Meilhaus Electronic RedLab WebDAQ 316 User manual

RedLab WebDAQ 316 User's Guide
September 2019. Rev 5
Contents
About this User's Guide
Introducing the RedLab WebDAQ 316
Seng up the WebDAQ
Funconal Details
Specificaons

About this User's Guide
This user's guide describes the Meilhaus Electronic RedLab WebDAQ 316 data acquision device, the WebDAQ
web interface, and lists device specificaons.
Where to find more informaon
Addional informaon about the WebDAQ Series of internet enabled data loggers is available on our website at
www.meilhaus.de/en. You can also contact Meilhaus Electronic with specific quesons.
WebDAQ web interface: Open the Help window for informaon about using WebDAQ soware.
Email: [email protected]
Phone: [phone] and follow the instrucons for reaching Tech Support
Hazardous voltages
Take the following precauons if you connect hazardous voltages to the RedLab WebDAQ 316 spring terminals.
A hazardous voltage is a voltage greater than 42.4 Vpk or 60 VDC to earth ground.
Ensure that hazardous voltage wiring is performed only by qualified personnel adhering to local electrical
standards.
Do not mix hazardous voltage circuits and human-accessible circuits on the same device.
Make sure that devices and circuits connected to the RedLab WebDAQ 316 are properly insulated from
human contact.
When device terminals are hazardous voltage LIVE (>42.4Vpk/60 VDC), you must install the high voltage screw
terminal backshell (ACC-401) to ensure that the terminals are not accessible and that the devices and circuits
connected to the RedLab WebDAQ 316 are properly insulated from human contact.
Hazardous locaons : The RedLab WebDAQ 316 is not cerfied for use in hazardous locaons.
Contents
RedLab WebDAQ 316 User's Guide
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Introducing the RedLab WebDAQ 316
The RedLab WebDAQ 316 is part of the WebDAQ Series of Internet enabled data loggers. RedLab WebDAQ 316
is a thermocouple acquision and logging device that provides the following features:
16 differenal thermocouple inputs
75 S/s sample rate (all channels)
250 Vrms channel-to-earth isolaon
Overvoltage protecon between any two inputs
50/60 Hz noise rejecon
Cold juncon compensaon (CJC)
Auto zero channel
Four bidireconal, isolated DIO that are individually configurable for input (trigger) or output (alarm)
10/100 Ethernet interface
Support for USB WiFi adapters for wireless connecvity
Support for USB mass storage devices and SD cards for data logging or file transfer
Powered by an external power supply (included)
WebDAQ Series devices are designed with an integrated operang system and web interface. You communicate
with the device over a network connecon using the web interface opened in a web browser.
Mobile support – access the WebDAQ from any device with a web browser, such as a phone or tablet
Remote monitoring and control
Run simple to complex logging operaons
Flexible task scheduling
Powered by Raspberry Pi
The WebDAQ is designed with the Raspberry Pi Compute Module, featuring a quad core processor with speeds
up to 1.2 GHz, 1GB RAM and 4 GB Flash memory.
Integrated operang system and web service
The WebDAQ is a complete data acquision system containing an embedded operang system and web server.
The operang system resides in internal flash memory, and includes a web service and device driver. All
configuraon, acquision, and data management is performed using the web interface.
Ethernet interface
The WebDAQ has a built-in 10/100 BASE-T auto-negoaon, high-speed communicaon port. You can access
and configure your WebDAQ from anywhere with access to the network to which it is connected. A unique
MAC address is assigned to each device at the factory. You configure the Ethernet connecon sengs through a
web interface. The default network name uses the format webdaq-xxxxxx, where xxxxxx are the lower six digits
of the factory-assigned MAC address. You can change this name with the web interface.
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Open-source soware
WebDAQ firmware uses open-source soware components. Refer to Licenses for the licensing informaon of
each component. Open-source code is available upon request from [email protected].
Funconal block diagram
Device funcons are illustrated in the block diagram shown here.
Figure 1. Funconal block diagram
Unpacking
As with any electronic device, you should take care while handling to avoid damage from stac
electricity. Before removing the board from its packaging, ground yourself using a wrist strap or by simply
touching the computer chassis or other grounded object to eliminate any stored stac charge.
Contents
RedLab WebDAQ 316 User's Guide
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Seng up the WebDAQ
Connecng to a local area network
The WebDAQ requires a TCP/IP connecon to a network or the Ethernet port of a computer. A standard
Ethernet cable is shipped with the device. The WebDAQ IP address type is set by default for DHCP/Link-Local.
When connected to a network, the device first aempts to receive an IP address from a DHCP server. If this
fails, a link-local address is used. Use of a stac address requires configuraon via the web interface. The IP
address idenfies the WebDAQ on the network, and is used to access the web interface.
Connecng to a network with DHCP enabled
Connect one end of the Ethernet cable to the connector on the WebDAQ rear panel, and connect the other end
to a 10Base-T or 100Base-TX compable Ethernet port, hub, or switch.
Once the device is detected, DHCP assigns an address. A different address may be assigned each me the
hardware is connected to the network.
WiFi support
Aer successfully configuring a wired connecon, you can use the web interface to configure the
WebDAQ for wireless communicaon. Refer to the Configuring the WebDAQ for wireless
communicaon secon for more informaon.
Connecng directly to a PC
Connect one end of the Ethernet cable to the connector on the WebDAQ rear panel, and connect the other end
directly to the Ethernet port on a PC. The WebDAQ aempts to communicate with the host PC using
169.254.100.100 – the link-local address stored on the device. The host PC may accept this address or use a
different address. The link-local address is valid only for communicaons between the WebDAQ and the host PC
to which it is connected.
Connecng the external power adapter
Connect the network cable before connecng to external power
Connecng to the external supply before installing on a network results in the device aempng to
auto-negoate a network address before one is available.
An external power adapter is included with each shipment (PS 9V1AEPS230V).
Connect the adapter to the power connector labeled EXT PWR on the device rear panel, and plug the AC
adapter into an electrical outlet.
Press the POWER buon. The POWER LED on the rear panel turns yellow as the hardware starts up, and green
when it is ready for use.
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Detecng the device on a network
WebDAQ uses the "zeroconf" zero-configuraon protocol to announce its presence on a local area network.
Zeroconf uses a device name which can be accessed from other computers on the network.
Zero-configuraon networking is helpful to find your WebDAQ hardware on the network
The easiest way to add zeroconf support to Windows is to install Bonjour Print Services. Bonjour
soware is Apple's implementaon of zero-configuraon networking, and is readily available as a free
download – open a browser window and search for Bonjour Print Services. Zeroconf is built into popular
applicaons such as Apple ITunes® and instant messaging soware, so your computer may already
support it. Many Linux systems will have the avahi version of zeroconf installed by default, so it's likely
zeroconf is available if you're running Linux.
Accessing the WebDAQ web interface
To access the WebDAQ web interface, open a browser window and enter hp://webdaq-xxxxxx.local, where
xxxxxx is the last 6 digits of the MAC address. The MAC address is on a label at the boom of the WebDAQ
enclosure.
If your network is configured for the zeroconf protocol, the WebDAQ web interface opens.
If the web interface does not open or an error is returned, install a device discovery tool such as Bonjour
Print Services. Refer to the note above about zero-configuraon networking.
The WebDAQ web interface is shown here.
Figure 2. WebDAQ web interface
Use the WebDAQ web interface to configure hardware and acquision opons, schedule and run jobs, and to
view and manage data. The Help window provides details about all components on the web interface.
Once a connecon is established and you can communicate to the device, you can change the configuraon for
other network scenarios.
* The latest version of Chrome, Firefox, Safari, UC Browser, or Opera recommended. Compable with IE v11
with the latest Windows Updates installed. Not recommended for use with other IE versions or the Edge
browser.
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Configuring the WebDAQ for wireless communicaon
Once communicaon is established on a wired network, you can connect a WiFi adapter to the USB port and
use the web interface to configure the WebDAQ for communicaon over a wireless network. With the WebDAQ
connected through the wired connecon, perform the following procedure.
1. Connect an approved WiFi adapter to the USB port on the WebDAQ rear panel.
2. Open the WebDAQ web interface in a browser window and go to the Device window, Network tab.
3. Select WiFi. Once the list of available networks updates, select the wireless network that you want to
connect to, and enter the password, if any.
If the connecon is successful, the selected wireless network will show above this list with a checkmark
next to it.
You can click on the selected network to open a WiFi Network Sengs dialog box where you can forget the
current network or configure the IP address type (DHCP/Link-Local or Stac).
4. Disconnect the Ethernet cable from the LAN connecon.
Wait a few seconds, and refresh the browser window.
Changing to a wireless network may require a reboot
If a connecon can't be established aer changing the network, you may need to reboot the operang
system and restart the WebDAQ using the Power buon.
Configuring the network router for communicaon across networks
To communicate with the WebDAQ over the internet from a computer connected to a different network, you
must change the network configuraon of the network router.
Cauon! This procedure should only be performed by a network administrator or computer
professional. Incorrect sengs can significantly disrupt a network.
In the following procedure, the WebDAQ is installed on the host LAN, the computer is installed on the client
LAN, and it is assumed that you have successfully connected the device to a local network.
1. Determine the IP address of the WebDAQ – open the Device window from the web interface, and note the
IP Address value on the Network Sengs tab.
2. Configure your router so that the address determined above is a stac address. The procedure for
accomplishing this varies between routers; refer to your router documentaon for instrucons.
3. Configure the firewall/router to forward an unused port to port 80 on the WebDAQ at the IP address
configured for the device.
Note the stac IP address assigned to the router – this is referred to as the WAN address.
4. To access your WebDAQ from a remote locaon, enter the WAN address followed by the port selected
above preceded by a colon in the web browser.
The format of the address entered in the browser is: 00.000.00.00:00000 (WAN address of router:port
selected for the WebDAQ).
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Security
Use the web interface to set the level of access to the website and to change the administrator password.
High: access to the web page requires a password.
Medium: access to the web page is permied for any user, and data can be read by any user, but changes
to the device configuraon or files require a password.
Off: full access is permied for all users; no password is required.
By default, security access is set to "Off", and the administrator password is set to "admin".
To change the security level or password, open the web interface and go to the Device window, Security tab.
Use the device Reset buon to restore security sengs to factory default values.
Restoring factory default sengs
To restore network configuraon and security sengs to the factory default values, use a paper clip to press
the CONFIG RESET buon. When pressed, the default network and security sengs are wrien to the device
and the WebDAQ is rebooted.
Factory default sengs
Parameter Specificaon
IP address 192.168.0.101
subnet mask 255.255.255.0
Gateway 192.168.0.1
DHCP seng DHCP + link-local enabled
Security level Off
Password for the admin
account
admin (case-sensive)
Password for the share
account
share (case-sensive)
Device name webdaq-xxxxxx, where xxxxxx is the last 6 digits of the MAC address
(printed on the label on the underside of the device).
The network sengs, security level, user account passwords and device name can be changed with the
WebDAQ web interface.
When factory defaults are restored, any shared folders or mapped drives are reset.
Contents
RedLab WebDAQ 316 User's Guide
page 8

Funconal Details
Front panel components
Figure 3. Front panel
1 Screw terminal 2 Spring terminal
Screw terminal
Connect up to four digital I/O lines (DIO0 to DI03) to the detachable screw terminal.
Figure 4. Screw terminal pinout
The digital ground (GND) terminals provide a common ground for the digital bits.
Digital connecons
The digital I/O lines are electrically isolated from the thermocouple circuits. Each bit is individually configurable
for input (trigger) or output (alarm), and features Schmi trigger inputs and open drain outputs. All DIO
channels are pulled high to 5 V.
Any digital bit can be configured with the web interface as a trigger to start or stop an acquision. Any digital
bit can also be configured to trigger an alarm, and be driven high or low when an alarm occurs.
Spring terminal
Connect up to 16 thermocouples (TC0+/TC0– to TC15+/TC15–) and two common reference connecons (COM)
to the 36-posion detachable spring terminal. Refer to Figure 5 for signal locaons.
Cauon! We strongly recommend that you ground yourself using a wrist strap before handling
thermocouple sensors.
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Figure 5. Spring terminal pinout
Thermocouple connecons
A thermocouple consists of two dissimilar metals that are joined together at one end. When the juncon of the
metals is heated or cooled, a voltage is produced that correlates to temperature.
The RedLab WebDAQ 316 supports type J, K, S, R, B, E, T, N thermocouples (TC), and provides overvoltage
protecon between any two inputs. A typical thermocouple connecon is shown in Figure 6.
Figure 6. Typical thermocouple connecon
Connect the shield to a common mode voltage reference on the thermocouple. A valid reference is voltage
within ±1.2 V of all the connected thermocouples.
Minimizing thermal gradients
Changes in the ambient air temperature near the thermocouple connectors or a thermocouple wire conducng
heat directly to terminal juncons can cause thermal gradients. Observe the following guidelines to minimize
thermal gradients and improve system accuracy:
Use small-gauge thermocouple wire. Smaller wire transfers less heat to or from the terminal juncon.
Run thermocouple wiring together near the spring terminal connector to maintain a consistent
temperature.
Avoid running thermocouple wires near hot or cold objects.
Minimize adjacent heat sources and air flow across the terminals.
Keep the ambient temperature as stable as possible.
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Increasing the thermocouple length
If you need to increase the length of your thermocouple, use the same type of TC wires to minimize the
error introduced by thermal EMFs.
Rear panel components
Figure 7. Rear panel
1 External power
connector
4 LED indicators (4) 7 Ethernet connector
2 Power buon 5 SD card slot 8 Ground connector
3 Funcon buon 6 Factory reset buon
(recessed)
9 USB connectors (2)
External power connector
Connect the external AC adapter that shipped with the device to the connector labeled EXT PWR on the rear
panel. Click here to jump to the power specificaons.
If using a different power supply than what was shipped with the hardware, ensure that the supply has a
posive center pin.
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Power buon
The buon labeled POWER turns the WebDAQ device on and off. WebDAQ hardware is designed with a 2-pin
jumper (W1) that users can remove to connuously power the device. The behavior of the POWER buon
when jumper W1 is installed or removed is listed in the following table.
Jumper W1 installed
(factory default seng)
Jumper W1 removed
When the device is off, press the POWER buon
briefly to turn the device on.
The device is always on as long as the power
adapter is connected and receiving power
(Power-On Mode).
When the device is on, press the POWER buon
for approximately 1 second to shut down the
operang system and WebDAQ hardware;
release the buon when the POWER LED blinks
yellow.
The operang system automacally powers off
the device at the end of the shutdown
procedure.
Press and hold the POWER buon for
approximately 4 seconds to force the device to
power off. Any unsaved changes may be lost
when powering down using this method.
Press for approximately 1 second to reboot the
device; release the buon when the POWER LED
blinks yellow.
Refer to Power-On Mode for the procedure to remove jumper W1 and enable Power-On mode.
The WebDAQ device can also be restarted or shut down using the web interface; refer to the WebDAQ
help for details.
Funcon buon
The buon labeled FUNC has two funcons; it can be used to eject external media or to start/stop an
acquision.
Eject external media (default): Pressing the buon unmounts all removable media so they can be safely
removed from the device.
Start or stop an acquision (requires configuraon with the web interface): When configured, pressing
this buon starts an acquision, or stops an acquision that is currently running.
Use the web interface to safely unmount removable media, when present.
When removable media is plugged into the WebDAQ, the operang system opens it for wring. To safely
remove the media, you must unmount it first.
When a job is configured to log data to external media, pressing FUNC while the job is running will not eject the
media.
The MEDIA LED is steady green when all media is unmounted and safe to remove, and off when all media is
removed.
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LED status indicators
The WebDAQ has four LEDs on the rear panel that indicate the status of power and host communicaons. The
following table defines the LED states during normal operaon.
LED states – normal operang mode
Label State Descripon
1: POWER Steady yellow Device is boong up
Steady green Device boot is successful.
Blinking yellow Device is shung down.
Off Device is off.
2: STATUS Blinking yellow Device is configuring hardware.
Steady green Hardware configuraon is complete.
Flashing green
100 ms on/2s off)
Waing for a scheduled start condion to be met.
Blinking heartbeat Scheduled start condion is met; waing for job start
condion to be met.
Blinking green Data is being acquired (job start condion is met).
Off No error detected.
3: ERROR Blinking yellow Error condion is detected. This LED blinks even when the
soware is configured to ignore the error.
Error state is cleared when the next schedule starts.
Off No error detected.
4: MEDIA Blinking yellow A job is configured to log to external media, but the job
hasn't started yet; pushbuon will not let you eject media.
Steady yellow External media is inserted into the SD card slot or USB
storage port.
Blinking green Currently logging to an external SD card or USB storage
device.
Steady green Media has been made safe for removal using the funcon
buon, but has not been removed.
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WebDAQ LEDs behave differently when soware is updated on the device. The following table defines the LED
states during a soware update.
LED states – soware update mode
LED State Descripon
All LEDs Solid yellow Soware update is starng
POWER Blinking yellow Soware update is running
STATUS Blinking green Update file is located; device is being updated
Blinking yellow Update file cannot be located; insert media with update
file
ERROR Blinking green Update is successful; device will reboot in approximately
5 seconds
Blinking yellow Update failed; user must retry
Refer to Updang WebDAQ firmware for more informaon about WebDAQ firmware.
SD card slot
The SD slot accepts SD (Secure Digital), SDHC, SDXC, MMC, and TransFlash memory cards. Memory cards can be
ejected using the web interface or the hardware FUNC buon, unless the buon is configured to start/stop an
acquision.
When removable media is plugged into the WebDAQ, the operang system opens it for wring. Use the FUNC
buon or web interface to unmount the SD card before removing.
Acquiring data at high speeds can generate large file sizes
If you expect to acquire a large amount of data to a single file when logging to external media, do not
use media formaed with the FAT32 file system. FAT32 is limited to a 4 GB maximum file size. If the log
file on FAT32 media grows beyond that size, a "File too large" error is returned and the acquision stops.
Before starng a logging session of this type, reformat the media using a different file system such as
NTFS. Refer to the Frequently Asked Quesons help topic for more informaon about file systems.
Factory reset buon
The recessed buon labeled CONFIG RESET restores network and alarm sengs to factory default values.
When pressed, the default sengs are wrien to the device and the WebDAQ is rebooted. Refer to the
Restoring factory default sengs secon for a list of the default sengs that are restored.
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Ethernet connector
The WebDAQ has one 10 Base-T/100 Base-TX, auto-negoaon, high-speed communicaon port. The port
connector is an RJ-45, eight-posion connector. The Ethernet port accepts shielded or unshielded twisted pair
cable. The maximum communicaon distance without using a repeater is 100 m (328 ).
Ground connector
The WebDAQ ships with a ground screw in the connector labeled #6-32. To ground the WebDAQ chassis, aach
a ring lug to a 14 AWG (1.6 mm) wire. Connect the ring lug to the grounding screw on the WebDAQ rear panel.
Aach the other end to a safety ground.
USB connectors
The two high-speed USB ports can be used for connecons to a mass storage device and approved WiFi
adapter.
When removable media is plugged into the WebDAQ, the operang system opens it for wring. Use the FUNC
buon or web interface to unmount the USB device before removing.
Use a self-powered hub when external media requires higher current
USB-powered hard drives may use an excessive amount of current during operaon. The WebDAQ
device could shut down or experience other errors if the power requirements of a connected device
exceed the power available. Use a self-powered hub if the current requirement of external media
exceeds 500 mA.
We recommend that you connect USB-powered hard drives before powering up the WebDAQ.
Acquiring data at high speeds can generate large file sizes
If you expect to acquire a large amount of data to a single file when logging to external media, do not
use media formaed with the FAT32 file system. FAT32 is limited to a 4 GB maximum file size. If the log
file on FAT32 media grows beyond that size, a "File too large" error is returned and the acquision stops.
Before starng a logging session of this type, reformat the media using a different file system such as
NTFS. Refer to the Frequently Asked Quesons help topic for more informaon about file systems.
Analog input circuitry
Each channel passes through a differenal filter and then is mulplexed and sampled by a 24-bit ADC. The
channels share a common ground (COM) that is isolated from the digital subsystem.
The circuitry for one thermocouple channel is shown in here.
Figure 8. Input circuitry of one TC channel
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Open thermocouple detecon
Each channel has an open thermocouple detecon (OTD) circuit which consists of a current source between the
TC+ and TC– terminals. If an open thermocouple is connected to the channel, the current source forces a full-
scale negave voltage across the terminals.
Input Impedance
Each channel has a resistor that produces an input impedance between the TC and COM terminals. The gain
and offset errors resulng from the source impedance of connected thermocouples are negligible for most
applicaons. Thermocouples with a longer lead length can introduce more significant errors.
Overvoltage protecon
WebDAQ provides 30 V overvoltage protecon between any two inputs.
Thermocouple measurement accuracy
Thermocouple measurement errors depend partly on the type and accuracy of the thermocouple, the
temperature being measured, the resistance of the thermocouple wires, and the cold-juncon temperature.
For increased accuracy, follow the guidelines in the Minimizing thermal gradients secon, and use the auto zero
channel to compensate for offset errors.
Cold-juncon accuracy
Heat dissipated by nearby heat sources can cause errors in thermocouple measurements by heang the RedLab
WebDAQ 316 terminals to a different temperature than the cold-juncon compensaon sensor. Thermal
gradient across the terminals can cause the terminals of different thermocouple channels to be at different
temperatures, which creates accuracy errors and affects the relave accuracy between channels.
The temperature measurement accuracy specificaons include errors caused by the thermal gradient across
the RedLab WebDAQ 316 terminals for configuraons with the terminals facing forward or upward.
Auto zero channel
The RedLab WebDAQ 316 has an internal auto zero channel to compensate for offset errors. When enabled, the
WebDAQ measures the autozero channel and subtracts that measurement from the measurement of each
thermocouple channel. Use the web interface to enable auto zero. RedLab WebDAQ 316 specificaons assume
that auto zero is enabled and applied to every sample.
Power-On Mode
WebDAQ Series hardware can be configured to start automacally when power is applied, instead of requiring
users to press the POWER buon. This is useful if the WebDAQ is operang in a remote locaon and a power
loss occurs. This "power-on mode" is enabled by removing a 2-pin jumper (labeled W1) from the WebDAQ
circuit board.
When jumper W1 is removed, the device does not shutdown completely unless the power adapter is
unplugged from the device or power source.
Perform the procedure below to remove jumper W1 from the WebDAQ circuit board and enable power-on
mode.
Cauon! The discharge of stac electricity can damage some electronic components. Before removing
the WebDAQ device from its housing, ground yourself using a wrist strap or touch the computer chassis
or other grounded object to eliminate any stored stac charge.
1. Power down the WebDAQ device and disconnect the power supply.
2. On the rear panel, remove the Ethernet cable, power cable, SD card, and any USB devices.
3. Remove the #6-32 ground screw.
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4. Remove the nut and washer from the EXT PWR connector.
5. Remove the two front panel bezel screws and remove the front bezel.
6. Slide out the circuit board with the front panel intact.
7. Remove jumper W1 from the specified locaon shown below.
8. Slide the circuit board back into the enclosure.
9. Aach the front bezel and secure with the two bezel screws removed in step 5.
10. Secure the power connector with the nut and washer (removed in step 4) to the power connector, and
aach the ground screw, Ethernet and power cables, and any USB devices.
To automacally run a schedule when the WebDAQ powers up, enable the "Automacally start schedule on
system startup" opon on the Schedule Sengs dialog box of the web interface. If a power cycle occurs, the
schedule will restart from the beginning, regardless of which job was running when the power was lost. In
order to retain the data from each schedule start, make sure to set the logging opon for each job to "Append
Date/Time to File Name" so that each run aer power loss creates a new data file rather than overwring the
original file. Refer to the WebDAQ help for details about how to configure schedule and logging opons.
Enabling power-on mode with a complex or date/me triggered schedule
When running a complex or date/me-triggered schedule with both power-on mode and auto start
schedule enabled, be aware that the schedule may not run automacally aer a power cycle if the date
or me trigger is no longer valid. In this case, the user may sll access the WebDAQ remotely to modify
the start sengs.
Replacing the baery
A buon cell lithium baery provides the me reference for WebDAQ hardware when the device is powered
off. The average lifespan of the baery is approximately 10 years.
Cauon! The discharge of stac electricity can damage some electronic components. Before removing
the WebDAQ from its housing, ground yourself using a wrist strap or touch the computer chassis or
other grounded object to eliminate any stored stac charge.
Perform the following procedure to replace the baery.
1. Power down the WebDAQ device and disconnect the power supply.
2. On the rear panel, remove the Ethernet cable, power cable, SD card, and any USB devices.
3. Remove the #6-32 ground screw.
RedLab WebDAQ 316 User's Guide
page 17

4. Remove the nut and washer from the EXT PWR connector.
5. Remove the two front panel bezel screws and remove the front bezel.
6. Slide out the circuit board with the front panel intact.
7. Remove the baery by sliding it forward toward the slot, and replace with a 3 V buon cell baery – type
BR1225, CR1225 or similar.
8. Slide the circuit board back into the enclosure.
9. Aach the front bezel and secure with the two bezel screws removed in step 5.
10. Secure the power connector with the nut and washer removed in step 4, to the power connector, aach the
ground screw, Ethernet and power cables, and any USB devices.
Set the device system clock from the Device window, Device Info tab on the web interface.
Updang WebDAQ firmware
Device firmware is bundled with the operang system, web server, and documentaon in a soware update
(*.swu) file. Firmware updates are posted on the Meilhaus Electronic Firmware Updates page and are available
for download.
Use the web interface to install the *.swu update file. Open a browser window and enter hp://webdaq-
xxxxxx.local/Help, where xxxxxx is the last 6 digits of the MAC address – see the label on the boom of the
enclosure. Refer to the "Updang WebDAQ Firmware" help topic or FAQ for instrucons.
Calibrang the hardware
The Meilhaus Electronic Manufacturing Test department performs the inial factory calibraon. Return the
device to Meilhaus Electronic when calibraon is required. The recommended calibraon interval is one year.
Contents
RedLab WebDAQ 316 User's Guide
page 18

Specificaons
Thermocouple input
Table 1. Thermocouple input specificaons
Parameter Condion Specificaon
Number of
channels
16 thermocouple channels
1 internal auto zero channel
1 internal cold-juncon compensaon channel
ADC resoluon 24 bits
Type of ADC Delta-Sigma
Sampling mode Scanned
Voltage
measurement
range
±78.125 mV
Temperature
measurement
ranges
Works over temperature ranges defined by NIST
(J, K, T, E, N, B, R, S thermocouple types)
Timing mode Automacally set
for either high-
resoluon or high-
speed mode based
on the requested
scan rate,
regardless of the
number of
channels.
High resoluon: requested scan rate is ≤1 Hz
High-speed: requested scan rate is >1 Hz
Timing mode High-resoluon Conversion Time (per channel): 55 ms
Sample Rate (all channels): 1 S/s
High-speed Conversion Time (per channel): 740 µs
Sample Rate (all channels): 75 S/s
Common-mode
voltage range
Channel-to-COM: ±1.2 V min
COM-to-earth ground: ±250 V
Common-mode
rejecon rao
(CMMR)
High-resoluon
mode at DC
and 50 to 60 Hz
Channel-to-COM: 100 dB
COM-to-earth ground: >170 dB
High-speed mode
at 0 to 60 Hz
Channel-to-COM: 70 dB
COM-to-earth ground: >150 dB
Input bandwidth High-resoluon
mode
14.4 Hz
High-speed mode 78 Hz
High-resoluon
noise rejecon
50 Hz and 60 Hz 60 dB
Overvoltage
protecon
±30 V between any two inputs
Differenal input
impedance
78 MΩ
Input current 50 nA
RedLab WebDAQ 316 User's Guide
page 19

Input noise High-resoluon
mode
200 nVrms
High-speed mode 7 µVrms
Gain error High-resoluon
mode
0.03% typ at 25 °C
0.07% typ at 0 °C to 60 °C
0.15% max at 0 °C to 60 °C
High-speed mode 0.04% typ at 25 °C
0.08% typ at 0 °C to 60 °C
0.16% max at 0 °C to 60 °C
Offset error High-resoluon
mode
4 µV typ, 6 µV max
High-speed mode 14 µV typ, 17 µV max
Offset error from
source impedance
0 °C to 60 °C Add 0.05 µV per Ω, when source impedance >50 Ω
Cold-juncon
compensaon
accuracy
0.8 °C typ, 1.7 °C max
Warm-up me The device is lying
flat or facing
upward, with a
constant ambient
temperature.
15 minutes recommended
Temperature measurement accuracy
Measurement sensivity represents the smallest change in temperature that a sensor can detect. It is a
funcon of noise. The values assume the full measurement range of the standard thermocouple sensor per
ASTM E230–87.
Table 2. Temperature accuracy specificaons
Parameter Condion Specificaon
Measurement
sensivity
High-resoluon
mode
Type J, K, T, E, N: <0.02 °C
Type B, R, S: <0.15 °C
High-speed mode Type J, K, T, E: <0.25 °C
Type N: <0.35 °C
Type B: <1.2 °C
Type R, S: <2.8 °C
The following figures show the errors for each thermocouple type when connected to the RedLab WebDAQ 316
with auto zeroing performed. The figures display the maximum error over a full temperature range, and the
typical error at room temperature. The figures account for gain errors, offset errors, differenal and integral
nonlinearity, quanzaon errors, noise errors, 50 Ω lead wire resistance, and cold-juncon compensaon
errors. The figures do not account for the accuracy of the thermocouple itself.
RedLab WebDAQ 316 User's Guide
page 20