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NetGuardian 420

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The NetGuardian 420 is our full-featured, medium-capacity RTU. It monitors 20 discrete alarms, up to 6 analogs, up to 32 network elements, and 4 relays.

Key Features

  • Monitors up to 8 analogs
  • Controls up to 4 relays
  • Medium-capacity RTU with 20 discrete alarm points
  • Pings up to 32 network elements
  • Manage your network with a built-in web interface

Do you need an RTU to keep an eye on your remote network? Do you need more than just a few alarm points but a high-capacity device is overkill?

If you have sites that are not exactly small, but you'll never be able to use all the capacity of a large RTU, you need an "in-between" device. Of course, no matter its capacity, your device should still provide you with advanced features and capabilities, such as a built-in terminal server.

This is exactly the type of scenario that the NetGuardian 420 was designed for.

This "just right" SNMP RTU has 20 discrete inputs to gather all alarms from multiple equipment and up to 6 analog inputs for monitoring sensors, battery levels, generator fuel levels, and any other important value.

Also, it comes with a built-in terminal server for remotely accessing your serial gear. This is an important feature that helps you avoid costly telecom truck rolls.

The NetGuardian 420 is our first medium RTU designed to have less capacity than the NetGuardian 832A G5 and more capacity (25% more) than the NetGuardian 216. The 420 is an advanced RTU that is as intuitive and advanced as the 832A G5. This means that the NetGuardian 420 is SNMPv3-capable, has RADIUS authentication feature, and a 4-port terminal server.

Are you hesitant to invest in the 420 RTU because you think you may need more capacity in the future? Don't worry. As your network grows, you can gain flexibility by using a NetGuardian DX Expansion to add on to your discrete alarm capacity. You can add up to 3 expansion units, as you need them, and reach a total of 164 discrete points.

Form Factor

  • Height: 1.75"
  • Width: 17"
  • Depth: 7.5"
  • Mounting:
  • Weight: 3.5 lbs

Core Features

  • 19-Inch Rack Ears
  • 23-Inch Rack Ears
  • Analog Alarms: 6
  • Control Relays: 4
  • Discrete Alarms: 20
  • Ground Isolated
  • LCD Display
  • Ping Alarms: 32
  • Power Supply: -48Vdc
  • Rack Ears: Both
  • RoHS: 5/6
  • RTC
  • Temp. Probe
  • Web Browser Interface

Operating Conditions

  • Max. Current: 1 Amp, AC/DC
  • Max. Voltage: 60VDC / 120VAC
  • Operating Humidity: 0% -95% non-condensing
  • Temperature: 32 to 140F (0 to 60C)

Optional Features

  • 12V Sensor Power Supply
  • D-Wire: 1-Plug
  • Industrial Temp.
  • NIC: 10/100BaseT
  • Power Input: Dual
  • Power Supply: +24Vdc, -24/48Vdc (wide range), -24Vdc
  • Serial Port: RS232, RS485
  • Temp/Battery Monitoring
No additional software required.

Use the built-in web interface for configuration. Monitor via web interface, your SNMP manager, or a T/Mon master station.