United Electric Controls ONE Series, Инструкция по установке и обслуживанию

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D. The 4-20mA output signal does not appear
to be functioning
Intent: To locate load element, interconnection, or One Series fault
Question
1. Turn off all power to the unit and verify the
connections are correct and secure (See Wiring
Diagrams)
2. Remove the current loop load wire. Using an
ohmmeter, measure the resistance of the cur-
rent loop load (4-20mA load connection to
Ground). Is this value less than 500 ohms?
3. Connect a milliamp meter in series with the
current loop circuit and apply power to the One
Series. Does the 4-20mA output function prop-
erly?
4. Turn off power and disconnect the current
loop connection to the load device. Connect the
meter from the 4-20MA output connection to
the Ground connection. Reapply power - does
the 4-20mA output function properly?
Answer
Yes
No
Yes
No
Yes
No
Yes
No
Direction
Go to step D2
Correct and secure wires. Go to
step D2
Go to step D3
Check the load connections to
ensure proper and secure con-
nections. If the current loop
load exceeds 500 ohms, correct
current loop connections and
loading. Go to Step D3.
Remove milliamp meter and
reconnect wires. Done
Go to step D4
Remove milliamp meter and
reconnect wires. Done
Contact United Electric Controls
or their authorized Distributor
for further assistance.
E. The display reads: VALUE > SET POINT
Intent: Determine correctness of One Series Measurement/Message
This indicates that the measured process variable has exceeded the Set Point
value and is currently more than the Set Point value minus the Deadband value.
The output has "tripped" (either "ON" or "OFF" based on the Switch Output Mode
selection) and has not reset.
Verify Set Point, Deadband,
Switch Output Mode settings
and Process Variable
F. The display reads: VALUE < SET POINT
Intent: Determine correctness of One Series Measurement/Message
This indicates that the measured process variable reached the Set Point value and
is currently not greater than the Set Point value plus the Deadband value. The
output has "tripped" (either "ON" or "OFF" based on the Switch Output Mode
selection) and has not reset.
Verify Set Point, Deadband,
Switch Output Mode settings
and Process variable