Thermon TraceNet TCM 18 User Manual
Page 89
Example D4 - Process Temperature Control - Mechanical Relays
Extremely versatile, the TCM18 can be configured with RM-6 mechanical relay out-
put options. This option is often selected in high heat output tracing applications
where either high current or high voltage switching is required. One such tracing ap-
plication might be the temperature maintenance of a long sulfur transfer line. Typical
tracing design requirements are listed as follows:
Heater Cable
Mineral Insulated Series Cable
Voltage Switched:
277 Vac
Current Switched:
49A
Sulfur Maintain Temperature:
282
◦
F (139
◦
C)
Sulfur Freeze Point:
260
◦
F (127
◦
C)
Sulfur Congeal Point:
320
◦
F (160
◦
C)
The TCM18 control module with pipe sensing RTD’s could be typically as shown
below:
Control Parameter
Setting
Controller Configuration
Single RTD Pipe Sensor
Control Method
On/Off
Maintain Temperature
282
◦
F (139
◦
C)
Control Band
9
◦
F (5
◦
C)
High Alarm Temperature
300
◦
F (149
◦
C)
Low Alarm Temperature
260
◦
F (127
◦
C)
Having set in these values as well as the appropriate other limit/control values, the
following typical control can be achieved.
85
PN 50316_0514