[Nut-upsuser] blazer_ser battery.high / battery.low

Charles Lepple clepple at gmail.com
Thu May 29 03:21:40 UTC 2014

On Apr 29, 2014, at 5:30 AM, Andreas Lausch / TBT wrote:

> Hello list,
> we've got a PowerWalker VI 1000E/RT LCD UPS and like to use it with NUT
> using the blazer_ser driver.
> For the blazer_ser driver to display percentage, one has to add
> battery.voltage.high and battery.voltage.low voltages to the ups config.
> Here's what I received from the powerwalker customer service:
> Battery-Low Voltage: 21.6VDC
> Battery Shutdown: 19.2VDC
> Now my questions:
> 1. should the blazer_ser's high voltage be the voltage during charging
> or right after I've unplugged it from the mains?

sounds like during charging (or more accurately, during float charging at the end of the cycle):


> 2. should the blazer_ser's low voltage be 21.6V (Low) or 19.2V (Shutdown)?

From the calculations, I would guess 19.2V. In general, the LB signal comes when the battery is around 30%, so that there is still some charge left while the load is powering down.

> 3. Is there any way I can submit the high/low values, so they get
> integrated into the driver or doesn't blazer_ser support voltage presets
> per model?

It doesn't look like it.

Also, the blazer* drivers are no longer maintained, and are being replaced by the nutdrv_qx driver (which uses very similar code for these calculations, but the model-specific code is organized differently).

A comment in qx_initbattery() implies that some UPSes can provide the battery voltage range. You might try that driver (available in 2.7.1 and later) to see if it does this automatically. If not, you can check with the driver author to see about integrating some per-model defaults.

Charles Lepple
clepple at gmail

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