trilerian

iTrader: (51)

Most devices out there that measure IR give unrealistic readings. This is a measurement done by DC load. I have a youtube video showing the measurement compared to HP 5.5 digit meter. Uses a 4 wire measuring method as well so the voltage sense leads are not affected by the current carrying leads.

gigaplex

iTrader: (2)

Ichargers use the balance leads for the voltage measurement so they're 4+ wires (depending on cell count).

Sabin

iTrader: (1)

Unrealistically high or unrealistically low? And by how much?

trilerian

iTrader: (51)

"Unrealistically" is kind of an embellishment. But the iCharger reads about half the IR that I am seeing when testing. But ultimately it is all down to equipment used to verify the testing and the code used. I can make the IR read whatever I want, but I try to verify that with other testing equipment.

And, if I am not mistaken, users of the GFX devices also say the iChargers read too low. But really, in the end it is all about whether or not the device you are using measures consistently for your batteries. If it reads consistently, then it doesn't matter if it is high or low. Unless you are comparing to someone else, but then that is where industry standards should come in. An industry standard in this case would be something like, measure the voltage at rest, put a known load on the battery, wait X amount of time, then read the voltage under load. I have found that a 200-250 millisecond delay is adequate. Less than 200ms and you can get really low readings. But this will depend also on the equipment being used to test.

Sabin

iTrader: (1)

See, that's a bit of a problem. It's about more than just consistently, it's about accuracy aswell. If your charger is showing a significant difference than calibrated test equipment, that's a good sign the charger has not been calibrated correctly, the firmware needs an update or, worst case scenario - the charger is faulty. Whatever the case may be, it shows the IR measurement readings cannot be trusted.

Roelof

Readings can never be trusted as long you are using connectors. Bad connectors and/or power leads can cause wrong measurements as well.

Sabin

iTrader: (1)

Another reason to use good quality connectors and have good solder joints.

malkiy

iTrader: (10)

I’ve had the 4010duo, 406duo and the dx8 ichargers. Also have had powerlabs chargers. My connectors are the tq wire strain relief plugs. i have yet to see a charger match the multi meter readings. In almost all cases it’s slightly below the multi meter reading.

EAMotorsports

iTrader: (79)

You are spot on sir!!!

I have been saying this for years! Anything over 125f on the case (putting cells internally at 140+) kills the cells, causes them to break down and IR actually increases. I have completely gone away from discharging and charging cells anymore.

I have custom computer controlled equipment at home that can discharge up to 800amps mainly for testing drag batteries. It plots a live IR curve as the pack is discharging and IR decreases until a certain temp and then it begins to rise as the cells become too hot.

EA