Solved! Foxwell BT715 Reads Different Values When Testing Start-Stop AGM Battery

Do you have the matter to check Start-Stop AGM battery using Foxwell BT715 battery analyzer? If it shows the various values after testing, how does one solve it? Here will share the answer offered by foxwelleshop.com engineer for this problem.

Let’s see the precise problem encountered by one among our customers.

Hi,

I received the Foxwell BT715. I opened the package and therefore the quality looked good.

I tested my FIRST vehicle (with almost new AGM battery):

All looks well except SOC=65.

These are the readings:

VOLTS 12.32

MEAS 774

RATED 760

SOH 100

SOC 65

RES 3.9

VOLTS 11.09

TIME 1.02

NO LOAD 14.01

LOAD 13.85

I now tested my SECOND vehicle (start-stop with older AGM battery):

I got SOC=40. I decided to do a second test. The SOC=81.

These are the 2 readings:

VOLTS 12.17 12.45

MEAS 565 581

RATED 650 650

SOH     88 90

SOC     40 81

RES     5.32 518

VOLTS   10.44 10.74

TIME    0.74 0.62

NO LOAD 14.23 14.68

LOAD 14.15 14.19

Why are two readings above so different, especially SOC?

Also, the BT715 never detects when I REV the car...

1.The second test was done immediately after the primary test.

2.I ended the primary test (turned off the load, turned off the ignition) then within a moment approximately I started the second test.

I didn't do a second test on the primary car but i think the SOC measured on the primary car may are inaccurate.

And is it normal for the BT-715 to NOT recognize once I REV the engine?

It is not ideal, because I even have to attend until the device times out, then it prompts me to pick the enter button once I do REV the engine.

I guess my question is why do i buy different leads to consecutive tests?

I do notice that the crocodile clips aren't large enough to grip my terminal directly so instead I grip it on one among the nearby bolts.

Foxwelleshop.com engineer replied as below:

1.For the matter why the values read out are different:

I have noticed that both the values of voltage and CCA have gone up. If the battery is within the car, it'll be charged when starting the car, the SOC also will go up, a bit like your telephone does when it's charged, the battery will go up. It ONLY can test the charging performance of the vehicle.

When you want to check the car (start-stop with older AGM battery) for quite just one occasion, you ought to await the car to chill down completely and therefore the value tested are going to be accurate.

2.For the matter BT-715 cannot recognize when REV the engine:

You should connect the clamps of Foxwell BT715 to the corresponding terminal of auto battery. don't clamp on the extension wire! Otherwise it'll affect the results of the test and should not detect the engine!

For example, in BMW vehicle, the battery is within the trunk, and lots of customers clamp it directly on the 2 electrode bolts within the engine compartment, therefore the value tested also will not be accurate. 

The bonding wire of the vehicle is additionally attached to the grounding terminal of the many electrical appliances, so it's easy to be disturbed.

Hope it helps you! 

Source:http://blog.foxwelleshop.com/how-to-solve-foxwell-bt715-reads-different-values-when-testing-start-stop-agm-battery/