MatrixMonitor™ IOM - Rev 4 - 4/11/2013
Page 18
Set the Fan Status
The fan status flag is used by MatrixMonitor™ to correctly calculate the array airflow in the event that it
detects a fan is not operating and to properly set the fan failure alarm. The control unit monitors the
piezometric port pressure of each fan. When a fan fans not operating, the port pressure is considerably
lower than the other fans in the array which tells the control unit that the fan is not running.
The internal data stored for each fan model allow the control unit to calculate the amount of air flowing
backwards through the fan when it is not operating. Matrix monitor knows a back flow prevention
damper is installed when the damper flag is set (see “Set the Optional Dampers” above).
The fan status flag is used by the MatrixMonitor™ software to control how it reacts when it determines
a fan is not operating.
If the fan status flag is set to “
On
”, the control assumes that the fan has failed and sets the fan failure
alarm. A fan failure alarm will turn on the fan failure relay, light the red LED lamp on the keypad and
respond to a BMS inquiry that a fan failure has occurred. The calculated backflow will subtracted from
the flow totaled from the rest of the fans if back flow prevention dampers are not installed. If dampers
are installed, the flow for this fan is set to 0.
If the fan status flag is set to “
Off
” the control assumes that the fan is off for a reason and does not set a
fan failure alarm. The calculated backflow will subtracted from the flow totaled from the rest of the fans
if back flow prevention dampers are not installed. If dampers are installed, the flow for this fan is set to
0.
If the fan status is set to “
Blanked Off
” the control
assumes that the fan is off and a blank off plate has
been installed on the inlet to prevent backflow. The fan
failure alarm is not set and the flow for the fan is set to
0.
The default status for all fans is “
On
”. The “
Off
” status is
for the user to inhibit the fan failure alarm. This is useful
after the failure has been acknowledged to clear the
alarm. It is also useful if a fan has been shut down for
capacity or maintenance purposes. The “
Blanked Off
”
status is for the same purpose but allows the control to
calculate array airflow correctly when the fan has a
blank off plate installed.
From the “
Array 1 Options
” submenu, scroll down to highlight “
7. Set Fan Status
”. Press the
(enter) key and the fan status setup screen will appear. The first line on the screen will display the array
name. (It should have been set in a previous step) The second line on the screen will read “
Fan 1: On
”.
The number before the colon (:) is the selected fan. This can be scrolled through all of the fans in the