Frequently Asked Questions





What model Galvanic Isolator do I need?

DEI Isolators are typically applied using an industry standard method of matching the device to the steady-state current rating of the shore power service.  For a more detailed method of sizing your Galvanic Isolator, please visit our Product Selection Guide.

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What does the term "fail-safe" mean?

To be considered "fail-safe," an independent laboratory must confirm that the isolator will either remain fully functional or remain a permanent, effective grounding path if it fails when subject to the maximum current capability of the grounding conductor for a given galvanic isolator current rating. This provides guaranteed safety grounding, even when the product is failed, thus the "fail-safe" designation.

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What is the difference between Fail-Safe Plus and Fail-Safe MAX?

All DEI GIs are categorized as either Fail-Safe Plus® (FSP) or Fail-Safe Max® (FSM).  Fail-Safe Plus models not only meet the fail-safe test criteria in the A-28 standard, but also have considerably higher fault current ratings.

Fail-Safe Max models provide even higher AC fault current ratings than Fail-Safe Plus models and will still be functional and meet all other requirements of A-28 after being subject to the fail-safe test criteria, thereby providing the ultimate in performance and safety grounding.

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Do DEI products meet ABYC A-28 standards for Galvanic Isolators?

DEI Galvanic Isolators have been tested to meet or exceed all requirements of the  ABYC A-28 standard for fail-safe galvanic isolators and were certified by Imanna Laboratory. The scope of A-28 includes 30A through 100A isolators, so the DEI 200A model is not certified, but is designed to the same criteria as the certified models, but with a 200A continuous rating.

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Do DEI Galvanic Isolators need a monitoring system?

No. According to ABYC A-28, any isolator meeting the fail-safe criteria will not require a monitor due to the safety features built into the fail-safe device. 

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How do I register on the DEI website?

Registration is quick and easy. You may register by completing the required information on our registration form, found in the link above the navigation bar on our site.

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What do I do if I've forgotten my username and password?

At the login page there is an option to have your credentials sent to the email address that you registered with. Click on that link for further instructions or click here.

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What do I do if I don't find what I'm looking for on the DEI website?

Please feel free to send your request to us through our Contact Page, or by contacting us directly.

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Can I purchase DEI products online?

Yes.  You may purchase our products online by selecting the "Add to Cart" button found on all of our product page and following the instructions.  Dealers and resellers should use our Dealer Account Signup page to request a Dealer account.

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I am a dealer/reseller.  Can I setup an account?

Yes we offer dealer accounts through our website and you can request one using our Dealer Account Signup form.  You will be required to setup a website account, and provide a copy of a resale certificate for approval.

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How can I purchase DEI products?

DEI products are available for purchase online, and through our several stocking distributors around the world.  View our distributor list. 

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What do I do if I'm having trouble downloading product literature off of the DEI website?

Our literature is all available in .pdf format. In order to open these documents, you will need Adobe Reader installed on your computer. Adobe Reader is available free of charge from Adobe products, and can be downloaded by clicking on the following button.

If you are still experiencing problems, please contact the DEI office for

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