YSI IQ SensorNet 2020 XT Terminal - Manual (Page 24)

Overview System 2020 XT USB
1 - 18 ba76019e01 12/2012
1.4 Behavior of the IQ S ENSOR N ET in case of error
1.4.1 Behavior of the IQ S ENSOR N ET in case of power failure
 The system configuration (Settings of sensors and diff. sensors and
Settings of outputs and links) is stored permanently
 All stored measured data remain permanently available
 Linked current outputs and relay outputs switch to the non-active
condition.
Current output: 0 mA current
Relay output: Relays open
For details, refer to the component operating manual of the current
or relay output module.
 When the power supply is available again, the system is
automatically restarted, starts working again and switches to the
measured value display
 During the restart, an entry informing of the power failure is made in
the log book.
1.4.2 Behavior of the IQ S ENSOR N ET if a components fails
 If the operating voltage is too low, the LEDs on the MIQ modules
extinguish.
 The blue status LED of the MIQ/TC 2020 XT flashes
 If active components (e.g. sensors or output modules) cannot be
contacted, an entry is made in the log book. The error symbol
flashes on the display.
 The Edit list of sensors or Edit list of outputs display shows a
question mark "?" for the component.
Component Behavior
IQ sensor  The configuration for the IQ sensor (Settings of
sensors and diff. sensors) remains stored.
 Current measured values are not available.
 The measured value display shows ERROR.
MIQ modules  If an active module fails, an entry is made in the
log book. The error symbol flashes on the
display.
 The configuration for these modules is retained
(e.g. links with output modules).