29
ST 5220
QM 1336.rev.01
3
Adjusting Stage 2 Bandwidth
The Stage 2 bandwidth is the temperature interval within which the Stage 2
variable speed fans increase or decrease in speed proportionally to the
temperature (see the diagram above). The bandwidth can be adjusted
between 0.5°F and 20.0°F (0.3°C and 11.1°C).
n
Set the selection knob to STAGE 2 — BANDWIDTH. The current
bandwidth for Stage 2 is displayed, alternating with the letters "bd".
n
Use the adjustment knob to adjust the bandwidth to the desired value.
4
Adjusting Stage 2 Minimum Speed
The minimum speed can be adjusted between 10% and 100% of the full speed
of the fans.
n
Set the selection knob to STAGE 2 — MINIMUM SPEED. The current
minimum speed for Stage 2 flashes on the display.
n
Use the adjustment knob to adjust the minimum speed to the desired
value.
5
Adjusting the Stage 3 Starting Temperature
The Stage 3 starting temperature is the temperature at which the Stage 3 fans
start running (see the diagram above). The hysteresis is fixed at 1.5
o
F and
determines when the fans return to a stop. The difference between the starting
temperature and the Stage 2 starting tempe bandwidth can go from
0.5°F to 20.0°F (0.3°C to 11.1°C).
n
Set the selection knob to STAGE 3 — START TEMP. The current Stage
3 starting temperature is displayed, alternating with the letters "ST3".
n
Use the adjustment knob to adjust the temperature to the desired value.
