Team-BHP (https://www.team-bhp.com/forum/)

-   DIY - Do it yourself (https://www.team-bhp.com/forum/diy-do-yourself/)

-   -   Tools for a DIYer (https://www.team-bhp.com/forum/diy-do-yourself/88566-tools-diyer-114.html)

The ones that rust are generally the el-cheapo Chinese manufactured bits. I have Bosch, Black & Decker drill and screw driver bits purchased over a decade back that have no sign of rust. Of course Pune has low humidity throughout the year except the rainy season and that helps a lot in keeping rust away from any metal object, even automobiles.

Silicone grease is an excellent option but more expensive than Vaseline or WD-40. So I use SG only for electrical and automobile parts that actually need it. Another way to preserve the tools is to store them in a zip-lok bag. Squeeze the air out before sealing the bag.

The best tools that I've used were Cocraft from Swedish retailer clas ohlson. These dont rust and go on like new. The Multibit Ratchet Screwdriver was the cheapest around and also the most long lasting. Shines like silver!

Any recommendations on a simple reliable Digital multimeter? Preferably one with standard batteries. And easy on the pocket.

I'd recommend a Fluke 101 or a competing budget model for e.g. an Extech MN36.

Please don't buy those cheap unbranded Chinese meters especially if you intend checking the mains or other high voltages.

What basic model should I get to cover household AC current measurements? And capacitors?

The Fluke 101 should do the job depending on how large the capacitors are. It's small (fits in your palm I think) and light. I intend buying a F101 as a part of my car toolkit.

If you're serious about measurements get a Fluke 115. This is a great True RMS DMM for the money. It's pretty compact and really well made. It's my go to meter even though I have other high range Fluke DMM models. But those are large and a pain to lug around and I nearly always pick up my trusty F115.

Note - You require True RMS meters to accurately measure non sine wave for e.g. stepped sine wave or square wave outputs from some inverters and UPSes. Read more here:

What is True RMS

Thanks for the quick reply. I've decided to stick with fluke.
The wiring in my native place is single phase and circuit breakers and wiring sizes are haphazard.

I want to be able to measure AC current drawn under loads by various wires at terminal sockets, behind circuit breakers and distribution wires to make sure the loads are evenly distributed.

For that purpose I've decided to go with a clampmeter that can measure AC current drawn safely without physical contact. The Fluke 362 and 302+ seem to be the thing to get the job done.

Not true RMS I think, but close enough for government work. :)

https://www.amazon.in/Fluke-FLUKE-36.../dp/B00K17N6AI

https://www.amazon.in/dp/B00V6BC6CW

Fluke instruments are the one of the best. As a student back in the '80s who repaired consumer electronics as a hobby it was a dream to own a Fluke some day. :) So I used an analogue Sanwa meter gifted to me by my maternal grandfather.

Your choices are like nice models at a great price point. However, clamp meters are a bit limited in functionality & measurement range compared to DMMs. For e.g. you cannot measure capacitance which I believe you wish to do. Please check the instrument's measuring range & CAT rating carefully. You can use these to take measurements up to the junction/distribution boxes in your building/installation (CAT III). Read more here: Measurement categories Safety is paramount when measuring AC mains.

Also, do remember that bit about TRMS whilst measuring outputs from some inverters/UPSes.

Cheers!

R2D2, for a few years now I have owned a Uni-T clamp/DMM. It was not very cheap, but, bought as an on-sale item at a UK Maplin's shop, it was a lower-price for such a meter.

95.9% of its use is as a humble battery checker, 4% as a humble continuity checker, and 1% as a clamp mains-current checker.

I have some dissatisfaction with it. I am not sure if it always did this, but, as a humble battery checker, it is telling me that air is generating random numbers of DC voltage! Whilst it is not bad at telling me the voltage of a moderate/good AA battery, it will not fix on a number for an effectively-dead one, again, giving me random numbers. The only time it reads 0 volts DC is if I touch the probes together.

Much as I like collecting gadgets, I am not an electronics guy and I do not have the need for a sophisticated DMM. But I would like one that is good at the few things for which I use it... and I would like one that will show me the start-up current drawn by equipment like AC, pumps, etc.

What would you recommend. Is that peak measurement only available on the more-expensive clamp meters?

That's pretty normal in some high impendance DMMs. My Fluke DMMs do that too. So I wouldn't worry. The last (least significant) digits seems to count an input voltage (in mV) when there is no input connected in AC/DC mode.

But it should settle down to zero or near zero. As long as it shows '0' when the leads are connected it should be fine.

For all practical purposes that level of error (if I may call it that) in resolution should not be of concern in domestic/home use measurements. I am assuming nobody messed with the factory calibration.

What you need is a feature called 'in-rush current' measurements available on mid and higher end clamp meters. These CMs are generally used by electricians and refrigeration technicians maintaining inductive loads like motors and compressors. Here's one such model: Mastech Clamp Meter

Fluke products are generally expensive so consider CMs from brands like Extech, Mastech, MetRavi & Rishabh. The last two are Indian makes.

"In-rush:" That's the technical term I had forgotten! Thanks, and thanks for the recommendations. I was thinking I might have to spend tens of thousands for the facility, which I cannot justify.

<a few minutes later>

One Amazon-dot-com reviewer is talking about that Mastech being a good deal at USD70. Can't be bad for 6K Rs, then! :D


.

I have that mastech model ms2108, it's good for measuring DC amps but it takes a while to Zero the reading for measuring AC current and but yes it does have the inrush current capabilty.
Uni-T mid to high end versions of their multimeters are becoming real value for money(compared to fluke), very very close to some reference level $700+ bench multimeters.

I bought the mastech in SP road for 3k in 2012 but then again dollar was Rs 5x.xx, now its more then 60.xx plus earlier it was 5% vat, now its mostly 12 or 18% gst.

I to started out with a analog sanwa in the 90s then upgraded to Indian brand Meco in late 90s, now have a mastech for measuring current.
Regarding mastech do not drop it, the calibration will be off, there are pots on the inside to adjust but you will need a fluke or some other high end multimeter to calibrate it.

Since we've been discussing DMMs and CMs. Safety comes first when you're measuring high voltages (V, over 30V) and current (A).

Please take safety seriously. I don't need to tell you electricity can kill if it passes through your body with sufficient pressure (voltage) and current/flow (amps). You may not get a second chance.

DMM Safety Tips

PS - I've lived to tell of my experience of getting zapped by the FBT (fly back or high tension transformer) of old cathode ray tube TVs which generally have voltages in KVs (15-24KV) but very low amperage. And this is when I was wearing insulating footwear. But the experience was, well, more than just shocking. It hurts and is very, very unpleasant. My 1st experience of an electric shock was when I was a small kid and playfully inserted my fingers into a 15A wall socket. :) They didn't have safety shutters back in those days. I still remember that experience all these decades later! So, take care.

I have had plenty of short-sharp-buzz 240 volt shocks, touching the wrong thing. I am lucky: nonthing bad happened. But the worst thing was...

I was fixing wire mesh over the cable entry points to our meter cupboard, because rats were getting in. This is the most stupid and dangerous mistake I made: I was working close to 3-phase mains, but because I was not doing electrical work, I did not even think about it. After all, everything dangerous was boxed, right?

Suddenly I felt like I had a big punch to the head. This is the only time I have ever screamed out loud!

What had happened: there was a fault in meter, with current leaking to the metal case, and I had just brushed my head againt it. I got out the meter: >400 volts. I felt fine, although very shaken, but we phoned a doc who advised coming for an ECG. Everything was OK. But it could so easily have been a no-second-chances accident.

Be safe working near as well as with, electricity.

(my first analogue multimeter, I blew up, poking around inside a TV, with no clue what I was doing <blush>)

:eek: How did you get 400V as domestic supply. Assuming this was the home meter enclosure? 440V is mostly for industries and supply to housing colonies with 3 Ph step down transformers like the one I live in.

I never go near that transformer. I've seen cats, squirrels and birds get instantly electrocuted with a loud bang and a puff of smoke. The dead animal looks burnt to a crisp. The SEB linesmen switch off power before entering the enclosure. We are all bags of saline solution after all. :D

100% true, one must be careful when working with or near energised terminals or wires. That's why those HT cabinets and transformers are fenced off to discourage people and animals from getting too close.