LiftMaster MAT-DC-BB3 Mega-Arm

Question: Greg out of Georgia wanted to know: We have a client that has a pair of your MAT-DC-BB3 Mega-Arm units that are integrated with a Lenel On-Guard access control system. There are no ground loops or sensors; the arm is programmed to close after a few seconds. There are hardwired open and close buttons as well. The client is experiencing a problem where the arm has closed faster vehicles could get out of the way. I have downloaded the installation manual but have not had an opportunity to review it in its entirety. In the meantime, is there a way that the arm can be set up where the only way to close it is through the button, manually (even if the access control system opens it)?

Answer: Good afternoon Greg, as a matter of fact yes there is a way to turn that feature off…

  1. Disconnect one side of the battery lead
  2. Turn Power OFF
  3. Located switch bank labeled S2
  4. Turn OFF switch number 7 on S2 switch bank
  5. Turn Power back ON
  6. Reconnect battery
That should have deactivated the auto close feature on your mega-arm.