USB Relay Controller and USB Relay Module

USB Analog and Digital IO Modules

LucidControl USB IO Modules

  • Data acquisition and control
  • Cost effective and flexible
  • Platform independent
  • Windows® and Linux
  • Compatible with RPi and Beagle Bone
  • Clippable on DIN-Rail
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  • Industrial & home automation
USB Digital Input Module

USB Digital Input Module

LucidControl Product Series

  • 4 / 8 digital inputs
  • For 5V, 10V and 24V signals
  • Opto insulated contacts
  • Counters and edge detectors
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USB Digital Output Module

USB Digital Output Module

LucidControl Product Series

  • Opto insulated option
  • 4 / 8 digital outputs
  • Relay module option
  • Pulse width modulation and timers
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  • Switching and power control applications
USB Analog Input Module

USB Analog Input Module

LucidControl Product Series

  • Measurement range options
  • 4 analog inputs
  • e.g. 0-10 V or 0-20mA
  • 14 bit resolution
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  • Acquisition of sensor signals
USB Analog Output Module

USB Analog Output Module

LucidControl Product Series

  • 4 analog outputs
  • Output range options
  • e.g. 0 - 10 V or 4 - 20 mA
  • 12 bit resolution
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  • 4 - 20 mA current interfaces
USB RTD Input Module for Pt100 / Pt1000 with 8 Channels

USB RTD Input Module

LucidControl Product Series

  • 4/8 Pt1000/Pt100 RTD inputs
  • Temperature range: -180 ~ 180 °C or 0 ~ 360°C
  • 0.1 °C resolution
  • Heat control applications
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  • Logging of temperatures

LucidControl USB Relay Module

LucidControl USB Relay Controller Module

Digital Output Module – USB Relay Module

LucidControl USB IO Modules is the unique product series for monitoring and controlling analog and digital signals.

The Plug-and-Play modules work with Windows and Linux and they are compatible with the popular Raspberry Pi and Beaglebone computers. For an easy integration a command line tool is provided as well as Java and Python API.

The DO4-S – USB Relay Module is one product of this series and it is able to control 4 Single Pole Double Throw (SPDT) relays.

The LucidControl DO4 USB Digital IO module is available in the following options:

Output Configuration Function
Solid State Relay The optical and potential insulated outputs are realized by using solid state relays (SSR). They provide the best overall capabilities for controlling power loads like pumps, fans or heating elements by statically switching or by periodically pulsing. Each output is rated with 30 V and 0.75 A and can switch loads up to 22.5 Watt.
SPDT Relay Using mechanical SPDT (C-Type) relay switches allows to switch or toggle signals e.g. for measurements without distortion.

This article concentrates on the SPDT Relay Type (DO4-S) of the USB digital io module and shows how it can be used for general purpose applications.

USB Relay Controller

Solid State Relays are the best solution for controlling power loads like lamps and pumps. They are able to control the power of a load by switching them on and off very fast using pulse-width modulation (PWM). Solid State Relays have a strong insulation and provide a very strong protection of the controlling computer.

In contradiction to the Solid State Relay Module, the USB Relay Module provides mechanical SPDT relay switches instead of semiconductors like transistors.

This allows the USB Relay Controller to switch power load like lamps, valves and fans as well as to control signals like temperature sensors or audio lines without distortion.

USB Relay Module as Audio Switch

USB Relay Module Switch

Mechanical relays provide also a very strong protection level to the connected computer because the switched signals are in a completely separate circuit and do not share signals. In the drawing the relay is highlighted gray and the galvanic insulation is indicated by the red line. This protects the control logic of LucidControl USB Digital IO Module and the computer from the switched signal.

An additional advantage is that SPDT switches can toggle between two signals. This means it is not only possible to switch a signal on and off but also to select between two signals. Take for example the selection of one out of two audio lines which are alternatively connected to a loud speaker as shown in the picture.

When the relay is switched off, the audio source, which is connected to the common contact “C” of the SPDT relay, is switched to the normally closed contact “NC”. When the relay is switched on “C” is connected with normally open contact “NO”.

Like all technical solutions mechanical relays have also their disadvantages. Because of having movable mechanical parts the number of cycles of the switch is limited and it is not possible (or at least not recommended) to switch the relays in a cyclic manor. This means that pulse-width modulation modes are not supported by the DO4-S USB Relay Module.

We hope we could give you an overview what you can do with the module. More information can be found on the USB Relay Controller Output Module product page.


Control of 4/8 digital output channels or relays

The USB Digital Output Module is the control solution for digital lines. The USB Digital Output Module allows the generation of high/low signals as well as to control power consumers.

USB Digital Output Module options

Please find here more information about the characteristics of the different USB IO Module outputs.

Digital Output operation modes

For most flexibility each of the 4/8 channels of the USB Digital Output Module can be configured on one of the following modes:

Mode Function
Reflect Mode Generates a digital output signal by setting the channels state directly.
Duty-Cylce Mode Generates a Pulse Width Modulation (PWM) by configuring cycle time and duty cycle.
This mode can be used in order to control the power of loads by pulsing them periodically.
On-Off Mode Generates a time sequenced output signal. Using this mode the USB Digital Output Module can be used to realize e.g. time switches.
Galvanic USB Isolation

All LucidControl USB IO Modules are available with galvanic USB isolation. Contact us for more information.

High speed output processing

The USB Digital Output Module provides functions which allow to access the outputs without direct interaction of the host computer. This allows a precise timing which would not be realizable if the host computer was involved.

Optical indication of digital output states

The state of each digital output is reflected by a LED

No Power Supply needed

All LucidControl are power supplied by USB and do not need additional power supply.

Easy installation of Hard and Software

LucidControl modules are easy to install and start working immediately after set up.
The IO Modules are compatible with Windows, Linux, Raspberry Pi and Beagle Bone
LucidControl provides drivers for all major operating systems. Command line tools and APIs for Windows and Linux are available. The API is ready for .NET, Java and Python.