Klein Tools MM200 Multimeter - Page 1
Forum section: electronics / general

author: FenderBender
author_rank: Super Contributor
timestamp: January 30, 2012, 03:44:20 am
content: So I bought this meter for $49 at Home Depot. I really didn't know what I was going to get, but my curiosity was getting the best of me and needed another meter pronto.So pros and cons...Pros-1.) Good feel to it2.) Auto-ranging3.) Decent looking (Agilent copiers *cough*)4.) Lots of functionality (temperature, capacitance etc.)5.) Reasonable internal build quality6.) Excellent range switch7.) Backlight8.) Good test leads and included K-type thermocoupleCons-1.) It seems it was not properly calibrated from the factory (Edit: I have posted below showing you which potentiometers adjust what range.)2.) Crap battery3.) A little overpriced? (Still making up my mind)EDIT: Sorry some of the photos are tilted. I might get to that later.

author: retiredcaps
author_rank: Super Contributor
timestamp: January 30, 2012, 05:16:29 am
content: Quote from: FenderBender on January 30, 2012, 03:44:20 amThanks for sharing. I'm always interested in seeing what the insides look like.My method is far from scientific and I don't have any fancy power equipment and/or calibration, but I recently gathered up my 3 multimeters and hooked them up to an ATX power supply and had each measure the 12V and 5V DC via the molex connector simultaneously.Maybe try the same for the above and then you can see the differences more clearly. If the Klein is that far off, I think I see possible adjustments on your board?If this were my multimeter and I couldn't adjust it, I would return it for money back.

author: ron
author_rank: Regular Contributor
timestamp: January 30, 2012, 06:12:42 am
content: Having mA & uA on the same terminal as V and ohm is asking for trouble imho.

author: JuKu
author_rank: Frequent Contributor
timestamp: January 30, 2012, 07:29:08 am
content: A meter that doesn't give accurate numbers doesn't fulfill its purpose of existence.

author: cybergibbons
author_rank: Frequent Contributor
timestamp: January 30, 2012, 08:26:01 am
content: Quote from: ron on January 30, 2012, 06:12:42 amYep, keep a load of the little fuses spare for when you turn the dial to the wrong position.

author: FenderBender
author_rank: Super Contributor
timestamp: January 30, 2012, 08:45:51 pm
content: Quote from: JuKu on January 30, 2012, 07:29:08 amYeah I know. I contacted Klein looking for calibration data because I'm POed. Manual states 0.5% for voltage DC. I think it's atleast 1-1.5% off in a few of the cases I tested.

author: FenderBender
author_rank: Super Contributor
timestamp: February 16, 2012, 11:55:26 pm
content: So of course Klein said they'd pass my request onto the Meter team, but the so called meter team does not seem to want to talk to me...so I did my own investigation.So I figured out the function of two of the many potentiometers on this meter's board. I have a picture attached.--> The one in the purple box is for adjusting the voltage measurement. I believe only for DC voltage.--> The one in the yellow box is for adjusting capacitance measurement.Both of these were out of spec on my meter. I did not use a precision reference, however I did have 3 meters reading very close to each other and the Klein way far off. For capacitance, my meter was roughly 6% off my "accepted value". The spec was supposed to be +/- 3%. For voltage, I was getting around 1.3% out on a 9V battery (measuring 8.90V on other 3 meters), as a reference. Spec was +/- 0.5%Again, please don't criticize my ghetto calibration here.However, if anyone else needs to calibrate their own, I know for a fact what those two pots do. Also, if you just look at the board, you can probably tell what the others might do.

author: IanB
author_rank: Super Contributor
timestamp: February 17, 2012, 03:02:13 am
content: These meters with adjustable pots are very convenient. Usually they seem to be scale adjustments and may need the lightest of touches. You adjust to get a good reading at some known reference point, then check against a few other points on the scale. If all seems good you are done. Otherwise the scale might have some non-linearity and you may need to adjust one point a little high to balance out another point reading a little low.

author: FenderBender
author_rank: Super Contributor
timestamp: February 17, 2012, 03:08:58 am
content: Quote from: IanB on February 17, 2012, 03:02:13 amYeah I didn't really do too many points. I did think about that: Non-linearity.I might check a few more voltages/capacitances and see if anything shows up undesirable.And these pots are very touchy. They're single turn SMD pots. Pretty much suck, but hey a machine does it I think anyway.

author: Unknown
author_rank: Unknown
timestamp: February 18, 2012, 07:18:23 pm
content: Quote from: FenderBender on February 17, 2012, 03:08:58 amI'm not so sure. Machines are the reason why pretty much all manufacturers use closed case calibration these days. The only manufacturers still using them are the low-end manufacturers from countries with cheap labor. Guess how likely they are to invest in sophisticated equipment versus some unskilled laborer adjusting the trimmers to a dubious voltage reference (eg. a battery which may become empty at some point) 16 hours per day.

author: FenderBender
author_rank: Super Contributor
timestamp: February 18, 2012, 08:45:05 pm
content: Well I always heard that those type of trimmers were intended for a machine to adjust. Though perhaps you are saying through software?Who knows.

author: thedougler604
author_rank: Newbie
timestamp: June 08, 2013, 09:34:49 pm
content: I bought one of these today, and it's set to work in fahrenheit. I can see that the LCD has a degrees C light on it, but I can't figure out how to get it there? I've emailed and called Klein, but they're closed today.Does anyone know how to set the temperature unit on their mm200?

author: saturation
author_rank: Super Contributor
timestamp: June 09, 2013, 01:13:06 pm
content: It seems decently made; its also ETL listed for safety, and the casing is double walled in addition to the rubberized sleeve. So the only issue is accuracy, precision and features.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: June 09, 2013, 01:23:05 pm
content: It's almost identical to the Mastech MS8233E I looked at a while ago:https://www.eevblog.com/forum/testgear/mastech-ms-8233e-ms-8240d-and-ms-8250c/msg160990/#msg160990Only differences are that the MS8233E has the NCV detection and a MAX functions, while lacking the frequency measurement that the MM200 has.

author: albert001
author_rank: Regular Contributor
timestamp: May 20, 2018, 09:27:11 am
content: May be late to reply to old post however, the MM200 I have works great accept that it often takes a second and sometimes a third try for it to turn on.Sometimes it turns on the first try but often it only comes on after a second time and less often a third.I haven't tried taking it apart to determine the cause. I picked it more than year ago from an eBay seller who was selling the MM200 as new for around ~$15.00 with shipping. Works ok but sometime has a problem turning on the first time, set it to off then on again it usually turns on.

author: Shock
author_rank: Super Contributor
timestamp: May 20, 2018, 12:44:40 pm
content: Quote from: albert001 on May 20, 2018, 09:27:11 amHoly Necro bump. We have a repair forum here by the way.Try replacing the battery with new, if that doesn't work check the battery contact, cable where it meets the PCB and excessive wear on the PCB switch tracks, plus any corrosion or dirty button contacts in general. It's normally either that or a bad crapacitor.