Emerson Tescom ER5000 Series User Manual page 181

ER5000 — The ERTune™ Program: Basic Features
The Control Limits Panel
The entry fields in this panel allow you to set system Control
Limits which the ER5000 will then monitor.
The ER5000, in addition to its control function, can also be
configured to monitor when operational or mechanical limits of
the system have been exceeded. When the controller detects a
signal that exceeds a set limit, it activates the internal solenoid
valves to reach one of three Control Limit Conditions:
• Inlet Closed/Exhaust Closed
• Inlet Closed/Exhaust Open
• Inlet Open/Exhaust Closed
The Control Limit Conditions provide added security in the event
of a system failure such as broken transducer wiring, lack of supply
pressure or pipe ruptures.
The default Condition is Inlet Closed/Exhaust Open, which
ensures that a pressure reducing system will be vented if a limit is
exceeded. If your application uses a non-venting regulator, refer
to A Note Concerning Non-Venting Regulators in Closed Loop
Applications if you intend to use the ER5000 in this condition.
CAUTION
The Control Limits feature provides an additional level of system
monitoring. Activation indicates a potential problem, but will not, by
itself, prevent problems from occurring. It should not be considered
to be a safety mechanism, nor is it intended to be a safety feature or
pressure limiting device.
The entry fields in this panel allow you to monitor any or all of five
ER5000 internal variables and to set minimum and/or maximum
limits to be tracked for each source. If multiple variables are
selected the ER5000 will respond when any of the assigned sources
exceeds the set limit.
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