I will try to answer these questions in a few steps.
I will gradually edit and update this message.
I’ll cite later, I’ll probably add them under spoilers. Karloson @ 11/18/18 09:48
bl0nde @ 11/18/2018, 00:53 *
Example:
Set 1 HIDANCE 12 in 1 + 2 * 10W Resistor for 377r
Set 2 HIDANCE 9 in 1 + 4 * 10W Resistor for 473r
Sobsno need to check a bunch of cables, adapters, the capacity of several banks, smartphones and tablets.
So I do not understand what I need in the end.
Suitable for testing banks, batteries and smartphones / tablets batteries, but not for testing cables - they do not have micro and / or bluetooth inputs.
bl0nde @ 11/18/18, 10:10
And what about the load?
I saw three types available:
1. 2 * 10W Resistor or 4 * 10W Resistor
2. RD Load resistor 15w or HIDANCE Load resistor 35w
3. RD LD25 LD35 or RD HD25 HD35
bl0nde @ 11/18/18, 09:55
[email protected], 09:48 *
Suitable for testing banks, batteries and smartphones / tablets batteries, but not for testing cables - they do not have micro and / or bluetooth inputs.
There are adapters for this, although there will also be losses on them.
It turns out to be better to take the option above, but the one that is simpler:
HIDANCE 12 in 1 + HIDANCE Load resistor 35w
1st part
Initially, we formulate the problem:
Initially you need:
Sobsno need to check a bunch of cables, adapters, the capacity of several banks, smartphones and tablets.
So I do not understand what I need in the end.
Those. tasks to solve:1. Measurement of large containers (telephones, banks)
2. Measurement of resistance of cables and, possibly, adapters.
Cable type assume the most common Micro USB & Type CWhat else makes sense to clarify:
Tasks that are not mentioned, but that affect the selection of equipment:1. Not mentioned the need to measure the capacity of small batteries. We believe so far that we do not need greater current accuracy.
2. Not mentioned the need to work with fast charging modes QC2 / 3, etc. We believe so far that working with these modes is not required. Ie we think so far that work with increased voltages 7-9-12 -...? 25? B is not needed. Also for this reason, we believe that the very same "triggers" of the load that allow the load to pretend to be "smart" are not needed
3. Not mentioned the need to check the limits of the operation of networked chargers as such. On the basis of PP.2 and 3, we believe for the time being that loads greater than 10-15 W (2-3 A at 5 V) are not necessary.
4. Not mentioned the need to check the limit operation
* multiport * network chargers and banks, when checking the total possible load on several ports at the same time (that is, when the source has two or more large loads simultaneously). We believe so far that the second tester is not mandatory for us.
2 part. So, according to Part 1, it turns out that the case seems to be relatively simple.
Complication - only the desire to measure the resistance of cables.
That is, in order to cover the problem of measuring resistance, we need some of these options:
Option 1:Tester with built-in resistance measurement mode + almost any load, including discrete. But to increase the accuracy of measuring resistance, it is still better to smoothly adjust the load (as we found above in the topic - instructions for measuring resistance, for example, the UM34 tester asks to adjust the current at the second stage of measuring resistance exactly to the value obtained at the first stage)
A tester is needed with those additional micro usb / type c input connectors that correspond to cables whose resistance we plan to evaluate.
Option 2:Two almost any testers + almost any load, but better regulated so that when measuring cable resistance we set a load current exactly 1A (then the resistance can be considered in mind by subtracting the output voltage from the input voltage ... otherwise you will have to use the calculator to make the difference divide by amperage :))
Here at least one of the two testers also need micro usb / type c input connectors
Option 3:Almost any tester + adjustable load, which is built ammeter and voltmeter.
Here, we also need micro usb / type c input connectors, but not with the tester, but with adjustable load.
Resistance will be calculated in the mind or on the calculator by the voltage difference between the input (tester) and output (load) divided by the amperage.
(I do not have such a load with a voltmeter and an ammeter ... there is no experience ... theoretically a problem is possible if the voltmeter in the load is not very accurate)
About adapters Immediately here let's talk
Their use to determine
absoluteCable resistance values ​​are not very desirable.
Almost all adapters make a very significant increase in resistance.
They can increase the estimate of resistance by 1.5-2 times, judging by my attempts to determine the resistance of the adapters themselves. The best figure I remember for adapter resistances was about 0.05 ohms. And the best cable I came across was about 0.12 ohms ... Ie added an adapter - made 40% error
But ... if the task allows us to reformulate it into "comparing different cables by resistance and identifying the best ones" (let's call it "
relative"measuring resistance), then the adapters will prevent us only to compare the resistance of different types of cables (compare micro usb cables with Type c, for example).
Those. it can be understood that this cable with connector X together with an adapter has less resistance than another cable * with the same connector X * and the same adapter (since the resistance of the adapter used can be assumed constant)
3 part
... in the editing process ... Consider specific options
bl0nde @ 11/18/18, 01:11
VitaliyK @ 12.10.18, 18:07 *
b) “Well, all-inclusive”: one main accurate USB tester is more expensive, one auxiliary USB tester is simpler; one electronic regulated load is more expensive; one load is simpler with fixed resistance values
Call it
Option A: Immediately for reference, write down the price tags (on 2018-11-18) of the components upon delivery to the Russian Federation with tracking
UM34C + HD35 - $ 30.99
RD AT34 - $ 9.99
RD Load resistor 15w - $ 6.46-6.84
Does this "maximum" set the tasks - yes.
Advantages:This kit will allow you to solve all the additional tasks that I listed above after the phrase
Tasks that are not mentioned, but that affect the selection of equipment:. BUT! It is important that you need to choose the option in the first position with the load of HD35, and not LDxx, because it supports fast charge trigger mode (in the description of HDxx there is a phrase “Quick charge trigger mode - QC2.0 5V 9V 、 12V 、 20V, QC3.0, FCP, AFC9V”, it’s not written about the load LDxx)
Resistance can be measured even with four connection options, since We have three voltmeters - a UM34 tester, a voltage difference between two UM34-AT34 testers and a voltage difference UM34-HDxx or AT34-HDxx
Disadvantages:The price tag is not at all humane - $ 47 for 2 testers 2 loads ... There is a feeling that these prices are currently slightly overestimated, 10% percent ... I am guided by the price of UM34C - now it is declared $ 19.99.
I bought the UM34C at a sale on August 29 like this: 986.61 rubles for the Central Bank / or $ 14.64 (17.94 price -3.30 coupon AliExpress (5/25))
Those. even without a coupon, the price used to be $ 17.94
Probably no need to hurry, you must wait for coupons, etc. :)
Call it
Option B: or easier option:
HIDANCE 12 in 1 + HIDANCE Load resistor 35w + HIDANCE 9 in 1 + 2 * 10W Resistor
/... Option B - while delayed ... in the editing process ... / Separately asked questions
bl0nde @ 11/18/18, 01:53
As far as I do not understand the difference in price between the RD UM25C and RD UM34C due to the presence of the first port OUT Type-C?
Are there functional differences?
I have both of these testers.
The main differences (UM25C / UM34C), except for the additional output connector for the product description:
1. maximum current - 5A / 4A
2. voltage readings, decimal places - 3 (0.001) / 2 (0.01)
3. current readings, decimal places - 4 (0.0001) / 3 (0.001)
4. Type of USB ports - (USB2 / USB3)
What I noticed myself
N + 1. At low currents (2-3 mA) there is a feeling that the UM34 is grafting.
(I have a backlight on one magnetic charging cable - its consumption for UM25C is 2.4 mA, and for UM34C it is 1 mA ... it may, of course, lie for UM25C, but this is less logical)
And what is the difference RD HD35 vs RD LD35
I have neither one nor the other. But, judging by the description, a trigger is built into HDxx that allows you to simulate a load that is compatible with different standards of fast charging, which is not in LDxx
/... "Minimum optimal set" - while delayed ... in the editing process ... / Well, the question to:
VitaliyK @ 12.10.18, 18:07 *
a) "Minimum optimal set": USB tester; adjustable load; we will find the rest in stocks.
Example:
Set 1 HIDANCE 12 in 1 + 2 * 10W Resistor for 377r
Set 2 HIDANCE 9 in 1 + 4 * 10W Resistor for 473r
Sobsno need to check a bunch of cables, adapters, the capacity of several banks, smartphones and tablets.
So I do not understand what I need in the end.
Post has been editedVitaliyk - 19.11.18, 00:11