nVent RAYCHEM Elexant 4010i/4020i User Manual
RAYCHEM-AR-H60624-40X0iOpsManual-EN-1905
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Trace Current
Trace Voltage
Ground Fault Current
These readings inform the operator of the highest and lowest readings the controller has detected during
operation.
3.2.3.8 Preventative Maintenance
The controller includes a feature to manually run a Trace Test. This will apply power to the heating circuit
for a period of time (default is 180 seconds) and then turn it off.
Autocycle is similar to Trace Test. It applies power to the heating circuit for 30 seconds at the selected
interval, typically 8 hours.
Both Trace Test and Autocycle serve to verify the heating circuit integrity. Unlike Autocycle, Trace Test
can be run at any time. Both force the output to be ON, assuming there are no higher priority overrides
inhibiting this (e.g. Ground Fault, Current Transformer Failure).
IMPORTANT:
The Elexant 4020i Safety Limiter units meet the requirements of SIL2 as set out in
IEC61508:2010. In accordance with this standard, units must be subjected to a functional test after
commissioning, at regular intervals, in order to guarantee safe and reliable operation. The functional test
procedure is covered in Section 4.1.9.
3.2.4
External Devices
3.2.4.1 Digital Input
The Digital Input allows simple external devices to extend the functionality of the controller. It offers
the option to alarm or override the electrical heat-tracing mode from an external device and can be
configured in the following ways:
•
None (Default): No action taken or no device connected.
•
Force On when input is open or closed (Open/closed is also configurable).
•
Force Off when input is open or closed (Open/closed is also configurable).
•
Alarm when input is open or closed (Open/closed is also configurable).
•
Hand/Off/Auto – this allows connection of an HOA switch that can be used to configure the controller
output as follows:
–
Hand - manually override the normal control output decision and turn the output on
– Off – manually override the normal control output decision and turn the output off.
– Auto – no override, control output decision is made by the controller as per normal operation.
3.3
COMMUNICATION
The Elexant 4010i/4020i can be connected to a network via Modbus or Profibus to
provide remote connectivity to the controller. This enables the user to view and edit the controller’s
configuration, alarm status, and view real-time data from a remote location.
3.3.1 Modbus
The industry-standard master-slave Modbus RTU protocol is used with RS-485 communications, and
Modbus/TCP is supported for use with Ethernet connections.
3.3.1.1 RS-485
The Modbus RTU protocol on an RS-485 link may be used to communicate with devices such as the
nVent RAYCHEM TOUCH 1500 or nvent RAYCHEM Supervisor. The RS-485 configuration parameters and
defaults are shown below.
