SDT 5000 User Manual
Document MBUD-0109v11
8. POWER MODES
The SDT 5000 provides several power modes each with a different features and power consumption
requirements. The power modes are: Power off, Continuous, Standby, and Polled.
Power off mode allows the SDT 5000 to draw very little current. The SDT 5000 will exit power off
mode by asserting the ignition line. Power off mode is requested by deasserting the ignition line. The
SDT 5000 is not running when in power off mode and must be powered on with the ignition line to
resume operations. All RTU data will be ignored when in power down mode.
Continuous mode allows the SDT 5000 to operate in full power state continuously with satellite
communications enabled at all times. The host and RTU can send data at anytime.
Standby mode turns off the SDT 5000 satellite receiver to draw much less power. The satellite
receiver can be configured to power on with a configured schedule or based on RTU requests.
Polled mode cycles the power on the satellite receiver such that it is always on long enough to be on
during one of the protocol retries. Effectively this is a combination of continuous mode and standby
mode. Similar to continuous mode the host and RTU can send data at any time. The difference
between continuous mode and polled mode is that in polled mode there is additional latency for both
RTU to host and host to RTU communications. Polled mode will draw on average less power then
continuous mode but more than standby mode.
8.1 Power
Off
Mode
The SDT 5000 can be requested to power down when the ignition line is deasserted. The SDT 5000
can be kept powered on without the ignition line asserted for a user specified time. See ‘alive’
command for details on setting this value. The ‘
keepalive’
command will display the facilities that
are keeping the unit powered on. The SDT 5000 is not running when in power off mode and must be
powered on with the ignition line to resume operations. All RTU data will be ignored when in power
off mode.
The following facilities will keep the SDT 5000 awake after ignition is dropped:
•
Keep alive timer,
•
User login to test port,
•
DTR asserted (Operating mode dependant).
8.2 Power
Mode
Configuration
The ‘
satcfg opmode
’ command is used to configure the power mode. This command requires access
to VAR privilege level.
>satcfg opmode
CONTINUOUS
Version 1.1, 03/24/06
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