Knick Protos 3400, User Manual

Page: 59 / 212

59
NAMUR Signals: Relay Contacts
Failure, maintenance request, HOLD (function check)
Failure is active
when a value has exceeded (or fallen below, resp.) a preset ”Failure Limit Hi”
or ”Failure Limit Lo”, when the measured value is out of range, or in the event
of other failure messages. That means that the equipment no longer operates
properly or that process parameters have reached a critical value.
Failure is disabled during "HOLD" (Function check).
Maintenance request is active
when a value has exceeded (or fallen below, resp.) a preset "Warning Limit Hi"
or "Warning Limit Lo", or when other warning messages have been activated.
That means that the equipment is still operating properly but should be ser-
viced, or that process parameters have reached a value requiring intervention.
Warning is disabled during "HOLD" (function check).
HOLD is active:
• during calibration
• during maintenance (current source, meas. point maintenance)
• during parameter setting at the Operator level and the Administrator level
• during an automatic rinsing cycle
As delivered, the floating relay outputs of the BASE module are assigned to the
NAMUR signals:
Failure
Contact K4, normally closed
(signaling current failure)
Maintenance request Contact K3, normally open contact
HOLD Contact K2, normally open contact
NAMUR signals: Factory setting of contacts
• Select parameter setting
• Administrator level
• Select “Module BASE” (Fig.)
You can define a delay time for “Maintenance request”
and “Failure”, resp.
If an alarm message is released, the contact will only be
activated after expiry of this delay time.
Module BASE (Administrator)
Output current I1
Return Block
7.00 pH
Contact K4
Output current I2
Contact K3
19.0°C
(NAMUR failure)
Contact K2
Contact K1
(NAMUR maintenance)
(NAMUR HOLD)
(Limit)