Design Guide for Hazardous / Industrial
Self-regulating trace heating systems
21-1S00-7D0001/-
05/2023-EHT-466853
Notice Technical data subject to change without notice.
No claims for damage arising from alternations, errors or misprints shall be allowed.
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The following table shows the maximum sum of trace heater lengths per branch circuit when connected to power through one or more system
junction boxes.
If feeding multiple trace heating system circuits from the single circuit breaker, the maximum sum of trace heater lengths can then be extended.
Please refer to BARTEC Heloc Pro design software or contact BARTEC technical support.
Breaker sizing should be based on international electric codes or any other local or applicable code. Use only circuit breakers with type C tripping
characteristics.
WARNING
Risk of fire, electrical shock or dysfunction. Observe the maximum amperage of all components of the trace heating circuit. If the required trace
heater length exceeds the maximum heating circuit length you must install multiple heating circuits.
The following tables G1 and G2 must be observed when selecting the max. heating circuit length.
Table G1 considers the fuse protection in relation to the min. switch-on temperature.
Table G2 considers the fuse protection in relation to the max. ambient temperature of the enclosure in which the heating cable is connected. The
table refers to the Limitation of Operating Current (stady state) of the trace heating circuit at Tamb max [A].
Finally, the determined shorter length from both tables is to be applied.
Table G1: Maximum heating circuit length for circuit breakers with Type C tripping characteristics
Circuit
breaker size
Start-up
temperature
PSB trace heaters
Operating voltage: 230 Vac
3PSB2
5PSB2
8PSB2
10PSB2
16 A
+10 °C
202 m
153 m
91 m
57 m
0 °C
202 m
144 m
86 m
54 m
-20 °C
163 m
115 m
70 m
44 m
20 A
+10 °C
202 m
165 m
120 m
76 m
0 °C
202 m
165 m
107 m
67 m
-20 °C
202 m
144 m
87 m
55 m
25 A
+10 °C
202 m
165 m
128 m
95 m
0 °C
202 m
165 m
128 m
84 m
-20 °C
202 m
165 m
109 m
69 m
32 A
+10 °C
202 m
165 m
128 m
97 m
0 °C
202 m
165 m
128 m
97 m
-20 °C
202 m
165 m
128 m
88 m
Circuit
breaker size
Start-up
temperature
MSB trace heaters
Operating voltage: 230 Vac
3MSB2
5MSB2
10MSB2
15MSB2
20MSB2
16 A
+10 °C
230 m
164 m
92 m
67 m
52 m
0 °C
217 m
155 m
87 m
64 m
49 m
-20 °C
195 m
141 m
79 m
58 m
45 m
20 A
+10 °C
231 m
188 m
115 m
82 m
65 m
0 °C
231 m
188 m
109 m
79 m
61 m
-20 °C
231 m
177 m
98 m
72 m
56 m
25 A
+10 °C
231 m
188 m
133 m
82 m
75 m
0 °C
231 m
188 m
133 m
82 m
75 m
-20 °C
231 m
188 m
123 m
82 m
70 m
32 A
+10 °C
231 m
188 m
133 m
82 m
75 m
0 °C
231 m
188 m
133 m
82 m
75 m
-20 °C
231 m
188 m
133 m
82 m
75 m
