[KBA-01248] HID EVO EH400-K Units Intermittently Misread Badges - HID


[KBA-01248] HID EVO EH400-K Units Intermittently Misread Badges

This article explains why an HID EVO EH400-K unit might sometimes fail to properly read an access badge.


When presenting access badges to an HID EVO EH400-K unit, cardholders who are usually allowed through are denied access, and Security Desk claims it does not recognize the card format.

More Information

This is due to noise from the HID unit's power supply.

Try one of the three options below when choosing cable shielding:

  • Independently shield the reader cable only; this reduces noise and increases reliability.
  • Independently shield the lock cable only; keeps the noise, but increases reliability.
  • Shield both cables. In this scenario, tie the reader shield to the controller or the Wiegand module connection, and leave the lock shield floating.

A design change addressing the issue is now fully cut into HID manufacturing for both new and reworked products. Identify “good” (products with fix) and “bad” (products without fix) using the information in HID's Technical bulletin published below.

For additional info, refer to this document from HID and the following exception list.

Exception list found in multiple worksheets within this Excel