Establishing maintenance connection - CL61

CL61 User Guide

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User guide
  • Laptop with terminal software that supports SSH (for example, freeware TeraTerm or latest version of PuTTY)
  • Ethernet maintenance cable
Use of the maintenance connection is allowed only when maintenance operations are performed at qualified locations. CL61 does not comply with EMC standards when the door is open. The door has a conductive gasket to suppress electromagnetic radiation. When CL61 is used for normal operation, the door must always be closed.

The maintenance connection is established with the Ethernet maintenance cable included in the delivery, connecting the PC or laptop to the maintenance port of the ceilometer. The Ethernet maintenance port is located at the bottom of the measurement unit.

Push the plug into the port and turn 90° to lock in place.
The following steps use the PuTTY terminal software as an example.
  1. Connect your laptop to the maintenance port of CL61 with the Ethernet maintenance cable.

    Maintenance port: eth0

    Data port: eth1

    Figure 1. Measurement unit connectors, back of ceilometer
    Ethernet maintenance port (eth0)
    Ventilation plug
    AC/DC in
    Interface unit (control)
    Interface unit (data)
    CAUTION Remove the Ethernet maintenance cable after setup. It is not intended for permanent installation.
  2. Configure your computer settings to match the CL61 network settings.
    1. From your computer Control Panel, open Network and Internet or Network and Sharing Center.
    2. Select Change adapter settings.
    3. Right-click Ethernet and select Properties.
    4. Double-click Internet Protocol Version 4 (TCP/IPv4).
    5. Fill in IP address, Subnet mask, and Default gateway using the following computer settings.

      The following instructions use the default maintenance port IP address of Make sure that you know the IP address of the device you are establishing connection with.

      Property Value
      IP address
      Subnet mask
      Default gateway
    6. After configuring your computer settings, select OK on both pop-up windows to close them. The settings save and apply when the windows are closed.
  3. Open the command prompt app on your laptop.
  4. Test that you can connect to CL61 by typing the following in the command prompt.
  5. Open the terminal software.
  6. In the PuTTY Configuration window, type the following in Host Name: admin@

    Do not modify the other settings.

  7. Select Open.
  8. In the Security Alert window, accept the key.
  9. When prompted, type the admin password.
    For security reasons the password does not display in the interface window as you type it, but the keystrokes register.
    CAUTION If you forget the admin password, you cannot retrieve it without factory resetting the device (requires device activation code).