Commercial Building Solutions

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301C Controller

Designed for simple installation and operation, the 301C continuously monitors and controls toxic gases, combustible gases and oxygen hazards.
Features and Benefits
  •  User friendly with zero maintenance
  •  Low installation costs
  •  Automatic quick self-test and warm-up
Quick Specs
  •  Power requirement: 17-27 VAC, 24-38 VDC, 500 mA
  •  Size: 11 (W) x 8 (H) x 2.8 (D) in. (28 x 20.3 x 7 cm)
  •  Weight: 2.4 lbs. (1.1 kg)
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Product Overview

Using an addressable RS-485 Modbus communication protocol, the 301C uses daisy chain wiring requiring only 2 pairs of wires to connect up to 96 transmitters on the 3 input channels. This simplifies installation, in turn lowering costs. The 301C’s zoning and averaging abilities significantly reduce operational and maintenance costs.

Zoning / Averaging
The 301C controller offers unique zoning capabilities which permit the averaging and comparison of multiple sensor readings. Zoning can reduce operational costs by ensuring that localized brief fluctuations registered at a single transmitter do not activate relays. For example, a car idling in a parking structure may locally increase a reading at a nearby transmitter. Rather than activating a fan as a result of the temporary localized fluctuation, zoning can be used to limit relay activation until the average reading for a zone exceeds a set-point. This can reduce run time of fans, yielding savings in both energy usage and wear and tear. The 301C has the capacity to manage input from three Modbus channels for up to 96 transmitters and up to 50 wireless transmitters that can be associated with up to 126 zones. Transmitters can belong to an unlimited number of zones, providing maximum operational and control flexibility.

Additional Features and Benefits:

User Friendly
  • Zero maintenance
  • User Friendly
  • Automatic quick self-test and warm-up
  • Continuous alphanumeric display


Inexpensive and Reliable

  • Low installation costs
  • Allows for up to 126 zoning groups which can save energy and extend fan and relay life
  • Manages up to 768 events with programmable latching alarms


Flexible Operation
  • Optional BACnet/IP available
  • Interchangeable transmitters able to detect different gases
  • Expands to handle up to 96 transmitters or relay modules
  • Programmable time delays
  • Integrated time clock enables scheduling of system operations


Safety Measures
  • Full array of visual indicators and integrated 65dBA alarm levels
  • Fully programmable relays (can be set as fail-safe or not)


Beneficial Options
  • Available in a heavy-duty industrial housing
  • Datalogging option
Control oxygen hazards - 301C Controller - Honeywell Analytics

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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.  

You can also call one of our sales representatives directly.  Click here to go to the Contact Us page.  

There are two areas where you can access technical documents.  First, you can visit our Technical Library in the Support section of the website.  Here you will be able to access our entire catalog of documents and videos for all products – current and legacy products.  

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

Yes we do.  Check out our HA University training section to see what programs are available and sign up for any that you are interested in.  These courses are very informative and led by our expert engineers.  If you have any questions about training opportunities for yourself or your staff and would like to talk to a Honeywell representative, click here.

Check out the Product Inquiry page in the Contact Us section.  Here you’ll find sales contacts for each of our product lines and they can help you with any questions you may have from technical specifications to ordering information. 

Check out the Service & Repairs page in the Contact Us section.  Here you’ll find the contact information for our service centers in your region. 

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.