Extech AC line splitter and Extech promotion at Amazon, 20-40% off - Page 1
Forum section: electronics / testgear

author: saturation
author_rank: Super Contributor
timestamp: October 02, 2015, 03:31:38 pm
content: If anyone is interested in Extech products, they have a sale ongoing this month at Amazon.I've always wanted one of these AC line splitters, also called AC line separator 15+ years ago when first released, but could never justify the $30-40 it was sold for. Over the years its increasingly become cheaper. However, I made a simple splitter with lamp cord and sockets on both ends that did the same thing for about $10.This line splitter is sold under many brands, some rebrand OEM others not, but all look roughly the same.With the Extech promotion, this unit sold for $13 delivered. Its much better made than my DIY and includes a 10x amplification loop for measuring smaller currents.There have been many criticisms of the OEM cheapo models over the years, most of which I've highlighted on the photos that this model fixes.In some production runs, the plugs and sockets would come loose, because they lacked mechanical mounts. In this Extech model they are solidly connected to the chassis if not screwed down.Line, neutral or ground would be miswired. In this Extech they are not miswired, but they use the wrong color coding for US system.Poor soldering, in this unit the soldering good.Safety certification. Confirmed via the UL website, this Extech unit is UL listed.You can get a Kill-a-watt, which is a built in power meter, voltmeter and ammeter, timer etc., that only reason to get this line splitter is to confirm the Kill-a-watt readings using a professional grade clamp meter.

author: commongrounder
author_rank: Frequent Contributor
timestamp: October 02, 2015, 05:19:48 pm
content: Interesting to see the inside of your splitter. I have one that looks very much like it, but with the Amprobe brand name. I am curious about something concerning the wire routing. If I am looking at your opened up photos correctly, the "hot" wire is the enameled one, and the black is neutral, and the red is ground. Crazy color scheme, but I guess it doesn't matter in this case. So, is the ground wire positioned where it was when you cracked it open? I wonder, because that would put it on the same side as the hot wire. This could lead to measurement errors (low) if there is significant ground current flowing, like if there was a hot-to-ground fault in the DUT. It seems like it should be on the neutral side so those currents would add and give a true total current flow. Also, I wonder which side of the 10X loop will give the most accurate readings. Depends on the actual number of turns, but I would think the "hot" wire side would be the best. Now I'm going to have to go open mine up and take a look!

author: saturation
author_rank: Super Contributor
timestamp: October 02, 2015, 06:16:16 pm
content: Hi commongrounder,Yes, the photos is as assembled by Extech. You raise all good points. I will test to see if there is a difference in the 10x side between the coils with and without the neutral [ here as 'black' wire] in close proximity to the coil.Good point about ground currents, the 'red' ground wire can easily be moved across so its parallel to the neutral wire instead of hot enamel wire.Please post your photos of the Amprobe version. That remains a premium priced model at between $20-35 so interested to see what's in it too.The cheapest 'clone' of this AC line splitter is Tekpower, which sells between $13-16. So this Extech version put in in line with the Tekpower pricing.FWIW today, if you price out a length of lamp cord, male and female sockets, you'll easily exceed the $13 price of the lowest priced AC line splitter. Even if miswired or badly assembled, its very easy to fix to perfection.The ABS plastic is thick enough for the required insulation and protection of CAT II 600V.Quote from: commongrounder on October 02, 2015, 05:19:48 pm

author: saturation
author_rank: Super Contributor
timestamp: October 21, 2015, 03:35:06 pm
content: FWIW I found no practical difference between each leg of splitter and that was using a Fluke 87V in series with the load to check actual currents. But this is within the limits of accuracy of the clamp meter, which was off between 3-10% relative to the Fluke measurements.