cheap voltage tester for light battery packs

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https://www.ebay.co.uk/itm/18650-Lithium-Li-ion-Battery-Tester-Voltage-Current-Capacity-Detector-LCD-Meter/331806615506?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160727114228&meid=dfaca7dcf9fe460ab4bd9e71a2f95c96&pid=100290&rk=2&rkt=4&mehot=pp&sd=201305442842&_trksid=p2060778.c100290.m3507

you can set the voltage cut off and set it to what you like so 4.2v charged ie 5 bars and flat 3.3v cut off.


bit cheaper if you just want the pcb
https://www.ebay.co.uk/itm/18650-battery-Lithium-Li-ion-tester-Capacity-Current-Voltage-Detector-LCD-meter/400938078158?_trkparms=aid=222007&algo=SIM.MBE&ao=2&asc=49895&meid=624bf823886f4d1cad7bbcff88c7295e&pid=100005&rk=5&rkt=6&mehot=pp&sd=331806615506&_trksid=p2047675.c100005.m1851

 

[awol]

How do you set the voltages?
Also one of the pics shows a resistor between the 2 inner connections, is that needed?

 

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there is a button on the back hold it for 3 sec and goes to the low batt setting then wait 3 sec and goes to the full batt settings 1-30v for both.

that is just my 18650 charger just batt box meter then light.

 

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[awol]

Ordered one to try out. The resistor I mentioned is shown on the ebay pics connected to the 2 inner wire connectors but I think I understand it now, that is showing the load and the power to the 2 outer connectors.
Does it actually cut the voltage supply off when lower set level is reached?