Quest Controls 600 - Page 34

Rev 3.1 01/11/23 - 29 - Model 600 User Guide
Function Code
Register
Description
Read/
Write
Type Default
Notes
Non-volatile
17
Control Voltage Lost Alarm
RO bit N/A
1 off, 0 on. Output energized when
not in alarm.
N
Operation/Status
Holding Register
(FC3/6/16)
100 Controlling Temperature RW word
Write will override internally
calculated value based on Reg 1001.
Write of 65535 will resume local
operation.
N
101 Outside Air Temperature RW word
Write will override internally
calculated value.
Write of 65535 will resume local
operation.
N
102 Operational Cooling Setpoint RW word
Write will override internally
calculated value.
Write of 65535 will resume local
operation.
N
103 Operational Econ Setpoint RW word
Write will override internally
calculated value.
Write of 65535 will resume local
operation.
N
104 Operational Heating Setpoint RW word
Write will override internally
calculated value.
Write of 65535 will resume local
operation.
N
105 Model 600 Control Mode R word N/A
Enumerated low byte: 1 = Heat 2, 2
= Heat 1, 3 = Off, 4 = Econ 1, 5 =
Econ 2, 5 = Cool 1, 6 = Cool 2, 7 =
Cool 3, 8 = Cool 4
N
106 HVAC Bypass Mode RW word N/A
Enumerated low byte: 1 = Heat 1, 2
= Off, 3 = Econ, 4 = Cool 1, 5 = Cool
2.
High byte is the number of minutes
for bypass or 0 for return to local
operation.
N