thanks ! it’s better solution for me…
for me it’s two differente device
NAS-WR01Z = 3.96
NAS-WR01ZE=2.23.0
but all are this bug…
Yes, that is the same for me with the Z and the ZE, but in my case only the ZE with firmware version 2.23.0 has this bug
The neo coolcam plugs can send their kWh value because of the 2 reasons:
- the Report Threshold has been exceeded (configuration [49-112-0-9] Current Report Threshold)
- the Report Interval has been exceeded (configuration [49-112-0-7] Meter Report Interval)
I have a strong suspicion that the negative values are sent only in the 2nd situation, i.e. when the value is sent because the Ampere value in the device changed significantly (or at least more than the value configured). I also think that if the value is sent because the interval period ended, a correct usage value will be sent. This can explain why the plugs can send correct values for a long time (if no significant changes in the Ampere measurements are detected, it will not send the negative values) and all of a sudden can send the negative values (when a change in the electrical usage of the device connected to the plug was detected). It is my observation that plugs that have devices connected to them for which the usage varies little to none hardly ever send negative values, whereas plugs that have devices connected that vary a lot much more often get the negative values.
The default for the Current Report Threshold configuration is 50, which translates in 50 * 0.01A = 0.5A. A non-periodic report is sent every time the plug detects a change of at least 0.5A in the current drawn by the connected device. To test my hypothesis I am going to configure all of my plugs to send a report only if the connected device’s current changes more than 16A, so a configuration value of 1600. Since the maximum current these plugs can carry is theoretically 10A (2500W at 240V) and I for safety reasons I am not going to put a load on one that actually does take that much current anyway, that means that my plugs should not send the non-periodic reports anymore. The plugs should therefor only send their periodic reports at an interval as specified in the ‘Meter Report Interval’ configuration. The default for this is 300 seconds. I have good hope the plugs will not send the negative values any more with this configuration active. The only drawback of setting this configuration is that the values registered for Wattage, Voltage and Amperage do not get updated as often anymore and thus the values collected for these entities will be less reliable. Since I’m much more interested in the Usage (kWh) per device and I hardly ever look at those W, V and A values, I think I can get away with this.
My NAS-WR01ZE plugs have the same FW: v2.23.0, SDK: v6.81.3 firmware.
Ok, so my hypothesis wasn’t correct:
Even without the non-scheduled reports still the devices send both the extremely negative numbers and non-negative numbers.
Does this negative value mean something ? Such as a wrong value read/write and default make it return this fixed negative value ?
No, I don’t think the fact that the numbers are negative have any meaning. Common belief is that they are caused by 2 different bugs in the device’s firmware. One bug that causes the value to have it’s highest bit ‘randomly’ (or at least under unknown conditions) flipped, and another -less visible and less often occurring- that causes the value to suddenly increase by an unnatural growth. The first bug can be worked around, as the fault is easily detected plus the correct value can still be determined from it’s mangled form. The second bug is harder to detect, and it actually corrupts the values without -for at least as I know- a means to determine the correct value from it.