Powering the UTRED30-WiFi

The UTRED30-WiFi can be supplied from one of two power sources:

• via two AAA batteries

  The batteries have a life span of approx. 6 to 12 months, depending on the quality of the battery, log interval, frequency of reviewing data on the display and how often an alarm sounds.

  The batteries inside the unit will not be charged when external power is supplied.

  The remaining battery capacity indicator is tuned to Alkaline batteries. NiMH rechargeable batteries can be used, however the battery indication may not be accurate. Preferred batteries are alkaline.

  The battery cut-off voltage is initially set to 2.2V.

  A 4-bar battery indicator shows an approximate remaining battery capacity. If the batteries are full, this symbol will be shown:

  

  When the batteries are empty, this symbol will be shown, and the batteries require replacement.

  

  Please always replace both batteries with fresh ones at the same time. Replacing only one of the batteries with a partially charged battery will drain the internal backup battery.
  It is possible to use rechargeable AAA cells, however, please note that due to the different voltage the battery indicator will not show the correct remaining percentage, and the internal backup battery may drain faster. Rechargeable cells will deplete faster than Alkaline or Lithium batteries.

• via a commercially available 5V USB power supply (5W).

  When supplied externally, the power symbol shows on the display.

  

  Supplying the unit with external power allows you to use the internal AAA batteries as a backup should external power be unavailable.

  When you remove the external USB power the display briefly turns off.

  Some low-quality USB power supplies are unable to deliver sufficiently stable power to the UTRED30-WiFi. Please use a power supply from a reputable source that carries a UL or CE marking.

  If the logger detects an unstable power source, the power symbol will flash and the buzzer will sound.

  In this case, the logger will not be powered by the external supply, but remain powered by the AAA batteries instead. Please remove the supply and replace it with one of better quality.

  The unit can not record temperatures when powered from a computer USB socket.

  The unit should have overvoltage protection to 15V.