Honeywell UDC 3300 Product Manual page 150

Lower Display
Prompt
LOOPBACK
138
Upper Display
Range of Setting
or Selection
DISABL
ENABLE
UDC 3300 Process Controller Product Manual
Parameter
Definition
LOCAL LOOPBACK tests the communications hardware.
DISABLE—Disables the Loopback test.
ENABLE—Allows loopback test. The UDC goes into
Loopback mode in which it sends and receives its own
message. The UDC displays PASS or FAIL status in the
upper display and LOOPBACK in the lower display while
the test is running. The UDC will go into manual mode.
The test will run until the operator disables it here, or until
power is turned off and on.
ATTENTION The UDC does not have to be connected
to the RS-485 link to perform this test. If it is connected,
only one UDC 3300 should run the loopback test at a time.
The computer should not be transmitting on the link while
the loopback test is active.
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