How thermistor protects your power supply - NTC protection against Inrush current

Show thermistor or an NTC is used to control inrush or surge current
#NTC, #Thermistor, #inrushcurrent
Link to NTC/Thermistor: amzn.to/46C6lYM
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[@blitzroehre1807]

... at first I thought you were doing an evaluation of various multimeters currently on the market. Thanks for explaining so well :-)

[@KissAnalog]

LOL, thanks so much! Always feel free to ask any questions!!!

[@noneofabove5586]

Thanks ! I just discovered this type of inrush current limiter. I had a meter setup similar to yours. I also recorded about 254 degrees F on the ntc. Mine is to limit the inrush current on my isolation transformer. I needed to keep it from poping the house circuit breaker. Before the ntc I had an instantanous draw of 30,000 watts this would pop the breaker instantly. After it was about 6000 watts. Thanks again.

[@analoghardwaretops3976]

Hi there!! just few days ago came across this..your " Y.T. channel..& I must say you really do HAVE a "Captivating" & Infectious Introductory SMILE.. 👍👍👍🙂🙂 ..N.T.C.'s.... They're great for this " initial " ..Power Up sequence...but then it's usefulness is over once heated up ... , it remains so as long as current flows through it.. ( low res. region) A momentary power outage, or one that's less than ( approx. twice it's thermal time constant) , the NTC will not cool down ( reset)sufficiently.. so it's always better to have a time delayed .... ( 3-5thermal t.c.long ) relay that latches in later..and bypasses the NTC.

[@KissAnalog]

Thanks so much! You make some excellent points! NTCs are low cost and easy, but do come with their shortcomings;)

[@analoghardwaretops3976]

@@KissAnalog THANKS FOR THE REPLY..

[@engjds]

@@KissAnalog I am bewildered, I am wanting to protect my 240VAC input to 330V DC power supply, capacitance is 2x470uF, its 1A max, now I don't know whether to use to NTC's, MOVs or TVS diodes, I want to protect the HV amplifier section, do I use MOV's on the AC input to prevent voltage surges, then NTC's on the power feed into the HV amp for current surges? MOV's I read degrade with time, but no clear information how long they last, which made me wonder if I should instead opt for TVs diodes? Reaction time for my project is important, getting to that low resistance within say 3 seconds.

[@dragan3290]

Great video. I have learnt more from KZbin vids like yours than my electronics course online by Penn foster. Saved,subbed and thanks! Cheers from Australia 🙂👍

[@KissAnalog]

That's awesome! I'm happy to have you on board;)

[@Yorumcu63]

Finally I was understand thermistor with this great video.Thank you for this video

[@KissAnalog]

Thant's so great! Thanks for this awesome feedback!

[@jaykesapalaran5434]

Very much informative and easy to understand 💌 THANK YOU VERY MUCH for sharing your knowledge ❤️

[@KissAnalog]

Thanks so much! I appreciate you!

[@ubertcoolie8694]

Thanks for your great video. In the Nintendo Switch ac adapter, one ac power plug goes into a thermoster and the other into a Square Slow Blow Micro Fuse. Perhaps you can talk about the differences and why it doesn't matter which way the plug is plugged into the electric outlet.

[@KissAnalog]

Thank you for this feedback! That is a great topic - thank you!!

[@davidnguyen5028]

I bought a bunch of NTC CL101, I just noticed that the initial resistance isn’t very high. They’re rated for 16amp. I’d figure that the resistance would be higher, but there not. So now I wonder if they’re really going to help at all.

[@KissAnalog]

Great question! They are rated at 0.5 ohm when they are at room temp (I believe), so they will slow down the inrush but it could still be quite high. You could place 2 in series if you think that will help you more. Thoughts?

[@rathnasiri5460]

Thank you,learned a lot and have a question.I have a laptop power supply in which a ntc-50 is blown and for the replacement I have a ntc- 10d from a another PC power supply will it work?thank you.

[@KissAnalog]

It probably will. One thing that is important is the current handling capability. You want one that can handle at least the same amount of current. If it is physically larger in diameter and/or fatter, then it probably is OK.

[@rathnasiri5460]

@@KissAnalog Thank you very much sir helped a lot

[@Dinco422]

So as I'm understanding thermistors can only be used in DC circuits correct ? No AC. And it's connected in parallel. Do you need to add a resistor on the + side or something like that ? Or straight up in parallel and that's it.

[@joeprogrock]

Great video I have a question please. I'm repairing a guitar bass amp and it has a NTC (ntc100k) that appears to have been glued to the heatsink on one of the power transistors in the output stage. It appears to have dislodged from the heatsink, should I glue it to the heatsink and if so what is used. Thanks

[@KissAnalog]

Great question. An NTC drops in resistance with heat, so it would probably only be safer off the heat sink, but if they glued it to the heat sink that might be better in this case. I think if it is physically touching the heat sink that should be enough. Not knowing what this NTC is being used for. Probably inrush current to power supply.

[@joeprogrock]

@@KissAnalog thanks for your prompt reply I'm doing a repair so it appears that it was glued to the heatsink, do you know what glue I can use please

[@KissAnalog]

Yes, I like this, but there are other options of course: amzn.to/3NoHAqA

[@anthonymajors7844]

Good job. I appreciate you arranging this demo. I have a question regarding thermoelectric or Peltier modules (TEMs) and inrush current. TEM performance drops with excessive on/off cycling or excessive current level cycling. Do you think inrush current limiting would extend TEM life under excessive cycling conditions? Thanks for any comments.

[@KissAnalog]

Hi Anthony. Thank you for your support! I have not heard that inrush was a problem. I have heard that the ripple voltage at the power supply is good to be lower than 10% and preferably 5% or better. It is funny, because I've purchased a couple of TECs to start experimenting. I'll have to do a video to show what I find. Let me know what you find or if you have any other comments/questions.

[@anthonymajors7844]

@@KissAnalog Have to confess I'm not that far into the testing phase. However, got this note when discussing with Allied Thermal: "Generally thermal cycling causes a change (increase) in electrical resistance and will reduce the cooling performance of the module over time. These changes are generally a slow progression like fatigue in metals. The severity depends on the severity of the cycles. The usual way to the monitor the change is to measure the electrical resistance at a fixed temperature, say at 25C. Resistance is measured using an AC resistance meter (LCR meter)." Also found this on ferrotec.com: "...four factors relate to failure rate in thermal cycling (of Peltier modules) including (1) the total number of cycles,..." I'm guessing the underlying, destructive dynamic is inrush current, but I may be wrong. If you do a video, I'd certainly be interested. - Anthony

[@KissAnalog]

Thanks Anthony - great info. I’ll do a bit more research and do that video;)

[@theguitaramptech]

H Eddy, is there a reason why Tube amps don't use NTC Thermistors?. A tube rectifier is a limiting component as it can only handle a limited reservoir capacitance. Could it have something to do with the 2 power-on stage of (1) transformer energizing, and (2) the Standby to ON which charges the main filter caps?

[@KissAnalog]

Great question! I think it might be because the tube amps don't typically have the huge bulk capacitors. This is probably due to the voltage levels that the tubes run on, and it could be that many tube amps were/are Class A power amplifiers that don't have the same dynamic load to the bulk capacitor. Then there's the age and engineering practices that are hard to change - even when there's a better way;)

[@theguitaramptech]

@@KissAnalog thanks Eddy. I’m going to install a NTC in a tube amp and hit the power switch with a 12’ long pole. If you don’t see me on the front page of the Sydney morning Herald, you’ll know everything worked out just fine.

[@surgingcircuits6955]

Thx for the video. Are there any considerations using NTCs (or PTCs) in series vs parallel to a load?

[@KissAnalog]

Thanks for the question. Yes PTCs and/or NTCs are typically used in series to the load to protect it. The PTCs act as resettable fuses and thte NTCs or thermistors act to protect against inrush current.

[@surgingcircuits6955]

@@KissAnalog, Excellent! Thx

[@surgingcircuits6955]

@@KissAnalog, one more... then an NTC in parallel to protect an AC circuit from inrush before rectification?

[@KissAnalog]

Yes, you can place the NTC in front of every thing to protect the rectifiers.

[@surgingcircuits6955]

@@KissAnalog Thanks so much.

[@BladeforgerKLX]

Very cool!!! I think I'm on the right track, maybe. How would you use one of these to keep a refrigerator from stalling out an inverter when using 12V power as a backup for power outages? Can it simply go inline on the 120V side (both wires?)??

[@KissAnalog]

BladeforgerKLX I’d have to understand the connection better, but if it is in series, then one should do it. Thanks for the comment! I’d love to hear how it turns out!

[@BladeforgerKLX]

@@KissAnalog Thanks!!!

[@KissAnalog]

+BladeforgerKLX You bet!

[@Bianchi77]

Nice info, if there was a short, what is the sign of ptc failure?

[@KissAnalog]

Thank you! Often the PTC will break open (lead break away) or shatter, but they are robust and because they operate like a fuse - they protect themselves;)

[@reedreamer9518]

I didn't see any current limiting at all - the Fluke 189 and the Hantek current probe read 2.5 amps from the moment the circuit was switched on and held steady while the NTC headed up. Maybe the current was limited for a few milliseconds maybe?

[@gregreynolds5686]

Often, a few ms is all you need. The reducing volt drop clearly shows the NTC behaviour and general principle though.

[@izzzzzz6]

Do you cover thermistor bypass circuits? I believe if they are used for slower charge of caps, once charged it is stitched out of circuit.

[@MrEd-cs7us]

You're very good at explaining the Thermistor but I could only quess what size of thermistor to get! I have a toroidal transformer 110v Primary 40v 10 amp Secondary. Building power supply for audio amplifier. I would assume it to be a large one. Appreciate your time in replying!

[@KissAnalog]

Thanks for the great question! I have a couple more vids on thermistors, here's one: kzbin.info/www/bejne/n3vQqJxtlNl1gq8 You would want to select a thermistor that has a current rating higher than the circuit or fuse is rated so it is no the weak link. You can place the thermistor on the primary side where the current is lower if that works better for your circuit. Let me know if you have any more questions and if I need to better answer this one;)

[@fluxcapacitor3273]

hello, great video, learnt a lot. my question is, do 2 200V 680uf capacitor requires NTC to avoid in rush current?

[@KissAnalog]

Great question! I don't think that is a lot of capacitance, so I think it is OK without the NTC. But then, if you have a small current rated fuse - then maybe it would benefit from the NTC. I'd think it would be OK, but I'd really have to know more to give a definitive answer.

[@fluxcapacitor3273]

@@KissAnalog thanks for the reply, there's little fuse in the smps , i changed stock reservoirs capacitors (2x200v200uf crappy brand) with nichicon 2x200v680uf and thought this could stress the entire circuit.however i don't know what ampere ntc i can add.5A is enough ? Sorry for further question:)

[@fluxcapacitor3273]

@@KissAnalog May i ask what value of ntc i can use for a 100watt amplifier? Resistance values are so different like 10ohm to 50kohm huge difference, I'm stuck at value selection, please help :)

[@microfix6035]

very cool....break down

[@KissAnalog]

Micro Fix thank you!

[@BenBilesBB-box]

Hi nice explanation and demo of how these things work. I bought one for a bipolar power supply I designed for an audio amp and was hoping it might protect the amp from an accidental short ( in case ). I tried the NTC on a dummy load I have and was surprised at how many wats the thing could deliver before it limited current. I think a 2nd video on how to select the value for what limiting you need would be really great. I bought a NTC 10D-11 and I think I should have ordered a smaller one but don't understand the values.

[@BenBilesBB-box]

wait , I should be using a fuse to protect against shorts and the NTC to protect against inrush..

[@KissAnalog]

Thanks - I think I should do a follow up video;)

[@KissAnalog]

Yes, a fuse or a resettable fuse (PTC) for shorts and NTC for inrush;)

[@BenBilesBB-box]

@@KissAnalog ah , it was a PTC I was looking for all the time !

[@clems6989]

Wish you would have shown the scope capture for longer...

[@KissAnalog]

Thanks for the feedback! What did you want me to show? Maybe I can do it in a new video.

[@moniftormos6881]

Great teacher

[@KissAnalog]

Thank you! 😃 I appreciate you!

[@greatfulcoast]

Please help me with this question. If the termistor in a power supply explodes what other components may be damage? Thank you.

[@KissAnalog]

It depends on where it is in the circuit. If it is in the input (EMI) circuit, then it could be a diode rectifier. Or it could be a transistor. Check for shorts.

[@TheSusananderson1]

Nice explanation

[@KissAnalog]

Thank you. I appreciate you!

[@claude77573]

Did you get a chance to look up the name of that putty?

[@alicekichlu215]

GOOD DEMONSTRATION.

[@KissAnalog]

Alice Kichlu thank you!

[@mixme8655]

Thank you sir

[@KissAnalog]

Thank you!

[@josepeixoto3384]

so,when it heats up, its resistance goes down to zero, more current can flow ,how and what does it protect?

[@KissAnalog]

Thanks - and yes - it protects against the initial rush of current to charge the caps and then it heats up to take itself out of the path. The inrush current is a fraction of a second.

[@fp274]

can i use 3 NTC thermistors in parallel - i have 3 15ohm/8A ntc would like to use them in my dc welder - i think i will get 5ohm/24A - my welder input is max 15A at 230v

[@KissAnalog]

That's a great idea - and yes you can put them in parallel. It might be a good idea to put heatshrink around the 3 of them so that they are near the same temperature - so that their resistances track as well. I like the 24 A capability for 15 A max, so that's a nice safety margin. I'd love to hear how it works.

[@fp274]

@@KissAnalog. nice idea with the heat shrink, found 3 ntc with the same resistance with my multi-meter, yes it works, but time will tell

[@johnnoodles6088]

@@fp274 ntc's should not be used in parallel since one of the unit's will tend to conduct nearly all the current available and blow one by one

[@akeonly1]

Hello Sir, I recently have a power outage which kill my Haier AC outdoor power supply unit, what I notice is during the power outage there is a cycle of on/off from the AC main. After several hour of research I found that the power supply IC (1200P100) is dead so I replaced it and it worked....but there was another power outage today which kills it again, so I suspect that there's could be something wrong with the surge protection circuit on the board. Do you think I'm in the right direction? Or there's other components that I should look at? 🙏🙏🙏Thanks

[@KissAnalog]

So the mains that power this AC unit dropped out and then came back - but then it seemed to kill the AC unit? It would seem that there must be transients getting through that is causing this damage. So yes, I think you are on the right track. Pin 8 of that chip has a resistor to the high voltage but if this voltage has a spike it could kill the chip. Is there an MOV on the board?

[@akeonly1]

Yes, the main 220VAC dropped and come back. So if I put an NTC to prevent that high voltage spike it should help right? What I don't understand is that where is that high voltage spike could come from, Is simply by turning on and off the main AC power cause that spike? and i assume MOV is metal oxide varistor I found one on 5 pin which is IRFUC20. Thanks for getting back to me, really appreciate it :D

[@444guns]

Thanks for the video. So, let me see if i understood correctly: an NTC thermistor limits the current at first because at room temperature it has a (relatively) high resistance. Then, as current passes through it, it becomes warmer and warmer, lowering it's resistance, allowing for more current until it reaches a peak of whatever current you need in your circuit. But from that point on, it stays warm (or should i say hot) for the rest of your device functioning. Correct ? Wouldn't a PTC thermistor be a better idea, working cool and only heating up when inrush current happens, by driving it's resistance higher, therefore allowing less current through the circuit ? Or maybe it's speed of getting it's resistance higher would be just too slow for this job ?

[@KissAnalog]

You have the operation correct. The NTC is preferred to keep losses down in operation. The PTC is selected to keep resistance low in normal operation and only go high during very high current like a short circuit.

[@444guns]

@@KissAnalog Wow, that was fast :))) Thanks

[@keithcoltron3171]

Please tell me you're joking, yes? He explained it 201 times!!!!! OMG If you can't grasp something this basic you're going to have B I G problems with electronics, sorry, what do you need at the start to limit, block, stop, prevent, close the door to high rushing in current? Gordon Bennet give me a break! you nearly had me there I thought you were serious, not funny! I nearly pulled the trigger :-) very good though!

[@444guns]

@@keithcoltron3171 i have no clue whatsoever what you're talking about ... yes, i'm a beginner, yes i still have alot to learn. But i'm no idiot by any means, and i've managed to learn alot in my life all by myself. So no, i won't have BIG problems. It's you who has problems that other people sometimes don't understand something that YOU consider to be soo simple, and at the same time feel the need to comment. I mean, sometimes i see something similar as well, but i don't feel the need to go "man, you're so dumb" ... And who is "Gordon Bennet" anyway ??

[@keithcoltron3171]

@@KissAnalog But NO he hasn't understood otherwise he wouldn't suggest that! NO WAY has he grasped the idea, sorry that's dyslexic? ass about face???????? he knows the starting resistance of each but can't grasp the theory? I think he is pulling your leg though?

[@mixme8655]

Sir what device should I use to stop the motor of fan when the blade is not spinning?

[@KissAnalog]

Great question! Are a you asking about a resettable fuse or inrush protection.

[@mixme8655]

@@KissAnalog Sir the resetable fuse I think, so that I can reset it after fixing the not spinning blade . Thank you ( the fan is an AC operated the size is that of PC use next to small one)

[@hestheMaster]

Good demo. The thermistor really gets hot!🔥

[@KissAnalog]

he's the Master Thank you! I appreciate you!

[@Aizen732]

I found this video when I was searching why my cheap aliexpress 8A led power supply popped when I was turning it on. I found exploded component NTC 10D-9. That damn power supply was working few days but made uneven hissing noise and burnt varnish smell. I wonder if it is thermistor fault or other components.

[@KissAnalog]

That's a great question. I'd think that the circuit was pulling more current than it was designed to pull. Maybe a bad LED pulling current? The NTC should drop in resistance value with heat/current - so if it actually got to hot and damaged itself - then it is probably a load problem.

[@Aizen732]

@@KissAnalog My socket power meter showed 60w and multimeter about 4a at 12v.

[@KissAnalog]

How is it going? Did you find the problem?

[@Aizen732]

@@KissAnalog I opened that power supply out of curiosity. I don't have any spare parts or equipment to repair it, so I will leave it. I ended using old atx PC power supply. It has plenty protection and power.

[@CoquiAudio]

hello, sir you don't mind if I use just a few minutes of your video for my channel? 😊

[@KissAnalog]

That would be awesome! Thank you!

[@CoquiAudio]

@@KissAnalog double awesome! 👍😊

[@carlcreary875]

Can the wrong thermistor cause my mosfets to stop work. Thanks

[@KissAnalog]

Possible maybe, but it would have to be really wrong;) What value is it at cold?

[@anandsingh8987]

Hello Sir, Your video might be awesome for intermediate fokes, but difficult for beginners to understand the whole concept and presentation you made. Please try to cover both beginner and experienced friendly by putting something theory, calculations, specifications, Inputs, outputs on plane ppt. As these will help to visualize more better when you are walking us though your videos.

[@KissAnalog]

Great feedback - thanks! I will cover this again and hopefully use the kiss methods;)

[@anandsingh8987]

@@KissAnalog Respected blessing..

[@jdlech]

I found it sometimes extremely difficult to find the right thermistor. Case in point, I had a recent project that could benefit from a thermistor, but none could be found to fit the bill. I needed to limit inrush current to 4 amps at 5 volts, with normal operating current being about 1 amp. (2.5A max on startup). Do you think I could find a thermistor to fit? Nope. My alternate solution was a 2v relay. It turns out, my power supply could handle the inrush current to charge 10500uF worth of capacitors, but not the capacitors AND powering the unit it was meant to power. So I used a relay and a resistor so the relay tripped as the voltage approached 5V. The relay coil is wired in parallel with the caps. The extra resistor fine tuned the trip voltage to just under 5v, and minimized the parasitic current through the coil. Thus, the caps are already mostly charged when the relay trips, feeding current to the unit. I essentially split the two inrush currents, handling one after the other. Finding a suitable relay and resistor was easy, and I didn't need any complicated soft start circuit. Another problem with thermistors is that they are really meant to go in series before the rectifier / power supply, which starves the power supply of both voltage and current. This is known as a 'brownout'. So it's meant for less complicated (unregulated?) power supplies that won't burn up under low voltage conditions. If you try to use one in series between the power supply and decoupling capacitors, you'll be creating a voltage divider network between the thermistor and whatever you're powering. That will reduce your available voltage output. Worse still, your voltage output will vary according to the thermistor temperature. This can get quite significant if you're using a low voltage power supply, or a low resistance load. In the case of my recent project, for instance, a 0.3Ω thermistor in series with a 3Ω load at 5V would result in the load only receiving 4.545V. And that's while dealing with a 250 degree component inside an enclosed plastic project box filled with capacitors. Not ideal. So why use one at all? They're great protectors of simple power supplies where regulation is not a priority - such as most audio and industrial equipment. They can also provide excellent short circuit protection, often better than fuses.

[@akierum]

They are in every brand name computer psu like corsair, antec, dell, etc why then?

[@windward2818]

Without a dedicated inrush limiting circuit or device, in their basic ideal form, both linear and switching AC to DC power supplies exhibit inrush current, and the magnitude seems to scale with power (also, switcher topology). Large linear supplies with transformers starting at about 300 VA will have significant inrush current just due to the transformer magnetization current stand alone without the bridge and smoothing capacitors connected. When you add the bridge and caps the inrush is even greater. Switching supplies also exhibit high inrush at moderate power ratings. So, obviously we need to address inrush current because of this unwanted high demand load at turn on. What is high? most designers of workable designs would say 7x to 10x the normal low line high load current. To work properly, NTC Thermistors must get hot, and this heat has to go somewhere, usually into the power supply enclosure which then will have to be cooled, usually by forced convection (a fan), which is fine for a power supply design which easily supports fan cooling, like a PC power supply. Because we now have to remove excess heat, you can see that the actual system cost for the NTC thermistor is greater than just the cost of the device itself. The NTC thermistor will generate heat continuously and this heat must be removed in someway. So, a design that uses an NTC thermistor requires the thermistor to become very hot and stay very hot. Why would I want a heat producing device that I must now vent just to handle a one time start up transient event? The answer it's cheap. A better approach is to limit current with a power resistor, and bypass after the inrush event. Selecting an effective value is relatively easy (actually easier than a NTC thermistor) for a linear supply, but more challenging with a switcher. However, as with any good design, we should monitor the temperature of the critical power devices (resistor, relay, etc.) usually placed in close proximity on the same heatsink for this purpose and interrupt mains power if overloaded (high temperature due to failure). There are other inrush approaches that "softstart" the circuit, but be aware that softstart circuits are not always that soft. For switcher design chip analysis first buy a reference design from the chip manufacturer and characterize on the bench before using it in a design. Make sure to include measuring radiated emission with a near field probe. If the board operates to your needs, then at the end, after all the other power supply performance checks, look at conducted emissions.

[@alexabadi7458]

You must get a multimeter for each birthday. :o)

[@KissAnalog]

Alex Abadi Is it that obvious;) Nice to hear from you!

[@randydicotti3975]

Ok I was thinking "damaging inrush current" but you're just talking about limiting initial inrush that wouldn't blow a fuse. I think

[@KissAnalog]

Great question - thanks! Yes, the initial inrush is typically the highest inrush current - charging the caps from zero to full voltage in an instant;) I think a thermistor will keep the fuse from blowing or stressing it, but it also protects the rectifier diodes that pass the current, and protects the capacitors from getting hit by the peak current.

[@edmart3778]

Hey sir, wich language are you speaking in that video?

[@KissAnalog]

I usually speak American English - but then who knows;)

[@T-DP]

Anyone interested in a thermistor production plant? Includes ovens, Dorst TPA press, vacuum metallization setup and know how.

[@KissAnalog]

That's a great question;) What country is it in just out of interest? :)

[@T-DP]

Belgium! Still producing now.

[@Drumhead2012]

how did Radio shack go out of business with you buying DVOM's?????

[@KissAnalog]

LMAO 😂

[@dmnx600rr]

Hello. Few weeks ago PSU killed my motherboard. I have switched pc on by pressing a button. I heard a pop and spotted a spark. Please see the video kzbin.info/www/bejne/pHKzaHiAZdlni8k. The thing that failed inside the psu is SCK 085 thermistor. Do you have any ide why this happened?

[@KissAnalog]

It could be undersized and it took just one more cycle to go. Or, there could be a short in the Power Supply that’s causing the fault.

[@bobert4522]

Hey buddy, I don’t think you have enough multimeters.

[@KissAnalog]

Thanks! I've been giving some away;)

[@bobert4522]

@@KissAnalog the FLIR DM285 has been my personal favorite

[@KissAnalog]

What a great meter! Let us know what you like about it please;)

[@bobert4522]

@@KissAnalog well the obvious is the built in thermal camera :). I actually bought the meter when I was working HVAC and I think that field of work could not serve this multimeter better. Being able to only carry one tool that can both measure electrically and visually for faults + potential sources of heat loss was amazing. Now that I’m into my EE work, I use it for diagnosing circuit faults. I prefer FLIR over Fluke because the specs are the same or better and I have had nothing but an amazing support experience. I originally had the DM284 and they released the DM285 which has Bluetooth capability for image sharing and remote measurements not long after my purchase. A little frustrated I emailed support about the possibility of an upgrade, sure enough, they exchanged it for the new model absolutely for free. Since FLIR/Teledyne owns Extech I have no worries about their capabilities to design a quality multimeter. I actually disassembled my meter as well and was impressed by the build quality. There is 0 cost cutting measures from what I can tell, and the lithium battery pack you can buy for the meter literally lasts a year. Granted I don’t use it everyday now that I do all my work at the bench with my HP 34011A, but it simply does not lose charge. Nothing but positive experiences, only gripe is you can’t record video with the thermal camera directly, but not a huge one.

[@akrsriv]

Wayyyy toooo muchhhh talkingggggg..... 4min video stretched to 15 with unimportant blabber.....

[@KissAnalog]

Yes I agree - sorry about that. I hope I’m getting better - still kind of new at this.

[@akrsriv]

@@KissAnalog it takes real guts to accept a criticism.. thumbs up for that.. 👍👍👍

[@KissAnalog]

Thanks - appreciate the feedback.

[@lucaburkhardt2592]

Dude, you could have said everything in this video in like 1 minute.

[@KissAnalog]

Go ahead and try - tell someone that doesn't have the background and see how successful you are. If I had done it in 1 minute - you would probably be here saying I rushed it. Some people just can't find it in themselves to find anything positive to say.