# Network and distributed acquisition using Dewesoft NET

With Dewesoft NET, your measurement system can be controlled remotely with the ease of use you couldn't imagine before. Dewesoft NET also serves as the center for Distributed Data Acquisition systems where you have multiple systems located either together or scattered across an entire continent. IRIG and GPS time will take care that data will stay synchronized, no matter how long the acquisition runs.

## What is Dewesoft NET?

Dewesoft NET application module provides a nice way to acquire data over the network. This allows us to use multiple systems as one instrument or to acquire data from different locations.

Dewesoft NET application module allows one or more measurement units to be under the control of other computers, named clients. The measurement units and clients must be connected via TCP/IP.

It is important to note that while any channel can be viewed on the clients, the actual data is stored on the measurement units.

Working with Dewesoft-NET is comprised of three basic steps:

• NET setup - network configurations, appropriate hardware and Dewesoft-NET setup (setting up client and measuring unit, remotely controlling a slave measurement unit)
• Measurement - creating a display, measuring and acquiring data, and storing this data on a network.
• Analysis - analyze acquired and stored data on the network, export measured data.

Image 1: Setup the equipment, connect over the Dewesoft NET and start measuring

## Which are the Modes of Operation?

Dewesoft NET offers three modes of operation:

 Mode Number of Measurement Units Number of Clients 1:1 1 1 X:1 multiple 1 1:X 1 multiple

With these three modes, almost any application can be covered - from single-channel expansion over the remote control to distributed measurements over hundreds of kilometers - everything is possible.

## 1:1 Mode - Single measurement unit and a Single client

Image 2: 1:1 operation mode for Dewesoft NET

1:1 mode works with a single measurement system and a single client. In this mode, there are two types of operation

 Types of operation Description Full remote control The client computer acts like a master of the measurement system. When controlling client changes to the setup screen, the measurement system also changes the setup screen. View only The measurement system acquires data, while the client computer can connect to it and view the "live" data, but it cannot control the measuring system. A "view client" can only look, but not 'touch'.

## X:1 Mode - Multiple measurement units and a Single client

Image 3: X:1 operation mode for Dewesoft NET

Multiple measurement systems and a single client are used in the case of distributed measurements or too high acquisition rates to be managed by a single measurement unit.

The measurement systems have to be synchronized either with hardware clock (one unit is the clock master, the others are slaves) or with the external clock source that is either IRIG or GPS. All measurement systems have to run with the same acquisition rate, in this case, only one connection option is possible - the client is always the master.

Master client starts and stops the measurement on all units in the measurement network. At any time, the client has access to view mode - but only to one measurement system (one-to-one connection like in single measurement system & single client configuration). Additional view devices are possible, but they can access only a single measurement system.

## 1:X Mode - Single measurement unit and Multiple clients

Image 4: 1:X operation mode for Dewesoft NET

The third network configuration is to have a single measurement system controlled by one 'master' client and additional 'view' clients.

The master client is able to change the measurement system setup, storing strategy, start and stop measurements, and much more. The view clients are only allowed to take a few channels from the measurement unit (up to the bandwidth limitation) and view and store the data on their local hard disk.

## Which Connection Types can be used?

The NET system is always connected via ethernet protocol. This can be obtained in several different ways:

 Ethernet protocol connection Type Description / Specialty Point to point connection It is the easiest and most simple configuration of the NET system. On either side, you have a computer (S-box, Minitaur, PC, laptop, ...) with a measurement device (DEWE-43, Sirius, ...) or without it.With point to point connection, you have an ethernet cable between those two devices. You have to manually set the IP addresses on both sides. Router Local network LAN The only limitation is the connection speed. Internet - Wired Dedicated TPC/IP ports need to be opened. Internet - Wireless

With the point to point connection, we connect two devices with the ethernet cable. We just have to manually set the IP addresses on both sides.

In order to do that, we have to go to Control panel -> Network and Internet -> Network and sharing center.

Image 5: Open Control Panel and select Network and Internet

We need to select Change adapter settings.

Image 6: Select Change adapter settings

Right-click on Local connections and select the Properties.

Image 7: Right-click on Ethernet local connection and select the Properties

In Properties, we choose Internet Protocol Version 4 (TCP/IPv4) and type in the IP address.

Image 8: Select the Internet Protocol Version 4 (TCP/IPv4) and click on the Properties button

IP addresses on devices must be the same, except for the last number, which must be different (ex. IP address on the first device 192.168.10.1, and the IP address on the second device is 192.168.10.2).

Image 9: Type in IP address

Now we can connect with the device in Dewesoft X software, measure, and collect data from it.

## How to Configure and Connect a Measurement Unit?

There are several possible configurations and setups:

 Unit Configuration options Description Standalone Unit Not networked to anything (the default setting of Dewesoft X upon installation). Slave Measuring Unit Can measure data under either local control or under the control of a master client. Mater Measuring Unit Can both measure data and control other measurement units (optional). View Client Can view data being recorded on the measurement units, but cannot control them. Master Client Can control the measurement unit(s) and view their data.

Each measurement unit must be configured as a slave measuring unit in order to utilize the Dewesoft NET software – however, if you are going to use one of your measurement units as the controller for the others, then you should configure that one unit as a master measuring unit.

It is not possible to have more than one "master" within a single Dewesoft NET system, in order to avoid confusion and conflicts.

## Searching for the Measurement unit

To activate the appropriate mode for each system within the Dewesoft NET, first run the Dewesoft X and open the Settings menu.

Image 10: Open Dewesoft X software and go in Settings

Operation mode must be set to Real measurement. To add new devices click the plus button, and then add a new device. Under Dewesoft NET select a Measurement unit, and add it as a device.

Image 11: Set the Real measurement operation mode, click on the plus button, and add a Dewesoft NET Measurement unit

Now you will see all available measurement units (names, MAC addresses, ...).

Dewesoft Launcher must run on measurement devices so that they can be seen as available units.

Image 12: Now you can see all the available measurement units

Image 13: You can also type in the other system's IP address in the 'Measurement unit name' and connect to it

## Principle of Dewesoft NET application Module

It is important to note that by default actual data is stored on the measurement units, even though it can be viewed from the clients. This is critical to protect yourself against data loss which might occur by the network going down or transmission being interrupted. Even if this happens, the data is safely stored on the measurement units. When the network connection is reestablished, it is possible to reconnect automatically.

Even if the network going down or transmission was being interrupted, the data is safely stored on the measurement units. The idea of Dewesoft NET technology is to have a distributed system when:

• the required computing power is too high for a single measurement unit (many channels sampled with a high sample rate),
• there is too much distance between the units for analog data transfer,
• the measurement unit is not accessible (dangerous measurements, test rig measurements, ...),
• data from measurement units shall be displayed on several client computers,
• measurements have to be remotely controlled or supervised.

Image 14: Principle of the Dewesoft NET data transfer

Within Dewesoft NET the master client completely controls the slave measurement unit - when the master unit switches to the setup screen, also the slave unit switches to the setup screen.

It is often not possible to transfer all possible channels in real-time to the client for storage, even using a gigabit Ethernet interface.

Imagine even one Dewesoft system with 32 channels, being sampled at 200 kB/s each at 24-bit mode. This is already 25.6 MB/sec, which is more than 200 Mb per second (where each Byte = 8 bits). It does not take long for the network to be completely overloaded with data and be overwhelmed with packet loss.

Immediately after the acquisition is stopped, a button appears on the controlling client allowing the data file(s) to be uploaded from the measurement units for viewing on the client computer.

## How to set up a Master Client?

In the case where your Dewesoft systems are all slave measurement units, you need one master client to control them. Let’s assume that we are now sitting at this computer and have Dewesoft X properly installed and ready. Open the Settings menu.

Now use the selector to assign this computer to be the Master client, as shown below:

Image 15: Set one system as a Master client, which will control the other systems

After confirming the Dewesoft NET setup, the following window will appear:

Image 16: As you exit the Settings with OK, this window will appear where you can connect to the slave measurement unit

Select the Connect button to connect with the measurement unit. After successfully connecting, the measurement unit will be seen as it is shown on the image 16.

You can also change the Channel prefix, and instead of the [Host name] which would in our case be 192.168.10.2, choose for example MU, which stands for a Measuring Unit.

Image 17: After connecting with the measurement unit you will be able to see it under NET tab in a Channel setup

Note that the slave measurement unit called 192.168.10.2 was already found in our example. But if you have not already configured and connected to a measurement unit, just click the Add button and select one or more measurement units in order to add them to the system.

Now click OK to close this dialog and you will notice that the basic Dewesoft X screen has a new addition to the top bar – a NET icon:

Image 18: Click on the NET icon and select Show status

Click on the NET icon to show the connection screen. Clicking the Measure bandwidth button in the system will check network performance. In a 100 Mbit network, the transfer speed is about 10 MB/second while Gigabit LAN offers speeds close to 100 MB/second. Please note that the real bandwidth is also limited by system performance.

Image 19: Click on the NET icon to preview the connection screen, where you can also measure the bandwidth

## How to set up up a Slave Client?

If you want your unit to be set as a slave client, you must first enable remote connections.

Image 20: Enable 'Allow remote connection to this system' on a measurement unit side to set up a slave client

In the example below, the system sees many measurement units on the network, called MU1, MU2, MU3, etc.

Image 21: Many measurement units coupled together

Further setup can be done in Master Client Settings:

• Store data on remote measurement units (checked by default, and highly recommended!)
• Store data on slave clients
• Disable mouse and keyboard on measurement units:
• If you want to prevent a local operator from changing any settings on the measurement unit or interfering with the test. With this checked, the measurement unit cannot be operated locally – you will have complete control over the client.

Image 22: Further settings that can be made on a Master Client's side

## How to Setup the Measurement and start Measuring?

In this section you will learn the procedures to control the acquisition from the client:

• creating a display on the client
• storing data on the measurement unit
• transfer stored data to the client

## Creating a display on client

Before you begin storing, you may want to set up the local display. In previous steps, you may have configured the display of one or more measurement units, but you probably want to see data here, too!

You certainly know how to do this. Go to the Measure mode on the Master client and at the top of your own screen, you have the add Widget button here on the Client to create displays with any combination of channels from any and all measurement units.

As mentioned previously, all measurement units must have a SYNC method in place in order to ensure these three things:

• truly synchronized data files from multiple measurement units
• ability to display channels from more than one measurement unit on the client
• ability to create math channels on the client with channels from more than one measurement unit

Note that the CHANNELS list is now showing channels with the "name" of the MU that they come from automatically. This is so that you know the source of every channel in an easy and convenient way.

Image 23: MU channels are defined for the Measurement Unit, which is in our case the 192.186.10.2 system

In our example, the name of the MU is added in front of the transfer channels.

The channels from each measurement unit will be shown this way automatically. This is the only thing that differs from setting up a screen in the standalone mode of Dewesoft X.

## Storing data on the measurement unit

With the client and the measurement unit properly configured, we can now store data. Just click Store in the toolbar in the normal way.

Image 24: Start storing

## Transfer stored data to the client

As soon as the storing is stopped, an important button appears automatically, called Transfer button:

Image 25: In case you are storing data on the measuring unit, you will be able to see the Transfer button as you will stop storing the measurement

Please click it, and the data file(s) from all measurement units that we just used will be downloaded to the client for you. A "transfer box" appears to show the progress and eventual completion of the download:

In this case, we only had one measurement unit, so only one file needed to be downloaded.

Click the NET menu option to see the list of options:

Image 27: NET options

Notice from the menu that you have several useful capabilities:

 NET options Description Connect/Disconnect from a measurement units Connect to all measurement units/releases the connection Close Dewesoft X on measurement units Closes the Dewesoft X application on all measurement units Measure bandwidth Measuring the bandwidth (transfer speed) between the measurement units and this client Show status Displays window with current status of all measurement units Reboot measurement units Reboots the measurement unit computers (useful if they have crashed or hung up) Shut down measurement units Shuts down the measurement units (requires ACPI power system on the measurement units) Wake up measurement units Starts measurement units (requires 'Wake-up on LAN' option enabled on the measurement units)

## How to Analyze the Transferred data?

Once the captured data files are downloaded to the client, you can replay them there.

Click the Analyse button and locate any transferred files that you have. Notice that we also put the name of the measurement unit into the filename by default, so that you can see that this file came from a measurement unit called MU.

The filename was set to Test. So the name shown here is Test.192.168.10.2.

Image 28: Choose the transferred file, which is in this case named Test.192.168.10.2

Double-click it to open and use the normal tools for analyzing, reviewing, printing, and more.

## USB 2.0 Bandwidth Limitation

One reason why we use NET configurations is that USB bandwidth is limited. USB port has a lower bandwidth limitation than an ethernet port:

• 35 MB/s (in practice ~ 30 MB/s)
• Dewesoft USB limit notice at 26 MB/s
• USB 3.0 does not help upstream

### General formulas for Calculation

 AI and AO channels $$Number Of Channels \cdot Sample Rate \cdot 4 \frac{\cdot Bytes }{Sample }$$(/2 is you use HighSpeed) CNT channels $$NumberOfChannels \cdot SampleRate \cdot 8 \frac{Bytes}{Sample}$$ CAN channels $$NumberOfCANports \cdot \frac{Baudrate}{8}$$ Slave units (only for clock/trigger sync) $$SampleRate \cdot 8 \frac{Bytes}{Sample}$$

It is very important how the USB port is internally wired in the computer - 30 MB/s per single root hub.

Dewesoft calculator is a simple tool that calculates USB transfer (MB/s) for various Dewesoft devices. You can download it here or by clicking on the picture below.

Image 29: Dewesoft Calculator

## NET transfer limitations

The limitations of NET transfer are dependent on:

• the speed of Ethernet link in case of large bandwidth
• the write speed of the hard drive in case of large data storage
• CPU performance in case of advanced math

We are limited with data transfer because all the PCs are connected together with 1Gb LAN cable.

The next table shows the upper limits of transferred data (in samples/second) per 1 PC. Each PC can store approximately 25.600.000 samples per second and that number of samples can be distributed randomly between measurement units.

With full this sample rate, PC stores approximately 100 MB/s of data:

 Time Data size 10s 1GB 1min 40s 10GB 16min 40s 100 GB 2h 46min 40s 1 TB

## How to Synchronize the devices?

The basic idea of synchronization is to provide a clock signal from a  time source. Clock slave receives the signal from the clock provider and the devices are synchronized.

Devices can be synchronized in two different ways:

• Software synchronization - The software synchronization accuracy is around 2-10 ms, which is enough for a simple temperature measurement. This synchronization solution requires no additional hardware.
• Hardware synchronization - This is a hardware solution that can synchronize all USB devices (SIRIUS, DEWE-43, ...) and EtherCAT devices (KRYPTON).

In the example below, we have connected one Sirius, one DEWE-43, and one Krypton measurement unit to the S-BOX.

Image 30: Many devices connected together

## Time sourceImage 31: Selecting the Time source

Time source provides a clock for synchronization. It can be selected from:

• Dewesoft DAQ devices (when we have a Dewesoft measurement device connected to our computer),
• External (Clock/Trigger, IRIG-B DC, NTP, GPS PPS),
• PC clock (when we have only a computer, without a measurement device), or
• GPS devices (Dewesoft RS232 (Topcon/Javad/NVS), NMEA compatible GPS, ...).

Synchronization types are dependent and automatically adjusted from the DAQ devices connected to our system.

## Type of synchronization

If Dewesoft DAQ device is selected as a time source, the clock provider must be selected from:

Image 32: Select the Clock provider for Dewesoft DAQ Devices

 Type of synchronization Description Automatic This option automatically selects the best option for synchronization regarding the hardware connected to the system. Standalone Only one device, there is no synchronization between devices needed. SoftSync This synchronization solution requires no additional hardware. The accuracy is > 10 ms. Clock/Trigger A clock and a trigger signal are used. With each trigger signal, a sample is acquired. IRIG-B DC It contains time-of-year and year information in a BCD format (it contains the information about the absolute time). This is the best way to synchronize the devices because it is the most exact one. GPS PPS Since the satellites are transmitting exact absolute time and better receivers usually output this pulse with a high precision (below one microsecond), we can use this technology to synchronize remote systems - and there is no distance limit. NTP Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems. It is less accurate than other methods.Image 33: Edit NTP clock synchronization To enter the addresses of the NTP server click the edit button near the drop-down menu. If you want to have more devices synchronized via NTP protocol, the same server address must be entered in all of them.Image 34: Enter the addresses of the NTP server When you check NTP servers, the time and date of the server will be displayed. If the server address is wrong, the check will fail.Image 35: As you check NTP servers the time and date of the server will be displayed

## Synchronization between Dewesoft USB devices

 Accuracy When to use Device Clock/trigger ~ 1 us stationary Dewesoft, RoaDyn… IRIG-B DC ~ 1 us stationary Dewesoft, Meinberg,… GPS PPS ~ 1 us mobile GPS receiver NTP + 10 ms ethernet NTP server SoftSync + 10 ms when there is no external time source /

Any Dewesoft device can be precisely synchronized by hardware (Sirius, Dewe-43, Minitaur, DS-CAN2).

## Synchronization Connections

When using the NET system, there are several possibilities that can be used for synchronization:

 Synchronization Types Connection Example Clock/Trigger(relative time) Image 36: Clock/Trigger connection example IRIG-B DC Master(absolute time) Dewesoft device as IRIG-B DC generator:Image 37: Dewesoft IRIG-B DC one unit connection example External IRIG-B DC provider:Image 38: External IRIG-B DC provider connection example GPS PPS(absolute time) Dewesoft device has a GPS receiver:Image 39: GPS PPS one unit connection example External GPS receiver:Image 40: External GPS receiver connection example for GPS PPS synchronization NTP(absolute time) Image 41: NTP sync connection example

## Synchronization with ECAT-SYNC-JUNCTION

ECAT-SYNC-JUNCTION works in the same way as other Dewesoft devices. It is automatically recognized within Dewesoft X software (supported from version X2 SP4). By default, ECAT-SYNC-JUNCTION will be set up to synchronize between KRYPTON EtherCAT® and SIRIUS USB.

With ECAT-SYNC-JUNCTION several connection options are possible:

NOTE - Dewesoft EtherCAT® devices (KRYPTON) are already synchronized between each other by the daisy chain cable, therefore no additional cables are necessary between them.

## How to Remotely control a Measuring Unit?

In this section, we are using only the master client computer to remotely configure and control a measurement unit from this master client. The measurement unit is already connected to it using the steps from the preceding section. All steps are done on the client.

We are not touching the measurement unit at all. It could be a few feet away, on the other side of the building, or miles away. As long as it has a reliable network connection to the client, we can control it from this client!

## Local setup

Now click the Ch. setup button -> NET. In this case, we have used 15 Measuring Units (MU). If you know what the Dewesoft X Setup screen normally looks like, you will notice a subtle but important difference:

Image 47: We have 15 measurement units connected over the Dewesoft NET

Note the tab row of many MU tabs. If you have more than one measurement unit, their names will be shown in this section as tabs. The local computer is our master client, so it does not have any real measurement channels of its own. However, it still has a Math button.

It is interesting to note that you can perform math functions in real-time on this client using any channels that are transferred from the measurement units! You can even combine channels from more than one measurement unit here in math channels – as long as the measurement units are synchronized!

## What does the Transferred Channel mean?

Finally, we will set up the transfer from the measurement unit. What does this mean?

Transfer: "which channels will be sent across the network during recording, for storing and displaying on the client".

That is the entire scope of what transfer means. It has no effect on the storage of all channels on the measurement units (assuming that local storage is enabled! – the default and highly recommended setting). This is important to understand! Therefore, you can have multiple measurement units, each with dozens or even hundreds of channels, and transfer only a few channels – or even no channels – to the client.

Transferring channels will only mean that you will be able to preview and store those transferred channels in real-time on the Master Client. The others - not transferred channels - you will be able to transfer later as the complete data file will be recorded for each measurement unit when the measurement will be done. This is described in the section How to Setup the Measurement and start Measuring? under Transfer stored data to the client.

Due to bandwidth limitations of any network, we recommend being prudent about transferring channels – keep the bandwidth in mind and select only those channels that you really need to see on the client in order to monitor and control the test.

On image 48 you can see that on the MU1 we have selected both two channels, so they will be transferred in real-time to the client. Of course, they will also be stored on the local measurement unit, because this has been selected by default on the hardware setup screen, NET page.

Image 48:  Besides storing data on the measurement unit 1 - MU1, the channels will be transferred in real-time to the client

## How to setup the Channels on the Measurement Unit?

Besides the NET tab, you have also all the available tabs that are consistent with your measurement units. In case your measurement units have analog inputs, CAN inputs, Digital inputs, etc. you will be able to set them up inside those tabs on a Master Client side. Just simply click on one tab and set up the channels according to your needs.

In our example on image 49, we have 15 measurement units, that have only analog inputs, so there is only the 'Analog in' tab available. In the 'Analog in' tab, we are now able to see all analog channels from all measurement units.

Setting up the channels is basically the same as if you would have a standalone unit. You can activate channels with the Used / Unused buttons, scale them using the Setup buttons, and so on. You can also set the dynamic and reduced sample rates, choose a filename, and more. In this example, our Master Client is a computer with more than 200 analog input channels.

In addition, the Math channels can also be created, where you can use any channel from any measurement unit.

Image 49: In Analog in tab, we can preview all analog channels from all measurement units connected over the Dewesoft NET

## Display setup on the measurement unit

This is only important if you want to have a display screen on the measurement unit for local observers to see. If there is no one looking at the local display on the measurement unit (perhaps it is in a remote location without any people near it), then you can skip this step.

But if you want a local display on the measurement unit, you can do this is two ways:

• locally on the measurement unit, or
• remotely over the Master client.

## Setting up a display Locally on a Measurement Unit

Open Dewesoft X locally on a Measurement Unit, and go to the Measure tab. Then set up the screen as you desire, using the normal Dewesoft X methods and conventions for screen design. The measurement will run without being stored in this way, so you can freely set up the measurement displays.

As you will switch to a measure mode over the Master client, this display will be then previewed locally on the Measurement Unit.

NOTE: If you want to set up the display locally on the measurement unit, you have to have disabled option 'Disable mouse and keyboard on measurement units'. Otherwise, you will not be able to switch between tabs, or click anything on the measurement unit.

Image 50: If you want to locally setup the measurement unit's display, disable this option

## Setting up a display Remotely over the Master Client

You can also set up a display for a Measurement Unit remotely over the Master Client. First set up the remote connection in settings:

If you go to the Channel setup -> NET on a Master Client you have 3 screen views to choose between:

• Channel list
• Remote channel setup
• Remote display setup

With switching between those you can remotely connect to any of the Measurement units and set up the channels or displays like this.

Image 50: Setup the measuring screen in a Measure tab of the Dewesoft X

It is really important that the client computer has a display that has more resolution than the measurement units! If your measurement units have 1024x768 screens, your client should have the next size up or greater, else you may run into trouble seeing some of the screen objects near the bottom when remotely controlling measurement units from the client.

The display on image 50 is the one that will appear on the screen of the remote measurement units! It is not the display that you will see here on the client.

## Local NET setup

When the connection was successful, the NET button turns green and the Setup screen appears. Now click the Setup button. If you know what the Dewesoft X Setup screen normally looks like, you will notice a small but important difference.

Local setup screen with buttons to the remote setup screens:

Each system setup (local and remote units) can now be accessed via the button bar (yellow indicates the selected unit).

Note the buttons for Local and Testing-PC. If you have more than one measurement unit, their names will be shown on this bar as well. The Local computer is our master client, so it does not have any channels of its own.

## Math tab

However, the Local computer still has a Math tab. It is interesting to note that you can perform math functions in real time on this client using any channels that are transferred from the measurement units! You can even combine channels from more than one measurement unit here in math channels – as long as the measurement units are synchronized!

Note the buttons for Local and Testrig. If you have more than one measurement unit, their names will be shown on this bar as well. The local computer is our master client, so it does not have any real measurement channels of its own.

## Example of large NET system configuration

An example of a large system connected with the NET system.

Channels:

• Analog, 19 Sirius slices
• XSENS
• GPS
• ARINC