Analog Inputs (Vector) - Nortek Vector Comprehensive Manual

4.1

Analog Inputs (Vector)

There is an option to connect external sensors to the two analog inputs. The external sensors may
be powered by the Vector (enable this in the Deployment Planning dialog), and their data output may
be stored in the instrument during a deployment or downloaded in real time. With two external
sensors connected, the Vector is able to read both analog inputs at the same time.
The reported analog value from the Nortek instrument is counts. The scaling is V = (Counts/65536)*5
due to 16 bit AD converter. The input range is 0-5 Volt, where 0 Volt equals 0 counts, 5 Volts equals
65535 counts and 2.5 Volts equals 32768 counts.
The analog input can be scaled and re-labeled in the instrument specific software; Click View >
Analog Inputs.
To configure the Vector for use with external sensor:
In the instrument software click Deployment > Planning > Use existing or use Load from
Instrument.
Check the "Use Advanced Settings" box and go to the Advanced tab.
Define which analog input (1, 2 or both) to use.
There is a choice between fast and slow sampling. When choosing slow, the sampling is done
once a second together with the other non-velocity sensors. If fast is chosen, the analog sensor is
sampled together with the velocities at for instance 8 Hz. Only one Slow input is permitted.
If you want to power the external sensor from the instrument you must check the Output power
box.
The output power is configured in hardware by Nortek and can be raw (i.e. battery power), +5 V,
or +12 V (see table below). The raw setting is the default setting and all instruments come with this
setting unless otherwise was specified upon ordering.
Power out can be software selected by sending a HEX command in a terminal emulator.
Voltage Level
RAW
+12 V
+5 V
Be aware that the power out is turned off when the instrument is in sleep mode, as this contributes
to reducing the system's power consumption significantly. Consequently, the external sensor used
must be capable of automatically resuming its duties once the power comes back and it must do
this within 1 sec after power up in order to provide correct data for the first sample. Also note that:
Power at 5 and 12 VDC comes through switching regulators. This means that power drawn from
the battery pack is 15-18% greater than the power consumed by the external device. See example
below when considering energy consumption.
The output voltage is protected against short-circuit with a 1-amp fuse. To protect the Vector
circuitry against external sensors providing an output voltage in excess of +5.0V, there is a
clamping diode on the input with a current limiting resistor in series. The diode will conduct at
voltages above approximately 5.3V. To achieve stable conditions during testing, the +5V_SEN net
can be powered up from command mode by sending the hex command 435001C4.
The output voltage turns on at least 0.8 s before the beginning of a measurement interval, and it
turns off again at the end. The first measurement of the analog inputs occurs roughly 0.9 s after
power is applied.
The planning software does not consider power consumption of your external devices when it plans
© 2018 Nortek AS
Command
OPWRBA
OPWR12
OPWR5V
Integrators Guide - Light
Maximum Current
500 mA
100 mA
250 mA
91