Watlow F4T  •  232  •  Chapter 6 Appendix
Parameter Class 
and Name
Range Default
Data Type and 
Attributes
Modbus Registers
Control Mode Active
"Off (62) 
Auto (10) 
Manual (54)"
"unsigned 16-bit 
Access = R"
"Cascade Loop 1: 4012 
Cascade Loop n: 
4012+((n-1)* 200)"
Control Action
"Off (62) 
Cool (20) 
Heat (36) 
Both (13)"
Heat (36)
"unsigned 16-bit 
Access = RW"
"Cascade Loop 1: 4014 
Cascade Loop n: 
4014+((n-1)* 200)"
Autotune 
Aggressiveness
"Under (99) 
Critical (21) 
Over (69)"
Critical (21)
"unsigned 16-bit 
Access = RW"
"Cascade Loop 1: 4016 
Cascade Loop n: 
4016+((n-1)* 200)"
Autotune Set Point  50 To  200% 90.0
"IEEE Float 
 Access=RW"
"Cascade Loop 1: 4018 
Cascade Loop n: 
4018+((n-1)* 200)"
Autotune
"No (59) 
Yes (106)"
No (59)
"unsigned 16-bit 
Access = RW"
"Cascade Loop 1: 4020 
Cascade Loop n: 
4020+((n-1)* 200)"
Autotune Status
"Off (62) 
Waiting For Cross 1+ 
(119) 
Waiting For Cross 1- 
(120) 
Waiting For Cross 2+ 
(121) 
Waiting For Cross 2- 
(122) 
Waiting For Cross 3+ 
(123) 
Waiting For Cross 3- 
(150) 
Measuring Max Peak 
(151) 
Measuring Min Peak 
(152) 
Calculating (153) 
Complete (18) 
Timeout (118)"
"unsigned 16-bit 
Access = R"
"Cascade Loop 1: 4022 
Cascade Loop n: 
4022+((n-1)* 200)"
Open Loop Detect 
Enable
"No (59) 
Yes (106)"
No (59)
"unsigned 16-bit 
Access = RW"
"Cascade Loop 1: 4024 
Cascade Loop n: 
4024+((n-1)* 200)"
Open Loop Detect 
Time
 0 To  9999 240
"unsigned 16-bit 
 Access=RW"
"Cascade Loop 1: 4026 
Cascade Loop n: 
4026+((n-1)* 200)"
Open Loop Detect 
Deviation
-99,999.000 to 99,999.000°F 
or units, -55,555.000 to 
55,555.000°C
10.0
"IEEE Float 
 Access=RW"
"Cascade Loop 1: 4028 
Cascade Loop n: 
4028+((n-1)* 200)"
Control Loop Error
"None (61) 
Open Loop (1274) 
Reversed Loop (1275)"
"unsigned 16-bit 
Access = R"
"Cascade Loop 1: 4030 
Cascade Loop n: 
4030+((n-1)* 200)"
Clear Error
"Clear (129) 
Ignore (204)"
Ignore (204)
"unsigned 16-bit 
Access = RW"
"Cascade Loop 1: 4032 
Cascade Loop n: 
4032+((n-1)* 200)"
Minimum Set Point
-99,999.000 to 99,999.000°F 
or units, -55,572.778 to 
55,537.222°C
-99,999.000°F or 
units, -55,572.8°C
"IEEE Float 
 Access=RW"
"Cascade Loop 1: 4034 
Cascade Loop n: 
4034+((n-1)* 200)"
Maximum Set Point
-99,999.000 to 99,999.000°F 
or units, -55,572.778 to 
55,537.222°C
99,999.000°F or units, 
55,537.2°C
"IEEE Float 
 Access=RW"
"Cascade Loop 1: 4036 
Cascade Loop n: 
4036+((n-1)* 200)"