Thank you for the review. I think it would have been nice for the tester to include a battery holder for the most common batteries seen today... perhaps with a few flexible holders for sizes that don't match. Not sure I can really appreciate this tester tho, without a "reference" standard to ensure that it is accurate.
Profit margins have to be very thin on these instruments. You’d think it would not be worth the extra cost in labor and equipment to obliterate the part markings. I wonder if it really slows down other shady Chinese manufacturers from cloning their intellectual property? It is going to make repair of this instrument more difficult, but on the other hand it is probably intended to be disposable rather than repairable anyway.
The parts will be delabelled before soldering, easy enough with a reel to run them through a laser to scan and erase the marking, and then stick a new top cover on, and reel them up again. Must be places that do this for money, you take them the reel, and get the erased one back.
@KerryWong thanks for the review looks like an interesting item i just got a YR1035+ for £20. ,, this IR502 is coming up as only £32 seems like amazing value,, could you please maybe review the Hanmatek DOS1104 ,, its £150 for a 4 channel Oscilloscope,, i appreciate and value your opinions
The people at Tooltop sure are militant about scrubbing off identification. Looks like they obliterated every semiconductor number and even sanded the frequency off of the crystal.
Only reason is so no other chinaman copies the firmware and pcb design, reproduces the same product, but cheaper and destroys the original guys business that came up with it. Many such cases, sad. Still won't buy
@@TheDefpom Supposedly China is cracking down on trademark and intellectual property infringements. Sometimes I wonder how well that is enforced. In the past I have seen totally copied trademarks and the only way to tell is if the part does not perform to specification or if perhaps copy looks blurry or there is a misspelling somewhere else on the part.
@@simontay4851 Margin, they need low leakage, so used good capacitors, as this is likely how the AC test is coupled through. Wonder how well protected it is against reverse voltage, and them giving the pinout means it is easy to make bespoke test lead sets as well.
Yes, every power up like clamp ampere meters in DC you should power on and wait a little, short/close the contacts together and then zero it to compensate any drift or error from leads
I did not understand, if the meter uses the Kelvin method for measuring resistors. You would think so, but I would have like to have seen that proven, one way or the other. Cheers.
Perhaps the reason the meter is giving you unexpected “resistance” readings for the 100 ohm resistor is that it is actually measuring impedance. Is that resistor wire wound inside?
I just tested some wire wound resistors between 50 and 680 ohms. The maximum error I got at 1 kHz was 0.5%. Equipment ET431 and error based on Zs/DCR. The impedance was always > resistance, as you might expect. Between using REL and switching to a Vishay rectangular precision resistor, I bet the measurement will have less than 1% error.
This is surely useful for the off grid freak to weed out lazy batteries. Say your house has a 48V system and 12V lights, you can arrange the batteries to feed the lights from strong batteries rather than waste inequality inside the BMS and use a converter to reduce 48V down to 12V. Mustool is offering cheap solutions for many DIY folks. They could sell thie even cheaper but I guess this is a low volume product.
You are correct. At the time of the review I didn't have another internal resistance tester to compare to. I later reviewed a FNIRSI HRM-10: th-cam.com/video/qLrJt0llsJU/w-d-xo.html and did some comparison there.
AC conductance method will result in different results. I have another internal resistance meter coming and will do a comparison once I get my hands on that one.
You can use most DC loads with a scope and do the same test. Set the load to pulse the current (you can even put a small draw as a baseline), and observe the voltage on a scope. Pretty easy to get decent results. For coin cells, you can use a signal generator instead of the dc load - just be careful not to set it to charge the battery (although with a milliamp or less, really not a problem)
To accurately measure the batteries with 4 wire system, you must separate the probe tips with an insulator and touch the battery at 4 points. That's not what I have seen in the video.
The other well known IR meters use a 4-pin QX type aircraft connector, similar to what's used on Hakko soldering irons. Much bigger than the DB9 used here. I have one IR tester that is very slim and uses a standard USB type A plug and socket. The current is tiny so it doesn't matter about thin conductors.
"Take a look" (used in the USA) is the commonly used equivalent to "Have a look" (used in the UK). ... At least he didn't say *"off of"* instead of "from". 😢
Thank you for the review. I think it would have been nice for the tester to include a battery holder for the most common batteries seen today... perhaps with a few flexible holders for sizes that don't match. Not sure I can really appreciate this tester tho, without a "reference" standard to ensure that it is accurate.
Profit margins have to be very thin on these instruments. You’d think it would not be worth the extra cost in labor and equipment to obliterate the part markings. I wonder if it really slows down other shady Chinese manufacturers from cloning their intellectual property? It is going to make repair of this instrument more difficult, but on the other hand it is probably intended to be disposable rather than repairable anyway.
The parts will be delabelled before soldering, easy enough with a reel to run them through a laser to scan and erase the marking, and then stick a new top cover on, and reel them up again. Must be places that do this for money, you take them the reel, and get the erased one back.
Great review as always mate! The 4 wire method is heaps better; I like how you always explain the theory of the instruments.
@KerryWong thanks for the review looks like an interesting item i just got a YR1035+ for £20. ,, this IR502 is coming up as only £32 seems like amazing value,, could you please maybe review the Hanmatek DOS1104 ,, its £150 for a 4 channel Oscilloscope,, i appreciate and value your opinions
The people at Tooltop sure are militant about scrubbing off identification. Looks like they obliterated every semiconductor number and even sanded the frequency off of the crystal.
Sanding the crystal is pointless. Its easy to measure the frequency. Even cheap multimeters have frequency measurement.
Only reason is so no other chinaman copies the firmware and pcb design, reproduces the same product, but cheaper and destroys the original guys business that came up with it. Many such cases, sad. Still won't buy
Wow, I was just looking at one of these a few weeks ago. Thanks for the timely review.
@13:30 nice they have Rubycon caps in there.
If the capacitors aren’t counterfeit…. The capacitors could be fakes even if the manufacturer bought them in good faith.
If they were fakes, the brand would be Rulycon or Rudycon in the same font.
But why are they 200V caps. No battery is 200V.
@@TheDefpom Supposedly China is cracking down on trademark and intellectual property infringements. Sometimes I wonder how well that is enforced. In the past I have seen totally copied trademarks and the only way to tell is if the part does not perform to specification or if perhaps copy looks blurry or there is a misspelling somewhere else on the part.
@@simontay4851 Margin, they need low leakage, so used good capacitors, as this is likely how the AC test is coupled through.
Wonder how well protected it is against reverse voltage, and them giving the pinout means it is easy to make bespoke test lead sets as well.
I see the battery meter has a "rel" button. Accuracy might improve if you rel'ed it out.
Yes, every power up like clamp ampere meters in DC you should power on and wait a little, short/close the contacts together and then zero it to compensate any drift or error from leads
thankyou for the review
I did not understand, if the meter uses the Kelvin method for measuring resistors. You would think so, but I would have like to have seen that proven, one way or the other. Cheers.
Is that a security screw next to “V1” by the DE9 connector meant to discourage disassembly, or is it stripped by poor assembly?
Perhaps the reason the meter is giving you unexpected “resistance” readings for the 100 ohm resistor is that it is actually measuring impedance. Is that resistor wire wound inside?
At 1kHz, I would expect some deviations but not 1.5 Ohms. I had verified the reading with an LCR meter at 1 kHz.
I just tested some wire wound resistors between 50 and 680 ohms. The maximum error I got at 1 kHz was 0.5%. Equipment ET431 and error based on Zs/DCR. The impedance was always > resistance, as you might expect. Between using REL and switching to a Vishay rectangular precision resistor, I bet the measurement will have less than 1% error.
This is surely useful for the off grid freak to weed out lazy batteries. Say your house has a 48V system and 12V lights, you can arrange the batteries to feed the lights from strong batteries rather than waste inequality inside the BMS and use a converter to reduce 48V down to 12V. Mustool is offering cheap solutions for many DIY folks. They could sell thie even cheaper but I guess this is a low volume product.
This one is similar in price to existing products of this type and spec.
This is a few $ cheaper and has a colour vs monochrome screen.
Accuracy cannot be judged by this review. The accuracy (inaccuracy) declared here is only the subjective opinion of the reviewer.
You are correct. At the time of the review I didn't have another internal resistance tester to compare to. I later reviewed a FNIRSI HRM-10: th-cam.com/video/qLrJt0llsJU/w-d-xo.html and did some comparison there.
Interesting video, as always. If you had a chance to evaluate an ICharger S6, that might be an interesting topic.
Not having another meter to compare it to? How about some hand calculations using the formulas you reviewed.
AC conductance method will result in different results. I have another internal resistance meter coming and will do a comparison once I get my hands on that one.
@@KerryWongBlog That will be awesome, I'll look forward to it.🥰
You can use most DC loads with a scope and do the same test. Set the load to pulse the current (you can even put a small draw as a baseline), and observe the voltage on a scope. Pretty easy to get decent results. For coin cells, you can use a signal generator instead of the dc load - just be careful not to set it to charge the battery (although with a milliamp or less, really not a problem)
Couldn't you just use the ohms law method to cross validate the accuracy of the meter?
As mentioned in the video, the resistance measured by the AC conductance method is slightly different so not an apple to apple comparison.
@@KerryWongBlog I appreciate the fast response. I enjoy the reviews and product testing keep up the good work.
To accurately measure the batteries with 4 wire system, you must separate the probe tips with an insulator and touch the battery at 4 points.
That's not what I have seen in the video.
I mentioned that as well. Given the battery terminal types of the batteries it was nearly impossible to do that.
DB9, heh. Somebody has been digging in the trash pile.
The other well known IR meters use a 4-pin QX type aircraft connector, similar to what's used on Hakko soldering irons. Much bigger than the DB9 used here.
I have one IR tester that is very slim and uses a standard USB type A plug and socket. The current is tiny so it doesn't matter about thin conductors.
I'll rather burn 20bux than buy something what I can't fix
HAVE a look, not take.
"Take a look" (used in the USA) is the commonly used equivalent to "Have a look" (used in the UK).
...
At least he didn't say *"off of"* instead of "from". 😢
Interesting video. I think the add on banggood says it all. Thanks for your time and efforts.