Peripherals and Sensors for use with VELA

Along with the standard lab equipment that could be directly connected to the VELA, there were some dedicated hardware peripherals that could be used to interface the VELA to even more devices which are shown in the VELA Sensors, VELA Hardware and Software Extensions brochures, and also listed in the January 1989 pricelist.

There were two Sensor Adaptor Modules, the SAM1 and SAM4 which both required the SAM EPROM to be fitted to any VELA using them.

Sensor Adaptor Module 1 - SAM1

The Sensor Adaptor Module 1 was a stand alone box that connected via cabling to the VELA unit. Up to four SAM1 units could be connected to a VELA to provide the same functionality as the SAM4.

The SAM1 was battery powered and could be connected to the VELA or other devices such as a chart recorder directly providing some extra flexibility in data capture uses when compared to the SAM4 which depends on being connected to a VELA.

Sensor Adaptor Module 4 - SAM4

The SAM 4 was connected to the VELA by plugging it in to the Pulse trigger and channel connectors on the left hand panel of the VELA. The unit then allowed specialist sensors to be plugged directly into the module or separate channels to be used on the "pass through" ports again on the left hand panel. It was previously marketed as the GpSM.

The pass through connectors on the left of the SAM4 allowed all the normal experimental devices to be attached to the VELA so once fitted, there was no need to remove the SAM4 from the VELA.

On the rear of the SAM4 are the power connections and quick blow fuse holder.

Once connected, the SAM4 provided much more connectivity for the VELA with many sensors being manufactured for it. and the VELA below is shown with a Temperature sensor adaptor and 150deg C temperature probe.

The SAM4 provides a pass through power supply and comes with an uprated PSU. Power is connected to the SAM4 and chained to the VELA unit to power both devices from one single supply.

Sensors for the SAM1 and SAM4

Sensors for the SAM1 and SAM4 were interchangeable allowing the same sensors to be used in a wide variety of data capture settings and employed an industry standard connector.

Probes and other devices were then connected to the sensors to provide the final stage of the monitoring interface with the environment. The picture below illustrates a temperature probe and magnetic field probe.

The connectors on the rear of the adaptors are keyed 11 pin connectors

Types of sensor that could be connected to the SAM units include:

• Temperature
• Light
• Voltage
• Magnetic field
• pH
• Pressure
• Position
• Strain Guage
• Oxygen
• Pulse units
• Motion

Magnetic field sensor

The magnetic field sensor and probe could be used to detect and measure the presense of a magnetic field. By passing the probe over a magnet, the field could be measured as it gets stronger and weaker depending on the position of the probe to the magnet.

The magnetic field sensor and probe was developed to measure fields in the range of +/-25mT.

In conjunction with the probe and sensor adaptor, the VELA could be connected to an electromagnetic coil which is used to measure current as a magnetic object passes through, inducing a small current as it goes.

The coil can be seen in use in the photo below which was part of the StatPack software's sales brochure.

By passing a magnet such as the ones below through the coil, a small current would be created by induction which is then measured by the VELA.

The magnets are of a standard Alnico construction as indicated on the box that contains them.