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Communicates digitally with Vulcain transmitters within a true daisy chain network, converting the digital signals to analog outputs.
Features and Benefits
  • Easy installation through daisy chain hook up (RS-485)
  • Dedicated 4-20mA outputs for up to 8 transmitters
  • Averaging/minimum/maximum reading for up to 16 transmitters
Quick Specs
  • Power requirement: 17-24 VAC, 24-38 VDC, 500 mA
  • Size: 8.4 (H) x 8.6 (W) x 2.5 (D) in. (21.3 cm x 13.4 cm x 5.7 cm)
  • Operating humidity range: 0 to 95% RH, non-condensing
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Additional Information

Product Overview

The 420I communicates digitally with Vulcain transmitters within a true daisy chain network, converting the transmitters’ digital signals to analog outputs. This allows each transmitter to provide a 4-20mA signal to a BMS from one central location. The unit can accommodate up to eight transmitters installed at distances of up to 2 000 feet from the unit.

To avoid expensive DDC hook-ups and BMS software upgrades, the unit even comes with internal logic that will provide averaging/minimum/maximum reading for up to 16 transmitters.

Frequently Asked Questions

Have a question about the product features or warranty? Find the answers here.
We do not sell our products directly on our website but we would be happy to assist you with your gas detection needs.  On each product page you will see a red button on the right-hand side titled “HOW TO BUY”.  If you click on this button a form will appear which will go directly to one of our sales representatives once completed and submitted.  

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You can also access the technical documents for each product on that product’s respective page within the website.    

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There are several ways you can search for products on our website:

  • Click on the Products link in the main navigation to search by product lines.
  • Find products for a specific Industry or Application by clicking on the links in the main navigation bar at the top of the page.
  • Use our Gas Finder if you’re looking for a product that can detect a specific type of gas.
  • If you still can’t find the product you’re looking for, type the name of the product in the search bar at the top of the page.

Because we do not sell our products directly we cannot quote a specific price on our website.  Contact a sales representative through either the “HOW TO BUY” button on the product page or by calling them and they will be able to obtain pricing from local distributors in your area. 

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Looking For More Information?

Check out these documents. If you can't find what you're looking for here, check out our Technical Resource library.