Part II of the DMM story - Page 1
Forum section: electronics / general

author: PetrosA
author_rank: Frequent Contributor
timestamp: May 28, 2010, 04:14:33 am
content: So you might remember the Agilent U1211A clamp meter story and its pathetic 4 kOhm limit on the resistance scale... In the meantime, I contacted the seller (www.hensleytech.com) and got a great offer from them for a discount on a DMM and a few suggestions. Their handheld selection is small since they sort of specialize in benchtop meters, so I ended up not getting a DMM from them but I wanted to give them some praise and a plug here. Thanks Nate! I also emailed Agilent, but I guess they're still busy pushing my email around to various departments.My "dream" DMM is something along the lines of a Gossen Metrawatt, but that's way out of my budget for now, so I set myself a $150 (US) limit to keep myself in check.I had a few basic requirements which I felt pretty sure I could get in that price range:CAT IV to at least 600VTRMSAutorangingDecent accuracy for AC volts and Ohms (I wasn't even counting on GossenMetrawatt quality...)It had to be a name brand/no knock-offsIt had to work into the MOhms range to make up for my Agilent's weaknessesI'm actually amazed at how many DMMs there are out there for less than $150. What I ultimately found and ordered is a Greenlee DM-300. It's rated CAT IV up to 600V, has 1% accuracy on the AC volts range and reads up to 60 MOhms. Perfect! Even many of the more expensive models had up to 2.5% accuracy on the ACV range which would be useless for me. One of the things I need to do at times is check the incoming voltage from the utility. They have what's called a "Tariff" range and if the customer is getting something lower or higher than that range, I can call in the utility crew at no charge so it's important that I have a meter that's not going to be off by 6-10 volts when measuring 240V if I don't want to look like a smacked ass.The best part of the whole deal is that this meter costs $39 from Amazon. Yep. A CAT IV DMM from a reputable manufacturer for less than $50 bucks. I'll take it apart when I get it and do some photos if it looks interesting. I know it's not a meter for the electronics people out there, but I'm pretty sure I'm not the only electrician here so someone may get some use out of this post

author: EEVblog
author_rank: Unknown
timestamp: May 28, 2010, 05:00:33 am
content: HmmCan't say I've ever head of Greenlee.A TRMS CAT-IV DMM for $40 with a Lifetime Warranty does seen rather unusual, will be interesting to see what's inside it.It's just a basic DMM though, no fancy features, to get those you have to get the DM-330 for $128 which puts it in the same category as my $100 shootout meters.Big downside is they don't measure mA or uA, so no good for basic electronics use. But adequate for electrical/power use of course.Dave.

author: PetrosA
author_rank: Frequent Contributor
timestamp: May 28, 2010, 11:33:42 am
content: I guess I didn't think that the name Greenlee wouldn't necessarily rings bells for people outside N. America. They're one of the oldest companies here that make specialty tools for electricians and industry. While I'm not sure how long they've been selling test equipment (I'm guessing they started branding them in the 90s when they bought out a few electronics firms), they and Ideal are two of the big runners up to Fluke and together are the brands you'd be likely to see sold in elec. supply houses.You're right, it doesn't have the functionality that you'd need for electronics use and it certainly couldn't serve as my only meter either. But if it works as described, it should be a competent (and safe) second meter in addition to my Agilent for testing resistance as well as enabling me the simultaneous measurement of voltage and amps.At this point I should have all the basics covered and will be able to start planning for the next meters I need - a recording meter, a good megohmmeter and finally a scope for power quality analysis