For GRD-2G only

Power supply and inputs / outputs

Below you will find the minimum and maximum admissible values of digital inputs and outputs as well as analog voltage and current inputs, and also GRD consumption and power supply.

Power supply

Digital inputs

To activate the digital inputs a continuous voltage must be applied externally. This source of power has to share the GND terminal with the power supply of the equipment. If necessary the same power supply that feeds the GRD can be used. The input is of a Sinking type. It accepts sensor or PNP Sourcing type devices.

(1) GRD3301-XF, GRD3305-XF/ (2) GRD3534-XF

We now show two examples of how to connect an input, directly from the same source feeding the equipment and from an external source where we can clearly see that they must share the common Terminal.       

Digital outputs

Digital outputs are of the open collector type. The load to be connected must be fed with an external power supply and they have to share the GND Terminal with the equipment power supply. If necessary, the same power supply used to feed the equipment can be used.

The output type is NPN Sourcing type (Open collector).

Digital outputs to actuate a Relay

When the digital output is used to actuate a relay coil a protection diode must be added to the connection to avoid damage to the output of the equipment. This must be connected in reverse, that is the anode to the output terminal of the equipment and the cathode to the positive terminal feeding the relay. The relay must be fed using an external power supply, sharing the GND terminal with the power supply of the equipment, or if necessary the same power supply feeding the GRD can be used.

The following graph shows how to connect a relay to a digital output of the equipment.

Analog Inputs

Analog inputs refer to the GND Terminal of the equipment, consequently, the power supply used to feed the sensor must share the GND terminal with the equipment.

Voltage inputs (0-10V / 0-1V)

The following two examples show how to connect and analog voltage input for a single power supply or for independent power supplies.

 

 

  

Current inputs (4-20mA)

The following two examples show the connection of a 4 – 20 mA sensor sharing the power supply with the equipment for passive sensors or for active sensors with independent power supply.

2019-11-28