nVent RAYCHEM Elexant 4010i/4020i User Manual
RAYCHEM-AR-H60624-40X0iOpsManual-EN-1905
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Values
Description
Default Value
Range
High Trace Current
This alarm is active when the trace current
level has surpassed the value of High
Trace Current Setpoint.
30.0 A
0.1 A to 100.0 A
Low Trace Current
This alarm is active when the trace current
level has dropped below the value of Low
Trace Current Setpoint.
1.0 A
0.1 A to 100.0 A
Table 24 - High/Low Trace Current Alarm Settings
In the case of a 3-phase controller; L1, L2 and L3 buttons are displayed in the top right corner of the
page. Touching any of these buttons displays the corresponding settings for that Line current. Enabling
the
Balanced 3 Phase
option disables individual High/Low Trace Current Alarms for phases 2 and 3, and
uses the values for phase 1 for all three phases.
Figure 104 - Trace Current Page for 3-Phase Heat Trace Circuit
NOTE:
If the Trace Current tab is flashing and the setpoint value is highlighted in red, its setting is invalid.
Check the Current Turns Ratio and adjust its setting within the correct range.
5.8.1.2
Current Turns Ratio
Purpose:
The Current Turns Ratio adjusts current readings for applications where a control module is monitoring a
load through an external step-up or step-down current transformer.
The highest Trace Current supported by the controller is a function of the external Current Turns Ratio.
This field can be used to multiply or divide the Trace Current.
Figure 105 - Current Turns Ratio Setting
Range:
0.1 to 10A
Default:
1.00
Procedure:
•
Adjust the Current Turns Ratio (CTR) to equal the ratio of the primary to secondary windings of the
external current transformer
•
After setting the Current Turns Ratio, compare the current indicated by the controller to the actual mea
-
sured heat trace current and adjust the CTR until the two readings are as close as possible
IMPORTANT:
When the Current Turns Ratio has been set appropriately, the control unit will calculate the
heat trace circuit power using the adjusted current and voltage readings. Current alarms also use the
adjusted current reading.