Analogue Input

You can see the pinout information for the Analogue Input Connector here.

VBOX 4 contain four differential 24-bit analogue input channels with a maximum sample rate of 500 Hz. Each channel has a 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 ± 50 V.

The analogue input connector also contains voltage outputs that can be used to power external sensors. These are a Vbatt connection that equals the VBOX unit's input voltage level and a 5 V DC out connection that equals 5 V ± 2%.

• The 5 V out connection is electrically isolated, allowing for a current draw of up to 120 mA.
• The Vbatt connection is internally protected by a thermal fuse of 300 mA.

A screw-terminal connector block is available as an option for easy connection of signal pins.

By using the VBOX Setup software, you can change the name of each input channel and configure scale and offset values to calibrate sensors.

A scale value of 1 and an offset of 0 correspond to a channel reading in V 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 readings in kg. In this case, changing the scale and offset to suit the sensor data sheet allows the data stored on the compact flash to be in kg.

When changing settings for an analogue channel in the VBOX Setup software, you can see a live data view of the current channel. The value shown is the value after scale and offset are applied and can, therefore, be used to aid sensor calibration.

500 Hz logging

VBOX 4 units can log 4 analogue channels at 500 Hz. You can enable 500 Hz logging for internal analogue and digital inputs by clicking the 500 Hz logging for internal A/D toggle switch in the Logging menu in VBOX Setup.