Campbell Scientific NL240 Wireless Network Link Interface - Manual (Page 56)

Appendix C. NL240 Settings
This setting affects the transmission power level of the NL240,
which may affect the transmission range of the device. This
setting does not affect the overall power consumption of the
device.
Lower Power Mode
If Low Power Mode is enabled, then the device will be put into its power
saving mode. At full power the device consumes approximately 0.6W when
idle and 0.7W when communicating (USB disconnected). Enabling Low
Power will result in significant power savings. The power savings and the
behavior of the device depend on whether it is configured to join an existing
network or create an ad hoc network.
Join an Existing Network
If the device has joined an infrastructure network and Low Power Mode is
enabled, approximately 1/2W savings are observed while communications
are idle and approximately 1/3W savings are observed when doing typical
communications (i.e. data collection from a datalogger). However, power
savings are affected by the amount of traffic on the network because the
Wi-Fi module has to wake up to receive broadcast traffic from the Access
Point. Therefore, power consumption may increase slightly on a busy
network.
In typical PakBus applications, overall communication speed is not
noticeably affected by enabling Low Power Mode. However, it may be
noticeably slower in some applications because in Low Power Mode the
Wi-Fi module is put in sleep mode and occasionally wakes up to receive
data from the Access Point. This does slightly reduce the responsiveness
of the device.
If configured to join a non-existent network or a network that is not in
range, the device will periodically (~50 sec) attempt to connect with the
network while going to a low power state in between attempts. This
behavior will be observed regardless of the Low Power Mode setting.
If the device has joined an existing ad hoc network (one which it did not
create), then it will stay on at full power while the network exists and is
active. Once the network has been taken down or gone out of range, the
device will power down the Wi-Fi and go back to periodically checking
for the network to come back in existence. This behavior will be observed
regardless of the Low Power Mode setting.
Create an Ad hoc Network
If the device is configured to create an Ad hoc network and Low Power
Mode is enabled, then it will periodically power the Wi-Fi on and off in
an effort to conserve power. If Low Power Mode is disabled, then the
device will keep the Wi-Fi on at full power.
The periodic low power behavior is governed by the two settings “Ad hoc
Low Power On Time” and “Ad hoc Low Power Interval.” The device will
periodically power on according to the time configured in the “Ad hoc
NOTE
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