VB3i MANUAL
Page | 13
22 May 2014
Analogue inputs (A IN)
The VBOX3i contains four differential 24bit analogue input channels with a maximum sample rate of 100Hz. Each
channel has its own dedicated analogue to digital (A/D) converter with all four channels being sampled synchronously
to each other. The voltage range of the input channels is ±50volts. Note that unlike the ADC03 module, the analogue
channels in the VBOX3i are not electrically isolated from each other.
The analogue input connector also contains voltage outputs that can be used to power external sensors. These are a
Vbatt connection which is equal to the VBOX input voltage level and a 5V DC out connection which is equal to 5V ±2%.
The 5V out connection is internally protected by 350mA thermal fuse. The Vbatt connection is internally protected by
a 200mA thermal fuse on V2/V3 units, and 100mA fuse on V1 units. For connector pin configuration see page 16. A
screw-terminal connector block is available as an option for easy connection of signal pins.
Using the VBOXTools software, logging of the analogue channel data can be switched on or off. It is also possible to
change the name of each input channel and configure scale and offset values for calibration of sensors. A scale value
of 1 and offset of 0 correspond to a channel reading in volts DC. This means that the value stored on the compact flash
card for the channel will also be in volts. When using a sensor such as a load cell, it may be desirable to store a reading
in Kg. In this case, changing the scale and offset to suit the sensor data sheet allows the data stored onto the compact
flash to be in Kg. When changing settings for an analogue channel using VBOXTools software, a live data view of the
current channel is shown. The value shown is the value after scale and offset is applied and can therefore be used to
aid sensor calibration.
NOTE: The 5V regulated output on pin16 is only good for VBOX power supply voltages >8.5V
Using VBOXTools software, logging of the analogue channel data can be switched on or off. It is also possible to
change the name of each input channel and configure scale and offset values for calibration of sensors.
A scale value of 1 and offset of 0 correspond to a channel reading in volts DC. This means that the value stored on the
compact flash card for the channel will also be in volts. When
using a sensor such as a load cell, it may be desirable to store a
reading in Kg. In this case, changing the scale and offset to suit
the sensor data sheet allows the data stored onto the compact
flash to be in Kg. When changing channel setup for an analogue
channel using VBOX Tools software, a live data view of the
current channel is shown. The value shown is the value after scale
and offset is applied and can therefore be used to aid sensor
calibration.
500Hz logging
VB3i has the ability to log 4x analogue channels at 500Hz. With
this feature enable the file sizes will increase as a result.
When loading the VBO file into VBOX Tools ensure you are
running the very latest version as older versions are not
compatible with 500Hz data.
Note: A 25W D-sub to 4W BNC adaptor
block is available through your VBOX
distributor, part number RLVBACS054