AMX VST Instruction Manual page 23

Thermostat Action Commands (Cont.)
Command
SC++/SC --
Increment Or Decrement
Temperature Setting - Cool
S
Current Mode Temperature Set-
ting
SP++/SP --
Increment Or Decrement Current
Mode Temperature Setting
ViewStat Communicating Thermostat - Programming Protocol Reference Guide
Description
These commands are used to raise (SC++) or lower the (SC--) the cool
temperature setting by a specified value. The value is assumed to be in
the temperature scale set using the SCALE command and the response
will include a scale designator. Should the resultant change be outside the
allowable range for the set temperature scale, the command will be
ignored.
Syntax:
SN[address] SC++={value}F or C or SC--={value}F or C
Reply Format:
SN[address] SC++=Integer value F or C
or SC--=Integer value F or C
The ViewStat holds two temperature settings in memory: a heat setting
and a cool setting. In the Heat mode of operation, the heat setting is used
as the control point and in the Cool mode of operation the cool setting is
the control point. In the Auto mode of operation the thermostat will control
the temperature using either the heat setting or the cool setting depending
on which the current room temperature is closest. The Setpoint (S) com-
mand is used to change the active temperature setting, so knowledge of
the current mode of operation is not required. If the thermostat is currently
in the Heat mode, the heat setting will be changed. If the thermostat is in
the Cool mode the cool setting will be changed. If the thermostat is in the
Auto mode, the temperature setting corresponding to the last HVAC equip-
ment call (i.e. current active reversing valve output). The thermostat will
automatically maintain a two degree (2°) difference between the heating
and cooling settings regardless of which mode of operation is currently
active, by raising or lowering the value not being adjusted if the two degree
separation rule is violated by this command.
Syntax:
SN[address] S={value}
Variable:
• {value}: Integer value F or C - see Heat (SH) and Cool (SC) Setting
commands for allowable range.
Reply Format:
SN[address] SH={value} or SC={value}; depending on which
value was changed.
These commands are used to raise (SP++) or lower the (SP--) the current
mode temperature setting by a specified value. The value is assumed to
be in the temperature scale set using the SCALE command and the
response will include a scale designator. Should the resultant change be
outside the allowable range for the set temperature scale, the command
will be ignored.
Syntax:
SN[address] SP++=Integer value F
or C or SP--=Integer value F or C
Reply Format:
SN[address] SP++=Integer value F or C
or SP--=Integer value F or C
ViewStat Programming Protocol
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