The Industrial Dual Relay Bricklet can be used to extend the features of Bricks by two relays. Each relay has three terminals such that the terminal in the middle is electrically connected to the terminal left or right depending on the state. The state is visualized by a LED. The Bricklet is equipped with
You can use this Bricklet to switch power supplies, motors, lamps, etc. Consider the maximum voltage and current.
If you want to switch inductive loads, please see: Inductive Load Switching.
Terminals and contacts are not insulated. If you want to switch higher voltages, consider to put the Dual Relay Bricklet in a casing. Touching the contacts is potentially life-threatening!
This Bricklet ist not galvanically isolated to the Tinkerforge system. This means that there is a direct electrical connection between the terminals of the Bricklet and the rest of the system. Dependent of the application this can lead to undesired connections, ground loops or short circuits. These problems can be prevented by using the Bricklet together with a Isolator Bricklet.
The Industrial Dual Relay Bricklet has a 7 pole Bricklet connector and is connected to a Brick with a 7p-10p Bricklet cable.
27mw (5.4mA at 5V)
+ 350mw (70mA at 5V) per activated relay
|Dimensions (W x D x H)||40 x 40 x 25mm (1.57 x 1.57 x 0.98")|
Each relay has three connectors: A, SW and B. SW is connected to A or B depending on the switching state of the relay.
To test a Industrial Dual Relay Bricklet you need to have Brick Daemon and Brick Viewer installed. Brick Daemon acts as a proxy between the USB interface of the Bricks and the API bindings. Brick Viewer connects to Brick Daemon. It helps to figure out basic information about the connected Bricks and Bricklets and allows to test them.
Connect the Industrial Dual Relay Bricklet to a Brick with a Bricklet Cable.
If you connect the Brick to the PC over USB, you should see a new tab named "Industrial Dual Relay Bricklet" in the Brick Viewer after a moment. Select this tab. If everything went as expected the Brick Viewer should look as depicted below.
After this test you can go on with writing your own application. See the Programming Interface section for the API of the Industrial Dual Relay Bricklet and examples in different programming languages.
Play around with the two relay buttons, you should hear the relay switching when toggling the buttons. An LED indicates the current state of each relay.
Without external components the switching of inductive loads can cause interference in the system that can lead to malfunctions or destroyed components. Typical examples for inductive loads are motors and solenoids, but these problems can also occur when switching e.g. fluorescent lamps.
If you want to switch an inductive load you need external components, e.g. a varistor or a combination of a resistor and a capacitor parallel to the load.
More information about protection circuitries can be found here.
A laser-cut case for the Industrial Dual Relay Bricklet is available.
The case of the Industrial Dual Relay Bricklet is delivered including cable ties for a cable relief and WAGO connecting clamps to join wires. The case is big enough to accommodate the cable relief as well as the WAGO clamps.
The internal construction can look as follows (with one as well as two relays connected)
The protective conductor (brown) is switched with the Industrial Dual Relay Bricklet. The external conductor (green-yellow) and the neutral conductor (blue) are coupled with the WAGO connecting clamps.
It is important that the external conductor is longer then the other cables. This way it is assured that the external conductor will be pulled of at last if the cable relief is overstrained or defect. We recommend the following length for the cables and the stripping:
The assembly is easiest if you follow the following steps:
Never work inside the case when components are carrying voltage!
The exact position of each part can be seen in the following exploded assembly drawing of the Industrial Dual Relay Bricklet case:
Hint: There is a protective film on both sides of the plates, you have to remove it before assembly.
See Programming Interface for a detailed description.
|Visual Basic .NET||API||Examples||Installation|