User manual

SEC-HD user manual Configuring the stages
23
Configuring the stages
Your SEC-HD has three types of stages: two variable stages, three relay (ON/OFF) stages, and one
inlet actuator stage.
Configuring variable stages, parameters 19 and 20
Variable stages 1 and 2 control elements that operate with gradually changing voltage, such as
variable speed fans. There are three configuration options.
 Off (
0ff
) – the variable stage is always off.
 Cooling 1 (
( L 1
) – the stage controls a variable speed fan using motor curve 1. Use motor
curve 1 for most fans.
 Cooling 2 to Cooling 4 (
( L 2
, and so on) – the stage controls a variable speed fan using
selected motor curve. Use one of motor curves 2 to 4 only if one of the following problems
occur when using manual override to test.
 The fan changes speed only within a small portion of the 0 to 100% range
 The fan runs at full speed regardless of the 0 to 100% range
Default: stage 1 and 2 cool
 For more information about motor curves, including a table cross-referencing
fan motors with recommended curves, read Appendix G: Motor curves on page
59.
 Use the Variable stage configuration worksheet on page 56 when configuring
variable stages.
 For more information about how variable stages work, read Programming
variable stages on page 30.
To configure variable stages
1. Press Program until
( 0 N f
displays and then press Select.
The display shows
17
, the first item in the Configuration menu.
2. Press Up until
19
displays for variable 1 (or
20
for variable 2) and
then press Select.
The display shows the current configuration.
3. Press Up or Down until the configuration you want is displayed and
then press Select.
The control returns to the Configuration menu.
4. To return to the Main menu, press Back once. To return to the
Main display, press Back twice.
Increase voltage
(0Nf
“L 1