. The connection clips and switch look the same. I suspect the light and fuses they have in the 240 V model might be the rating drivers.Thanks,-Martin

author: amyk
author_rank: Super Contributor
timestamp: March 09, 2022, 04:50:11 am
content: Quote from: martincho on March 09, 2022, 12:41:47 amProbably bigclivedotcom - I don't think I've seen one on EEVBlog.

author: james_s
author_rank: Super Contributor
timestamp: March 09, 2022, 05:31:03 am
content: Yeah Big Clive did a video on that, they're really slick devices.I usually use a suicide cord that has a plug on one end and alligator clips on the other. It's definitely not the safest way to go but so far I'm still here. Mostly 120V but I've used a similar cord on 240V and 480V 3 phase.

author: SeanB
author_rank: Super Contributor
timestamp: March 09, 2022, 07:49:10 am
content: Have had a few, from bare wire ends, to ones with spade connectors on the ends, but insulated ones, so it was safer.

author: SmallCog
author_rank: Frequent Contributor
timestamp: March 09, 2022, 10:24:41 am
content: For years I’ve had a suicide lead with a bit of chocolate block on the end for bare wired stuffhttps://www.jaycar.com.au/10-amp-12-way-screw-terminal-strip/p/HM3196?gclid=CjwKCAiAvaGRBhBlEiwAiY-yMIOJxWo5UEQWH90ickL622aYrBZMNjlptpCuaJeumhOfx8uLdKjQhBoC63kQAvD_BwE] https://www.jaycar.com.au/10-amp-12-way-screw-terminal-strip/p/HM3196?gclid=CjwKCAiAvaGRBhBlEiwAiY-yMIOJxWo5UEQWH90ickL622aYrBZMNjlptpCuaJeumhOfx8uLdKjQhBoC63kQAvD_BwEI felt quite posh when I splashed a dollar on a wago style lever lock connectors for the end of ithttps://www.altronics.com.au/p/p2246-3x3-way-joiner-splicing-terminal-block/] https://www.altronics.com.au/p/p2246-3x3-way-joiner-splicing-terminal-block/Good choice on the quick test it’s on my Wishlist. Should leave my suicide leads laying around next time we have a safety audit…

author: Monkeh
author_rank: Super Contributor
timestamp: March 09, 2022, 04:42:13 pm
content: Quote from: martincho on March 09, 2022, 02:58:47 amThe BS1362 fuse will indeed be rated at 250V, and the neon between line and neutral will not particularly enjoy 400V+. The three-phase neons will be to neutral so you'd only expose them to 277VAC, which will slightly shorten their lives.. in a duty-cycle-limited test appliance. I'm not sure what fuses they have specifically, but they appear to be 6.35x32mm (1/4" x 1-1/4") and are most likely rated 600VAC.

author: martincho
author_rank: Contributor
timestamp: March 10, 2022, 01:23:00 am
content: I heard back from the company. The contacts are the same on the 230 and 440 V versions. They said the neon lamp is likely to blow out at 480.I think I'll get one and run a torture test at 480 and see how much trouble I can get into. I like the design. It's good to know the contacts are not an issue. The rest is manageable.Of course, they disclaim any responsibility when used outside of specifications, which is fine with me.

author: Zero999
author_rank: Super Contributor
timestamp: March 13, 2022, 10:43:55 am
content: Quote from: martincho on March 10, 2022, 01:23:00 amIt should be fine at 480V. Increase the resistor value, to protect the neon lamp.