Replacing PSU501 battery - BWS500

BWS500 Maintenance Guide

Document code
Document type
User guide
Figure 1. PSU501 battery parts
+ terminal
Cable connector plug
  • 7‑mm socket wrench
  • 5‑mm flat head screwdriver or Pozidriv screwdriver (PZ2)

Vaisala recommends that you replace the battery every 3 years. The battery may need to be replaced more often if the conditions require, for example:

  • When operating in an environment where the ambient temperature is regularly very high.
  • When the station runs only on solar power, that is, the battery is intensively used.

You can check the battery status and state of charge through the remote monitoring service for stations connected to Vaisala cloud. Battery status is also available in the PODS‑MQTT interface.

The backup battery does not have any replaceable parts.
WARNING Do not replace the battery with a battery of an incorrect type. If you do, there is a risk of deflagration. Dispose of used batteries according to statutory regulations.
  1. Disconnect the power cable.
  2. To remove the PSU501 top cover, unscrew the fastening screws (6 pcs) and lift the cover.

    Use either a 5‑mm flat head screwdriver or a Pozidriv screwdriver (PZ2).

  3. To remove the PSU501 inner cover, unscrew the M4 nuts (5 pcs) and lift the cover.
  4. Carefully lift up the battery and remove it from the enclosure.
  5. Disconnect the cables (red and black) from the battery terminals.
  6. Connect the cables to the new battery.
  7. Put the new battery in the enclosure.
  8. Wait for a while, and check that the status LED on the component board is blinking green every 10 seconds.
    A red LED indicates a failure. If the LED is constant red, disconnect and reconnect the battery. If this does not help, contact Vaisala.
  9. Put the inner cover back in place.
  10. To fasten the nuts, first turn each nut a few rounds one by one. Then tighten the nuts hand-tight.
  11. Put the top cover back in place.
  12. Tighten the screws until the cover makes good contact with the surface of the enclosure base.