Warning
Hazard of Electric Shock: Remove all power from all devices before removing any covers or doors of the system. Disconnect power at the device and at the power source.
Electrostatic Discharge Required: Always discharge static electricity from your person by touching metal prior to handling any hardware. Failure to do so may result in damage to devices.
Issue
ACX5740 controller randomly re-boots and restore from flash, the controller does not attempt warm start but instead jumps directly to cool start.
Product Line
Andover Continuum
Environment
- Continuum ACX 2 Controller
- Continuum ACX 4 Controller
- Continuum Net Controller II
Cause
Door striker creating an electrical spike that can travel back down the output wiring to the controller. When this happens, it generally will not damage any of the hardware in the controller but it could cause it to reset or cause its memory to get scrambled.
The fact that the controller does not attempt warm start but instead skips directly to cool start is a strong indication that memory corruption is taking place, on startup, the controller verifies RAM memory is intact and will not attempt warm start otherwise.
Resolution
Install Metal Oxide Varistor (MOV ) to add voltage suppression to the controller's output driving the door striker.
(Put the MOVs at the end device and not the controller end)
Another option is to add an isolation relay to keep the electrical noise from reaching the controller's output.
