DMMCheck Plus - Page 1
Forum section: electronics / testgear

author: Leuams
author_rank: Contributor
timestamp: August 30, 2014, 11:22:55 am
content: I'm looking for a reference to check a HP 3466A digital multimeter I bought on eBay and am fixing up. I was searching for old voltage standards equipment on eBay and came across this company which also sells from their own website.http://www.voltagestandard.com/DMMCheck_Plus.phpI was wondering if anyone has any experience with this item or company.I know it is not super precise or accurate but I don't need that to get a functional multimeter and to have a standard to compare my used equipment with. Plus I can't justify buying a voltage standard for $300 plus and it only does one thing.

author: all_repair
author_rank: Frequent Contributor
timestamp: August 30, 2014, 11:41:55 am
content: The deal is better now. When I bought, there was no traceable calibration data. I would also buy the enclosure if it was available. It is difficult to store without enclosure.

author: Fsck
author_rank: Super Contributor
timestamp: August 30, 2014, 11:51:32 am
content: I have one and it has served me well, works well for checking newly acquired gear.the new turret contact points + enclosure make it an even better product. there's a decent number of people who own a dmmcheck on these forums and they'll probably agree with its usefulness.

author: ModemHead
author_rank: Frequent Contributor
timestamp: August 30, 2014, 12:00:24 pm
content: Very useful and cost-effective for the hobbyist. And Doug at voltagestandard.com is a nice guy and very customer-oriented.Search this forum for "dmmcheck", there are many references.

author: Leuams
author_rank: Contributor
timestamp: August 30, 2014, 12:15:14 pm
content: Thanks all. I did a quick search before posting but I must have not used the right keywords. I'll be ordering one soon.

author: retiredcaps
author_rank: Super Contributor
timestamp: August 30, 2014, 06:45:23 pm
content: Martin did a review.

author: Lightages
author_rank: Unknown
timestamp: August 30, 2014, 06:53:31 pm
content: Without any doubt, the Voltage Standard references are a good deal, reliable, and backed by a good man with a good reputation. Don't hesitate, buy one!

author: PedroDaGr8
author_rank: Super Contributor
timestamp: August 30, 2014, 09:20:35 pm
content: I picked up one on here used for a great price a while back. It has come in handy several times, well worth the cost.

author: edavid
author_rank: Super Contributor
timestamp: August 30, 2014, 10:09:24 pm
content: I'm sure it's a good product, but I would have a hard time spending $40 on a standard to check a $20 meter

author: SeanB
author_rank: Super Contributor
timestamp: August 31, 2014, 07:34:12 am
content: But with the $40 standard you will have better confidence on the $20 meter reading, and when you do get a better meter it will help with confidence there as well.

author: Rick Law
author_rank: Super Contributor
timestamp: August 31, 2014, 08:10:29 am
content: Quote from: all_repair on August 30, 2014, 11:41:55 amAbsolutely get the enclosure. A bit more expensive but well worth it.Quote from: SeanB on August 31, 2014, 07:34:12 amAgreed. With the DMM Check Plus, I know my even my $5 DT830B (pair of them) are giving me good readings.I also use the 5V into the installed resistors and use that to do sanity check on other ranges. Since the resistors are of known value, connecting it to the fixed 5V gives me theoretical 1% sanity check on other ranges.

author: SeanB
author_rank: Super Contributor
timestamp: August 31, 2014, 08:24:06 am
content: I built my own using a cheap AD581KH and it has helped me be more convinced of the accuracy of my meters. Only bought the AD reference and used recycled parts for the rest of it.

author: HighVoltage
author_rank: Super Contributor
timestamp: August 31, 2014, 09:12:00 am
content: You could also look at Geller Labshttp://gellerlabs.com/SVR%20Series.htmAlthough the website explains that some parts are no longer available, you can send them an email and they will ship you a standard.I got one a few weeks back in a 10V version and it works great.I also have a DMMCheck Plus and I also can recommend it.

author: Wytnucls
author_rank: Super Contributor
timestamp: August 31, 2014, 10:17:58 am
content: I got this voltage reference from Franky and I can say it is fairly accurate, checked against my 6 1/2 Gossen meter and some others.http://www.ebay.com/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Module-/121200404799?pt=LH_DefaultDomain_0&hash=item1c381b693f

author: SeanB
author_rank: Super Contributor
timestamp: August 31, 2014, 10:49:41 am
content: Bought the same one from Frankie, and only had to add my own battery to it. I just leave it permanently on connected to a spare USB port, and modified it so the blue LED was running at a much lower current. 470R resistor changed to 18k, now the led is not a glowing room light when it turns on to charge the battery.

author: true
author_rank: Frequent Contributor
timestamp: August 31, 2014, 07:10:51 pm
content: Quote from: ModemHead on August 30, 2014, 12:00:24 pmHe was a dick to me. But the DMMCheck is a nice product.

author: Rick Law
author_rank: Super Contributor
timestamp: August 31, 2014, 09:14:55 pm
content: Quote from: Wytnucls on August 31, 2014, 10:17:58 amYeah, but the rest of us"mere mortals" don't have a 6.5 digit DMM to verify...If I found out I have terminal illness, I may spring for a 6.5 digit DMM. Come to think of it, how come many sellers/manufacturers have "first time buyer incentive" but none ever have "last time buyer incentive"? It would be great for advertising because they can honestly advertise: "John Doe (RIP) purchased our DMM, and it was proven it did lasted him a life time... click below on video... The one DMM that truely lasts for a life time..."

author: edavid
author_rank: Super Contributor
timestamp: September 01, 2014, 12:35:18 am
content: Quote from: Rick Law on August 31, 2014, 09:14:55 pmYou can certainly get an HP 3456A for under $100. My Fluke 8506A (7.5 digit) was only $80.

author: Wytnucls
author_rank: Super Contributor
timestamp: September 01, 2014, 03:49:02 am
content: All I was trying to say is that the manufacturer seems to spend the time required to calibrate the product properly. Of course, calibration doesn't last for ever, but should be good enough for an occasional sanity check. I do like the 'last time buyer' incentive idea though...

author: Rick Law
author_rank: Super Contributor
timestamp: September 01, 2014, 04:37:10 am
content: Quote from: Wytnucls on September 01, 2014, 03:49:02 amWytnucls,Yeah, I actually got what you were trying to say. I just wanted to pipe in so as to shall I say, "show admiration for your tool selection." I actually had been looking at that with interest. Rather amazed something so accurate can be packaged in something so compact as the 6.5 digit Gossen. But as merely hobbyist, I would not be able to justify that. I have no real need for so accurate a meter just to poke around as hobbyist. Even my UT61E is almost an overkill for me.(re: my joke about "last time buyers incentive")In the USA, we have something along that line. Most restaurants will have a "Senior Menu" where meals are cheaper.Rick

author: Rick Law
author_rank: Super Contributor
timestamp: September 01, 2014, 04:38:50 am
content: Quote from: Rick Law on September 01, 2014, 04:37:10 am

author: Wytnucls
author_rank: Super Contributor
timestamp: September 01, 2014, 10:43:39 am
content: No, I hadn't checked for spurious transients on the scope. The multimeter voltage readings are fairly stable on the last digit (+/-2). The ADC wouldn't pick up transients shorter than 100uS, I would think.Had a quick test on the scope:AC coupling shows an average of 300uVpp on a 100uS time base, with low pass filter set at 5kHz. Possibly into the noise floor of the scope.

author: Wytnucls
author_rank: Super Contributor
timestamp: September 01, 2014, 05:41:37 pm
content: Long term worst stability is 25ppm/1000hrs, according to the datasheet.Short transients, if they exist, won't get picked up by the DMM ADCs anyway.I found the reference adequate for my 40,000 count and 240,000 count meters. Don't forget that ambient temperature should be 23 degrees C for accuracy.

author: Terabyte2007
author_rank: Frequent Contributor
timestamp: September 02, 2014, 02:08:29 pm
content: Quote from: Wytnucls on August 31, 2014, 10:17:58 amI have 2 of these and they are a bit noisy at the higher reference voltages such as 7.5V and 10V. Both of them do this. At 10V, the noise is significantly higher than 10mV. 2.5V and 5V are very good.