Gocator Digital Output

What type of digital output does the Gocator support?

Each Gocator has two optically isolated digital outputs. Both outputs are open collector and open emitter, which allows a variety of power sources to be connected and a variety of signal configurations.

An open collector and open emitter functions like a transistor with the collector and emitter disconnected:

How do I connect the Gocator digital output to a PLC input?

To connect the digital output of a Gocator to an input of a PLC will require the collector and emitter (out_1+ and out_1-) to be connected to a voltage source. This can be done in two ways, a non-inverting and an inverting circuit. 

Non-Inverting:

*Out_1+ and Out_1- nodes are physically connected. The nodes are left in the circuit schematic to convey the Gocator pin connections.

Inverting:

*Out_1+ and Out_1- nodes are physically connected. The nodes are left in the circuit schematic to convey the Gocator pin connections.

In both circuits, the value of the resistor can be calculated by taking the supply voltage and dividing it by the desired maximum current through the Gocator (LMI recommends 2.5 mA, but up to 40 mA is possible).

Digital Output Specifications

How do I directly connect the Gocator's output to a source that draws more than 40 mA?

There are too many approaches to solve this problem for a single article. The most important takeaway from this section is that the Gocator's digital output can only handle a maximum of 40 mA. The image below shows a common application where it is required to actuate an electromechanical relay.

This circuit uses a power MOSFET to handle the input side load of the relay.

Of course, a solid state relay can be used to switch larger loads while reducing the complexity of the above circuit. Such a solid state relay must be chosen to meet the 40 mA requirement of the Gocator, and the circuit would look more similar to that of the PLC input.

How do I mount a resistor in an industrial cabinet?

While there multiple ways to do this, one simple solution is to utilize a DIN rail component block terminal such as the Phoenix Contact 2775249 or similar.