Siemens Pointek CLS200 Operating Instructions Manual page 76

Fault Signaling
The Failsafe function puts the process into a safe mode of operation in the event of a fault
or failure (such as a loss of power). When the Pointek CLS200/300 standard model
responds to a failure, the output switches according to the Failsafe setting
two Failsafe options:
• Failsafe High
• Failsafe Low
The following examples assume that the pump should be turned off in the event
Note:
of a failure. If this is not the case in your process, please see the relay diagram on
page 25, and make the appropriate connections to suit your application.
Failsafe High is used in applications where Pointek CLS200/300 is set to turn off a pump
when the level becomes too high (probe covered, or level too close to probe). When
Failsafe High is selected, the device will respond to a failure (regardless of the true level)
as if it were a high level alarm (alarm ON/solid-state switch open). The pump will stop,
preventing an overfill.
Failsafe Low is used in applications where CLS200/300 is set to turn off a pump when the
level becomes too low (probe uncovered). When Failsafe Low is selected, CLS200/300 will
respond to a failure (regardless of the true level) as if it were a low level (alarm ON/solid-
state switch open). The pump will stop, preventing the pump from running dry.
no fault
uncovered covered uncovered covered uncovered covered uncovered covered
probe
CLOSED
switch
OFF
alarm
1.
Failsafe/Alarm Setting: S3
See
7ML19985JH01 Pointek CLS200/300 Standard – INSTRUCTION MANUAL
Failsafe High
fault
OPEN OPEN
ON ON
on page 26 for details.
Failsafe Low
no fault
OPEN CLOSED
ON OFF
1
. There are
fault
OPEN
ON
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