4100U-S1 Programming Guide
Document: LT0400
AS1668 Fan Controls
Page 10-4
15 December 2010
Issue 1.4
AS1668 Fan Manual Stop:
1. The 4100U-S1 panel receives indications from its AS1668 board that Fan #n rotary
switch state has changed to „Stop‟.
2. The 4100U-S1 panel commands the Multi-Point I/O to open the relay that controls
the fan to stop.
3. The Multi-Point I/O opens the relay to stop the fan.
4. The fan stops and air does not flow through the duct.
5. An air flow sensor in the duct sends to the panel via the Multi-Point I/O an indication
that the air flow is OFF.
6. The panel controls the AS1668 to turn the Green
“OFF” LED to ON and the Red
“ON” LED to OFF.
AS1668 Fan Faults:
Mechanical Services Board Faults:
1. The Mechanical Services Board sends a fault (e.g. mains failure) to the Multi-Point
I/O.
2. The Multi-Point I/O sends to the panel a fault condition.
3. The panel controls the AS1668 module to turn the amber
“FLT” LED to ON.
AS1668 Fan Start Failure:
1. The 4100U-S1 panel sends to the Multi-Point I/O a control to close the relay that
controls the fan to start (e.g. as result of Manual start or auto start).
2. The air flow sensor in the duct
does not
send to the panel an indication that the air
flow is ON.
3. After a programmable delay, to allow the fan to speed up.
4. The panel controls the AS1668 module to turn the amber Fault LED to ON.
AS1668 Fan Stop Failure:
1. The 4100U-S1 panel sends to the Multi-Point I/O a control to open the relay that
controls the fan to stop.
2. The air flow sensor in the duct
does not
send to the panel an indication via the Multi-
Point I/O that the air flow is OFF.
3. After a programmable delay, to allow the fan to slow down.
4. The panel controls the AS1668 module to turn the Amber Fault LED to ON.
