NL121 Ethernet Interface
Add Ethernet Connectivity
Connect a CR1000 or CR3000 to an IP network
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The NL121 is the easiest and lowest-cost way to add an Ethernet interface connection to a CR1000 or CR3000. This small device, about the size of a deck of cards, simply plugs onto the datalogger’s peripheral port. Through the NL121, the Internet capabilities of the datalogger can be accessed, such as PakBus, Modbus, and DNP3 over TCP, as well as Web, email, file transfer, and cloud-based application clients. Using any standard IP network─within an office or across the Internet─data can be collected from the datalogger, and the datalogger can be controlled. 

Benefits and Features

  • The easiest way to add Ethernet to a CR1000 or CR3000
  • Provides a native Ethernet connection, allowing the datalogger to communicate directly using a variety of Internet protocols
  • Integrated protection for surge and ESD
  • Datalogger-controlled power-management schemes for low-power operation


NL121 front view
NL121 back view
NL121 left view
NL121 right view
NL121 top view
NL121 bottom view
NL121 with CR1000


Datalogger Interface 40-pin peripheral port on CR1000 or CR3000
Ethernet 10/100 Mbps, auto-detect 10BaseT/100Base-TX, full/half duplex, IEEE 802.3, auto MDI/MDI-X
Power Source 12 V from datalogger 40-pin peripheral port
Power Consumption 55 mA typical
Operating Temperature Range -40° to +70°C
Dimensions 10.2 x 6.4 x 2.8 cm (4.0 x 2.5 x 1.1 in.)
Weight 66.62 g (2.35 oz)


Application of Council Directive(s) 2004/108/EC Electromagnetic Compatibility Directive (EMC)
Product Standard EN 61326-1:2013 – Electrical Equipment for measurement, control and laboratory use (EMC requirements – for use in industrial locations)
2011/65/EU The Restriction of Hazardous Substances Directive (RoHS2)


Datalogger Requirements

A CR1000 or CR3000 datalogger using operating system version 28 or greater is required.


Frequently Asked Questions

Number of FAQs related to NL121: 6

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  1. The NL121 can be used to add an Ethernet connection to a datalogger.

  2. Compared to a third-party interface, the NL121 is easier to attach, easier to use, performs better, provides access to the IP services and clients in the datalogger OS, and is easier to control through CRBasic commands and datalogger settings due to its integrated nature.

  3. The NL121 plugs into the datalogger and doesn't require an additional cable to work. The NL121 also doesn't take up much extra space. Because the NL121 has a faster interface to the datalogger than the NL201 does, the NL121 communicates faster.

    The NL201 has to be mounted next to the datalogger and requires a cable to connect to it. Also, the NL201 requires some additional configuration so that it will work with the datalogger. For example, choices have to be made regarding how the NL201 is connected to the datalogger. 

  4. By adding an Ethernet connection to a datalogger, a user can communicate with the datalogger over an Internet connection. This allows a user to administer the datalogger remotely over a company network or from across the Internet. A user can collect data, reconfigure, and update a datalogger without having to be onsite. 

  5. The NL116 is the same as the NL121, with the addition of a CompactFlash card slot that can be used with a removable CompactFlash card to extend data storage and data collection.

  6. The maximum recommended segment length (length of cable between the NL device and the Ethernet repeater, hub, switch, or router it is connected to) for 10Base-T and 100Base-Tx networks using CAT5e cable is 100 m. 

Case Studies

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