Fnirsi HRM-10 battery voltage Internal Resistance tester

Batteries and Chargers Chargers
21

ahh. I miss understood.

1 Thank
22

I’m trying to adapt these “YR1035” style probes to my HRM-10, which are built similar to a battery clamp, with a middle sense pin.
I used a multimeter to check which pins on the connector are sense and current but the HRM-10 passes current through both circuits during testing, so I can’t determine the pinout. Can someone please check their battery clamp accessory for the pinout so I can finish this conversion? Thank you

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23

I ended up with this wiring

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In case of coaxial pins the inner one should be for resistance testing and the outer is for voltage (thinner penetrates oxide layer better).

UPD:

Or not. After reading TimMc’s findings and thinking I gues thinner pins (the inner ones) should be used for voltage sensing. Since both of the pins of your probes are crenulated it doesn’t realy matter.

2 Thanks
24

I checked continuity of the 18650 battery clamp accessory.

Pins with the notch at the top:
1 2
3 4

Pin 1 is connected to the positive outer pin.
Pin 3 is connected to the positive inner pin.
Pin 2 is connected to the negative inner pin.
Pin 4 is connected to the negative outer pin.

The wires might be connected to the wrong things on the negative side?

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2 Thanks
25

Tim’s battery stand/clamp changes the location, it uses the inner pin on the positive side and the outer on the negative side. I agree it’s probably not a big deal, but since the sense pin of the probe is the only spring loaded part and very small contact area, it will always have the same force on it and in theory make for more consistent tests.

I agree it might be wired wrong- I assume the bottom 2 pins on the connector are one of the pairs (like in Qubeet’s diagram), because I found that pair alone can be used to check the voltage of a battery. Maybe that means it’s the sense pair? The hrm-10 is passing 1khz on 4 different pin combinations to my DMM so I don’t understand how it works. I asked fnirsi support originally for the pinout and they tried to help but didn’t have enough info.

Thanks to both of you for the help.

1 Thank
26

I’m curious to see how these testers compare to each other:
FNIRSI HRM-10
Zoyi ZT-DQ02
Zoyi ZT-XC1
Zoyi ZT-XR1

I noticed the latest two in this video: