Powtier Controls Limited
Air Curtain Controller
Instruction Manual
Alarms
The ACC raises an alarms if any of its inputs are outside their normal working scope.
The alarms are displayed on the Remote unit as an "alarm" code with a prefix "a".
The following are the list of alarms on the ACC.
Communication failure
Code 1 - this is triggered when the communication between the Base unit and the Remote unit
fails.
Air sensor too hot
Code 2 - this is triggered when the air sensor detects the ambient temperature above 60°C.
Air sensor failure
Code 4 - this is triggered when the air sensor is open circuit, typically when the air sensor is
broken or disconnected.
Heatsink too hot
Code 8 - this is triggered when the heatsink sensor detects the temperature of the heatsink
above 65°C.
Heatsink sensor failure
Code 16 - this is triggered when the heatsink sensor is open circuit, typically when the
heatsink sensor is broken or disconnected.
As the alarms are not mutually exclusive, the Alarm code displayed on the Remote unit are
accumulative. For example, if both air sensor failure (4) and heatsink sensor failure (16)
occur, the Remote unit will display "a 20" as the Alarm code.
Apart from the Communication failure alarm [Code 1], which could be due to a broken
connection of the RS485 link between the Base unit and the Remote unit, all other alarms will
cause the Base unit to switch off the heater output.
The ACC is protected from any short circuit on the air sensor or heatsink sensor as the short
circuit will cause the temperature to go high and trigger over temperature alarm.
ACCIM
Page 14
5 March 2007
Issue 1.4
