Nor-Cal SDC15 Controller - Manual (Page 62)

■ Control action and Heat/Cool control
The control action (direct/reverse) and Heat/Cool control (enabled/disabled) can
be selected.
• When the control method is other than the ON/OFF control (CtrL ≠ 0),
[Heat/Cool control: C26] can be displayed and set.
• When the Heat/Cool control is set disabled (C26 = 0), [Control action: C14] can
be displayed and set.
• When the Heat/Cool control is set enabled (C26 = 1), the control action is
changed to the reverse action (C14 = 0), the preset MANUAL value (C20) is
changed to "50.0", and the initial output of PID control (C22) is changed to
"50.0".
• The reverse action (heat control) is a control that decreases (or turns OFF) the
manipulated variable (MV) as the PV increases.
The direct action (cool control) is a control that increases (or turns ON) the
manipulated variable (MV) as the PV increases.
■ Special control outputs
The control output at PV alarm and control output at READY can be set.
• When the control method is other than the ON/OFF control (CtrL ≠ 0) and the
Heat/Cool control is set enabled (C26 = 1), [Output at READY (cool): C18] can
be displayed and set.
• The PV alarm status means that AL01, 02, or 03 occurs.
5-12
Chapter 5. DETAILED DESCRIPTION OF EACH FUNCTION
Item (Setting display/bank) Display Contents Initial value User level
Control action
(direct/reverse)
(Setup setting/Setup bank) 0: Heat control (Reverse)
1: Cool control (Direct) 0 Simple,
Standard,
High function
Heat/Cool control
(Setup setting/Setup bank) 0 Simple,
Standard,
High function 0: Disabled.
1: Enabled.
Item (Setting display/bank) Display Contents Initial value User level
Output operation at PV
alarm
(Setup setting/Setup bank) 0: Control calculation is continued.
1: Output at PV alarm is output. 0 High function
Output at PV alarm
(Setup setting/Setup bank) 0.0% High function -10.0 to +110.0%
Output at READY (Heat)
(Setup setting/Setup bank) 0.0% Standard,
High function -10.0 to +110.0%
Output at READY (Cool)
(Setup setting/Setup bank) 0.0% Standard,
High function -10.0 to +110.0%